diff --git a/Makefile b/Makefile
index 08a0fda0..5680ce57 100644
--- a/Makefile
+++ b/Makefile
@@ -15,61 +15,20 @@
 #   limitations under the License.
 # ****************************************************************************
 
-ifeq ($(BOLOS_SDK),)
-$(error Environment variable BOLOS_SDK is not set)
-endif
-include $(BOLOS_SDK)/Makefile.defines
-
 ########################################
 #        Mandatory configuration       #
 ########################################
-# Name is defined later
 
 # Application version
 APPVERSION_M = 2
 APPVERSION_N = 3
 APPVERSION_P = 0
-APPVERSION = "$(APPVERSION_M).$(APPVERSION_N).$(APPVERSION_P)"
-
-# Application source files
-APP_SOURCE_PATH += src
-
-ICON_NANOS = icons/nanos_app_$(COIN).gif
-ICON_NANOX = icons/nanox_app_$(COIN).gif
-ICON_NANOSP = icons/nanox_app_$(COIN).gif
-ICON_STAX = icons/stax_app_$(COIN).gif
-
-# Application allowed derivation curves.
-CURVE_APP_LOAD_PARAMS = secp256k1
 
-# Application allowed derivation paths.
-ifeq ($(COIN),$(filter $(COIN), hydra_testnet hydra))
-PATH_APP_LOAD_PARAMS = "44'/609'"
-else
-PATH_APP_LOAD_PARAMS = ""
-endif
-
-HAVE_APPLICATION_FLAG_DERIVE_MASTER = 1
-HAVE_APPLICATION_FLAG_LIBRARY = 1
-
-VARIANT_PARAM = COIN
-VARIANT_VALUES = BOL
-
-# Temporary restriction until we have a Resistance Nano X icon
-ifeq ($(TARGET_NAME),TARGET_NANOS)
-VARIANT_VALUES = bitcoin_testnet_legacy bitcoin_legacy bitcoin_cash bitcoin_gold litecoin dogecoin dash horizen komodo stratis peercoin pivx viacoin vertcoin stealth digibyte bitcoin_private firo gamecredits zclassic xsn nix lbry ravencoin resistance hydra hydra_testnet xrhodium
-else
 VARIANT_VALUES = bitcoin_testnet_legacy bitcoin_legacy bitcoin_cash bitcoin_gold litecoin dogecoin dash horizen komodo stratis peercoin pivx viacoin vertcoin stealth digibyte bitcoin_private firo gamecredits zclassic xsn nix lbry ravencoin hydra hydra_testnet xrhodium
-endif
-
-ENABLE_BLUETOOTH = 1
-ENABLE_NBGL_QRCODE = 1
-ENABLE_SWAP = 1
 
-ifeq ($(TARGET_NAME),TARGET_STAX)
-DEFINES += COIN_ICON=C_$(COIN)_64px
-DEFINES += COIN_ICON_BITMAP=C_$(COIN)_64px_bitmap
-endif
+# Application source files
+# There is no additional sources for bitcoin
+#APP_SOURCE_PATH += src/
 
 # simplify for tests
 ifndef COIN
@@ -80,135 +39,450 @@ endif
 #DEBUG = 1
 
 ifeq ($(COIN),bitcoin_testnet_legacy)
-# Bitcoin testnet
-DEFINES   += BIP44_COIN_TYPE=1 BIP44_COIN_TYPE_2=1 COIN_P2PKH_VERSION=111 COIN_P2SH_VERSION=196 COIN_FAMILY=1 COIN_COINID=\"Bitcoin\" COIN_COINID_HEADER=\"BITCOIN\" COIN_COINID_NAME=\"Bitcoin\" COIN_COINID_SHORT=\"TEST\" COIN_NATIVE_SEGWIT_PREFIX=\"tb\" COIN_KIND=COIN_KIND_BITCOIN_TESTNET COIN_FLAGS=FLAG_SEGWIT_CHANGE_SUPPORT
+BIP44_COIN_TYPE=1
+BIP44_COIN_TYPE_2=1
+COIN_P2PKH_VERSION=111
+COIN_P2SH_VERSION=196
+COIN_FAMILY=1
+COIN_COINID=\"Bitcoin\"
+COIN_COINID_HEADER=\"BITCOIN\" 
+COIN_COINID_NAME=\"Bitcoin\" 
+COIN_COINID_SHORT=\"TEST\" 
+COIN_NATIVE_SEGWIT_PREFIX=\"tb\" 
+COIN_KIND=COIN_KIND_BITCOIN_TESTNET 
+COIN_FLAGS=FLAG_SEGWIT_CHANGE_SUPPORT
 APPNAME ="Bitcoin Test Legacy"
+
 else ifeq ($(COIN),bitcoin_legacy)
-# Bitcoin mainnet
-DEFINES   += BIP44_COIN_TYPE=0 BIP44_COIN_TYPE_2=0 COIN_P2PKH_VERSION=0 COIN_P2SH_VERSION=5 COIN_FAMILY=1 COIN_COINID=\"Bitcoin\" COIN_COINID_HEADER=\"BITCOIN\" COIN_COINID_NAME=\"Bitcoin\" COIN_COINID_SHORT=\"BTC\" COIN_NATIVE_SEGWIT_PREFIX=\"bc\" COIN_KIND=COIN_KIND_BITCOIN COIN_FLAGS=FLAG_SEGWIT_CHANGE_SUPPORT
+# Horizen
+BIP44_COIN_TYPE=0 
+BIP44_COIN_TYPE_2=0 
+COIN_P2PKH_VERSION=0 
+COIN_P2SH_VERSION=5 
+COIN_FAMILY=1 
+COIN_COINID=\"Bitcoin\" 
+COIN_COINID_HEADER=\"BITCOIN\" 
+COIN_COINID_NAME=\"Bitcoin\" 
+COIN_COINID_SHORT=\"BTC\" 
+COIN_NATIVE_SEGWIT_PREFIX=\"bc\" 
+COIN_KIND=COIN_KIND_BITCOIN 
+COIN_FLAGS=FLAG_SEGWIT_CHANGE_SUPPORT
 APPNAME ="Bitcoin Legacy"
-#LIB and global pin and
+
 else ifeq ($(COIN),bitcoin_cash)
 # Bitcoin cash
 # Initial fork from Bitcoin, public key access is authorized. Signature is different thanks to the forkId
-DEFINES   += BIP44_COIN_TYPE=145 BIP44_COIN_TYPE_2=0 COIN_P2PKH_VERSION=0 COIN_P2SH_VERSION=5 COIN_FAMILY=1 COIN_COINID=\"Bitcoin\" COIN_COINID_HEADER=\"BITCOINCASH\" COIN_COINID_NAME=\"BitcoinCash\" COIN_COINID_SHORT=\"BCH\" COIN_KIND=COIN_KIND_BITCOIN_CASH COIN_FORKID=0
+BIP44_COIN_TYPE=145 
+BIP44_COIN_TYPE_2=0 
+COIN_P2PKH_VERSION=0 
+COIN_P2SH_VERSION=5 
+COIN_FAMILY=1 
+COIN_COINID=\"Bitcoin\" 
+COIN_COINID_HEADER=\"BITCOINCASH\" 
+COIN_COINID_NAME=\"BitcoinCash\" 
+COIN_COINID_SHORT=\"BCH\" 
+COIN_KIND=COIN_KIND_BITCOIN_CASH 
+COIN_FORKID=0
 APPNAME ="Bitcoin Cash"
+
 else ifeq ($(COIN),bitcoin_gold)
 # Bitcoin Gold
 # Initial fork from Bitcoin, public key access is authorized. Signature is different thanks to the forkId
-DEFINES   += BIP44_COIN_TYPE=156 BIP44_COIN_TYPE_2=0 COIN_P2PKH_VERSION=38 COIN_P2SH_VERSION=23 COIN_FAMILY=1 COIN_COINID=\"Bitcoin\\x20Gold\" COIN_COINID_HEADER=\"BITCOINGOLD\" COIN_COINID_NAME=\"BitcoinGold\" COIN_COINID_SHORT=\"BTG\" COIN_KIND=COIN_KIND_BITCOIN_GOLD COIN_FLAGS=FLAG_SEGWIT_CHANGE_SUPPORT COIN_FORKID=79
+BIP44_COIN_TYPE=156 
+BIP44_COIN_TYPE_2=0 
+COIN_P2PKH_VERSION=38 
+COIN_P2SH_VERSION=23 
+COIN_FAMILY=1 
+COIN_COINID=\"Bitcoin\\x20Gold\" 
+COIN_COINID_HEADER=\"BITCOINGOLD\" 
+COIN_COINID_NAME=\"BitcoinGold\" 
+COIN_COINID_SHORT=\"BTG\" 
+COIN_KIND=COIN_KIND_BITCOIN_GOLD 
+COIN_FLAGS=FLAG_SEGWIT_CHANGE_SUPPORT 
+COIN_FORKID=79
 APPNAME ="Bitcoin Gold"
+
 else ifeq ($(COIN),litecoin)
 # Litecoin
-DEFINES   += BIP44_COIN_TYPE=2 BIP44_COIN_TYPE_2=2 COIN_P2PKH_VERSION=48 COIN_P2SH_VERSION=50 COIN_FAMILY=1 COIN_COINID=\"Litecoin\" COIN_COINID_HEADER=\"LITECOIN\" COIN_COINID_NAME=\"Litecoin\" COIN_COINID_SHORT=\"LTC\" COIN_NATIVE_SEGWIT_PREFIX=\"ltc\" COIN_KIND=COIN_KIND_LITECOIN COIN_FLAGS=FLAG_SEGWIT_CHANGE_SUPPORT
+BIP44_COIN_TYPE=2 
+BIP44_COIN_TYPE_2=2 
+COIN_P2PKH_VERSION=48 
+COIN_P2SH_VERSION=50 
+COIN_FAMILY=1 
+COIN_COINID=\"Litecoin\" 
+COIN_COINID_HEADER=\"LITECOIN\" 
+COIN_COINID_NAME=\"Litecoin\" 
+COIN_COINID_SHORT=\"LTC\" 
+COIN_NATIVE_SEGWIT_PREFIX=\"ltc\" 
+COIN_KIND=COIN_KIND_LITECOIN 
+COIN_FLAGS=FLAG_SEGWIT_CHANGE_SUPPORT
 APPNAME ="Litecoin"
+
 else ifeq ($(COIN),dogecoin)
 # Doge
-DEFINES   += BIP44_COIN_TYPE=3 BIP44_COIN_TYPE_2=3 COIN_P2PKH_VERSION=30 COIN_P2SH_VERSION=22 COIN_FAMILY=1 COIN_COINID=\"Dogecoin\" COIN_COINID_HEADER=\"DOGECOIN\" COIN_COINID_NAME=\"Dogecoin\" COIN_COINID_SHORT=\"DOGE\" COIN_KIND=COIN_KIND_DOGE
+BIP44_COIN_TYPE=3 
+BIP44_COIN_TYPE_2=3 
+COIN_P2PKH_VERSION=30 
+COIN_P2SH_VERSION=22 
+COIN_FAMILY=1 
+COIN_COINID=\"Dogecoin\" 
+COIN_COINID_HEADER=\"DOGECOIN\" 
+COIN_COINID_NAME=\"Dogecoin\" 
+COIN_COINID_SHORT=\"DOGE\" 
+COIN_KIND=COIN_KIND_DOGE
 APPNAME ="Dogecoin"
+
 else ifeq ($(COIN),dash)
 # Dash
-DEFINES   += BIP44_COIN_TYPE=5 BIP44_COIN_TYPE_2=5 COIN_P2PKH_VERSION=76 COIN_P2SH_VERSION=16 COIN_FAMILY=1 COIN_COINID=\"DarkCoin\" COIN_COINID_HEADER=\"DASH\" COIN_COINID_NAME=\"Dash\" COIN_COINID_SHORT=\"DASH\" COIN_KIND=COIN_KIND_DASH
+BIP44_COIN_TYPE=5 
+BIP44_COIN_TYPE_2=5 
+COIN_P2PKH_VERSION=76 
+COIN_P2SH_VERSION=16 
+COIN_FAMILY=1 
+COIN_COINID=\"DarkCoin\" 
+COIN_COINID_HEADER=\"DASH\" 
+COIN_COINID_NAME=\"Dash\" 
+COIN_COINID_SHORT=\"DASH\" 
+COIN_KIND=COIN_KIND_DASH
 APPNAME ="Dash"
+
 else ifeq ($(COIN),zcash)
 # Zcash (deprecated, code before the NU5 hard fork)
 $(error the zcash variant is deprecated and no longer functional since the NU5 hard fork)
-DEFINES   += BIP44_COIN_TYPE=133 BIP44_COIN_TYPE_2=133 COIN_P2PKH_VERSION=7352 COIN_P2SH_VERSION=7357 COIN_FAMILY=1 COIN_COINID=\"Zcash\" COIN_COINID_HEADER=\"ZCASH\" COIN_COINID_NAME=\"Zcash\" COIN_COINID_SHORT=\"ZEC\" COIN_KIND=COIN_KIND_ZCASH
+BIP44_COIN_TYPE=133 
+BIP44_COIN_TYPE_2=133 
+COIN_P2PKH_VERSION=7352 
+COIN_P2SH_VERSION=7357 
+COIN_FAMILY=1 
+COIN_COINID=\"Zcash\" 
+COIN_COINID_HEADER=\"ZCASH\" 
+COIN_COINID_NAME=\"Zcash\" 
+COIN_COINID_SHORT=\"ZEC\" 
+COIN_KIND=COIN_KIND_ZCASH
 # Switch to Canopy over Heartwood
-DEFINES   += COIN_CONSENSUS_BRANCH_ID=0xE9FF75A6
+BRANCH_ID=0xE9FF75A6
 APPNAME ="Zcash"
+
 else ifeq ($(COIN),horizen)
 # Horizen
-DEFINES   += BIP44_COIN_TYPE=121 BIP44_COIN_TYPE_2=121 COIN_P2PKH_VERSION=8329 COIN_P2SH_VERSION=8342 COIN_FAMILY=4 COIN_COINID=\"Horizen\" COIN_COINID_HEADER=\"HORIZEN\" COIN_COINID_NAME=\"Horizen\" COINID=$(COIN) COIN_COINID_SHORT=\"ZEN\" COIN_KIND=COIN_KIND_HORIZEN
+BIP44_COIN_TYPE=121 
+BIP44_COIN_TYPE_2=121 
+COIN_P2PKH_VERSION=8329 
+COIN_P2SH_VERSION=8342 
+COIN_FAMILY=4 
+COIN_COINID=\"Horizen\" 
+COIN_COINID_HEADER=\"HORIZEN\" 
+COIN_COINID_NAME=\"Horizen\" 
+COIN_COINID_SHORT=\"ZEN\" 
+COIN_KIND=COIN_KIND_HORIZEN
 APPNAME ="Horizen"
+
 else ifeq ($(COIN),komodo)
 # Komodo
-DEFINES   += BIP44_COIN_TYPE=141 BIP44_COIN_TYPE_2=141 COIN_P2PKH_VERSION=60 COIN_P2SH_VERSION=85 COIN_FAMILY=1 COIN_COINID=\"Komodo\" COIN_COINID_HEADER=\"KOMODO\" COIN_COINID_NAME=\"Komodo\" COIN_COINID_SHORT=\"KMD\" COIN_KIND=COIN_KIND_KOMODO
+BIP44_COIN_TYPE=141 
+BIP44_COIN_TYPE_2=141 
+COIN_P2PKH_VERSION=60 
+COIN_P2SH_VERSION=85 
+COIN_FAMILY=1 
+COIN_COINID=\"Komodo\" 
+COIN_COINID_HEADER=\"KOMODO\" 
+COIN_COINID_NAME=\"Komodo\" 
+COIN_COINID_SHORT=\"KMD\" 
+COIN_KIND=COIN_KIND_KOMODO
 APPNAME ="Komodo"
+
 else ifeq ($(COIN),stratis)
 # Stratis
-DEFINES   += BIP44_COIN_TYPE=105105 BIP44_COIN_TYPE_2=105105 COIN_P2PKH_VERSION=75 COIN_P2SH_VERSION=140 COIN_FAMILY=2 COIN_COINID=\"Stratis\" COIN_COINID_HEADER=\"STRATIS\" COIN_COINID_NAME=\"Stratis\" COIN_COINID_SHORT=\"STRAX\" COIN_KIND=COIN_KIND_STRATIS COIN_FLAGS=FLAG_PEERCOIN_SUPPORT
+BIP44_COIN_TYPE=105105 
+BIP44_COIN_TYPE_2=105105 
+COIN_P2PKH_VERSION=75 
+COIN_P2SH_VERSION=140 
+COIN_FAMILY=2 
+COIN_COINID=\"Stratis\" 
+COIN_COINID_HEADER=\"STRATIS\" 
+COIN_COINID_NAME=\"Stratis\" 
+COIN_COINID_SHORT=\"STRAX\" 
+COIN_KIND=COIN_KIND_STRATIS 
+COIN_FLAGS=FLAG_PEERCOIN_SUPPORT
 APPNAME ="Stratis"
+
 else ifeq ($(COIN),xrhodium)
 #Xrhodium
-DEFINES   += BIP44_COIN_TYPE=10291 BIP44_COIN_TYPE_2=10291 COIN_P2PKH_VERSION=61 COIN_P2SH_VERSION=123 COIN_FAMILY=1 COIN_COINID=\"xrhodium\" COIN_COINID_HEADER=\"XRHODIUM\" COIN_COINID_NAME=\"xRhodium\" COIN_COINID_SHORT=\"XRC\" COIN_KIND=COIN_KIND_XRHODIUM
+BIP44_COIN_TYPE=10291 
+BIP44_COIN_TYPE_2=10291 
+COIN_P2PKH_VERSION=61 
+COIN_P2SH_VERSION=123 
+COIN_FAMILY=1 
+COIN_COINID=\"xrhodium\" 
+COIN_COINID_HEADER=\"XRHODIUM\" 
+COIN_COINID_NAME=\"xRhodium\" 
+COIN_COINID_SHORT=\"XRC\" 
+COIN_KIND=COIN_KIND_XRHODIUM
 APPNAME ="xRhodium"
+
 else ifeq ($(COIN),peercoin)
 # Peercoin
-DEFINES += BIP44_COIN_TYPE=6 BIP44_COIN_TYPE_2=6 COIN_P2PKH_VERSION=55 COIN_P2SH_VERSION=117 COIN_FAMILY=2 COIN_COINID=\"PPCoin\" COIN_COINID_HEADER=\"PEERCOIN\" COIN_COINID_NAME=\"Peercoin\" COIN_COINID_SHORT=\"PPC\" COIN_KIND=COIN_KIND_PEERCOIN COIN_FLAGS=FLAG_PEERCOIN_UNITS\|FLAG_PEERCOIN_SUPPORT
+BIP44_COIN_TYPE=6 
+BIP44_COIN_TYPE_2=6 
+COIN_P2PKH_VERSION=55 
+COIN_P2SH_VERSION=117 
+COIN_FAMILY=2 
+COIN_COINID=\"PPCoin\" 
+COIN_COINID_HEADER=\"PEERCOIN\" 
+COIN_COINID_NAME=\"Peercoin\" 
+COIN_COINID_SHORT=\"PPC\" 
+COIN_KIND=COIN_KIND_PEERCOIN 
+COIN_FLAGS=FLAG_PEERCOIN_UNITS\|FLAG_PEERCOIN_SUPPORT
 APPNAME ="Peercoin"
+
 else ifeq ($(COIN),pivx)
 # PivX
 # 77 was used in the Chrome apps
-DEFINES   += BIP44_COIN_TYPE=119 BIP44_COIN_TYPE_2=77 COIN_P2PKH_VERSION=30 COIN_P2SH_VERSION=13 COIN_FAMILY=1 COIN_COINID=\"DarkNet\" COIN_COINID_HEADER=\"PIVX\" COIN_COINID_NAME=\"PivX\" COIN_COINID_SHORT=\"PIVX\" COIN_KIND=COIN_KIND_PIVX
+BIP44_COIN_TYPE=119 
+BIP44_COIN_TYPE_2=77 
+COIN_P2PKH_VERSION=30 
+COIN_P2SH_VERSION=13 
+COIN_FAMILY=1 
+COIN_COINID=\"DarkNet\" 
+COIN_COINID_HEADER=\"PIVX\" 
+COIN_COINID_NAME=\"PivX\" 
+COIN_COINID_SHORT=\"PIVX\" 
+COIN_KIND=COIN_KIND_PIVX
 APPNAME ="PivX"
+
 else ifeq ($(COIN),stealth)
 # Stealth
-DEFINES   += BIP44_COIN_TYPE=125 BIP44_COIN_TYPE_2=125 COIN_P2PKH_VERSION=62 COIN_P2SH_VERSION=85 COIN_FAMILY=4 COIN_COINID=\"Stealth\" COIN_COINID_HEADER=\"STEALTH\" COIN_COINID_NAME=\"Stealth\" COIN_COINID_SHORT=\"XST\" COIN_KIND=COIN_KIND_STEALTH COIN_FLAGS=FLAG_PEERCOIN_UNITS\|FLAG_PEERCOIN_SUPPORT
+BIP44_COIN_TYPE=125 
+BIP44_COIN_TYPE_2=125 
+COIN_P2PKH_VERSION=62 
+COIN_P2SH_VERSION=85 
+COIN_FAMILY=4 
+COIN_COINID=\"Stealth\" 
+COIN_COINID_HEADER=\"STEALTH\" 
+COIN_COINID_NAME=\"Stealth\" 
+COIN_COINID_SHORT=\"XST\" 
+COIN_KIND=COIN_KIND_STEALTH 
+COIN_FLAGS=FLAG_PEERCOIN_UNITS\|FLAG_PEERCOIN_SUPPORT
 APPNAME ="Stealth"
+
 else ifeq ($(COIN),viacoin)
 # Viacoin
-DEFINES   += BIP44_COIN_TYPE=14 BIP44_COIN_TYPE_2=14 COIN_P2PKH_VERSION=71 COIN_P2SH_VERSION=33 COIN_FAMILY=1 COIN_COINID=\"Viacoin\" COIN_COINID_HEADER=\"VIACOIN\" COIN_COINID_NAME=\"Viacoin\" COIN_COINID_SHORT=\"VIA\" COIN_KIND=COIN_KIND_VIACOIN COIN_FLAGS=FLAG_SEGWIT_CHANGE_SUPPORT
+BIP44_COIN_TYPE=14 
+BIP44_COIN_TYPE_2=14 
+COIN_P2PKH_VERSION=71 
+COIN_P2SH_VERSION=33 
+COIN_FAMILY=1 
+COIN_COINID=\"Viacoin\" 
+COIN_COINID_HEADER=\"VIACOIN\" 
+COIN_COINID_NAME=\"Viacoin\" 
+COIN_COINID_SHORT=\"VIA\" 
+COIN_KIND=COIN_KIND_VIACOIN 
+COIN_FLAGS=FLAG_SEGWIT_CHANGE_SUPPORT
 APPNAME ="Viacoin"
+
 else ifeq ($(COIN),vertcoin)
 # Vertcoin
 # 128 was used in the Chrome apps
-DEFINES   += BIP44_COIN_TYPE=28 BIP44_COIN_TYPE_2=128 COIN_P2PKH_VERSION=71 COIN_P2SH_VERSION=5 COIN_FAMILY=1 COIN_COINID=\"Vertcoin\" COIN_COINID_HEADER=\"VERTCOIN\" COIN_COINID_NAME=\"Vertcoin\" COIN_COINID_SHORT=\"VTC\" COIN_NATIVE_SEGWIT_PREFIX=\"vtc\" COIN_KIND=COIN_KIND_VERTCOIN COIN_FLAGS=FLAG_SEGWIT_CHANGE_SUPPORT
+BIP44_COIN_TYPE=28 
+BIP44_COIN_TYPE_2=128 
+COIN_P2PKH_VERSION=71 
+COIN_P2SH_VERSION=5 
+COIN_FAMILY=1 
+COIN_COINID=\"Vertcoin\" 
+COIN_COINID_HEADER=\"VERTCOIN\" 
+COIN_COINID_NAME=\"Vertcoin\" 
+COIN_COINID_SHORT=\"VTC\" 
+COIN_NATIVE_SEGWIT_PREFIX=\"vtc\" 
+COIN_KIND=COIN_KIND_VERTCOIN 
+COIN_FLAGS=FLAG_SEGWIT_CHANGE_SUPPORT
 APPNAME ="Vertcoin"
+
 else ifeq ($(COIN),digibyte)
-DEFINES   += BIP44_COIN_TYPE=20 BIP44_COIN_TYPE_2=20 COIN_P2PKH_VERSION=30 COIN_P2SH_VERSION=63 COIN_FAMILY=1 COIN_COINID=\"DigiByte\" COIN_COINID_HEADER=\"DIGIBYTE\" COIN_COINID_NAME=\"DigiByte\" COIN_COINID_SHORT=\"DGB\" COIN_NATIVE_SEGWIT_PREFIX=\"dgb\" COIN_KIND=COIN_KIND_DIGIBYTE COIN_FLAGS=FLAG_SEGWIT_CHANGE_SUPPORT
+BIP44_COIN_TYPE=20 
+BIP44_COIN_TYPE_2=20 
+COIN_P2PKH_VERSION=30 
+COIN_P2SH_VERSION=63 
+COIN_FAMILY=1 
+COIN_COINID=\"DigiByte\" 
+COIN_COINID_HEADER=\"DIGIBYTE\" 
+COIN_COINID_NAME=\"DigiByte\" 
+COIN_COINID_SHORT=\"DGB\" 
+COIN_NATIVE_SEGWIT_PREFIX=\"dgb\" 
+COIN_KIND=COIN_KIND_DIGIBYTE 
+COIN_FLAGS=FLAG_SEGWIT_CHANGE_SUPPORT
 APPNAME ="Digibyte"
+
 else ifeq ($(COIN),qtum)
 $(error the qtum variant is deprecated and has been moved to its dedicated repo
 else ifeq ($(COIN),firo)
-DEFINES   += BIP44_COIN_TYPE=136 BIP44_COIN_TYPE_2=136 COIN_P2PKH_VERSION=82 COIN_P2SH_VERSION=7 COIN_FAMILY=1 COIN_COINID=\"Zcoin\" COIN_COINID_HEADER=\"FIRO\" COIN_COINID_NAME=\"Firo\" COIN_COINID_SHORT=\"FIRO\" COIN_KIND=COIN_KIND_FIRO
+BIP44_COIN_TYPE=136 
+BIP44_COIN_TYPE_2=136 
+COIN_P2PKH_VERSION=82 
+COIN_P2SH_VERSION=7 
+COIN_FAMILY=1 
+COIN_COINID=\"Zcoin\" 
+COIN_COINID_HEADER=\"FIRO\" 
+COIN_COINID_NAME=\"Firo\" 
+COIN_COINID_SHORT=\"FIRO\" 
+COIN_KIND=COIN_KIND_FIRO
 APPNAME ="Firo"
+
 else ifeq ($(COIN),bitcoin_private)
 # Bitcoin Private
 # Initial fork from Bitcoin, public key access is authorized. Signature is different thanks to the forkId
 # Note : might need a third lock on ZClassic
-DEFINES   += BIP44_COIN_TYPE=183 BIP44_COIN_TYPE_2=0 COIN_P2PKH_VERSION=4901 COIN_P2SH_VERSION=5039 COIN_FAMILY=1 COIN_COINID=\"BPrivate\" COIN_COINID_HEADER=\"BITCOINPRIVATE\" COIN_COINID_NAME=\"BPrivate\" COIN_COINID_SHORT=\"BTCP\" COIN_KIND=COIN_KIND_BITCOIN_PRIVATE COIN_FORKID=42
+BIP44_COIN_TYPE=183 
+BIP44_COIN_TYPE_2=0 
+COIN_P2PKH_VERSION=4901 
+COIN_P2SH_VERSION=5039 
+COIN_FAMILY=1 
+COIN_COINID=\"BPrivate\" 
+COIN_COINID_HEADER=\"BITCOINPRIVATE\" 
+COIN_COINID_NAME=\"BPrivate\" 
+COIN_COINID_SHORT=\"BTCP\" 
+COIN_KIND=COIN_KIND_BITCOIN_PRIVATE 
+COIN_FORKID=42
 APPNAME ="Bitcoin Private"
+
 else ifeq ($(COIN),gamecredits)
 # GameCredits
-DEFINES   += BIP44_COIN_TYPE=101  BIP44_COIN_TYPE_2=101 COIN_P2PKH_VERSION=38 COIN_P2SH_VERSION=62 COIN_FAMILY=1 COIN_COINID=\"GameCredits\" COIN_COINID_HEADER=\"GAMECREDITS\" COIN_COINID_NAME=\"GameCredits\" COIN_COINID_SHORT=\"GAME\" COIN_KIND=COIN_KIND_GAMECREDITS COIN_FLAGS=FLAG_SEGWIT_CHANGE_SUPPORT
+BIP44_COIN_TYPE=101  
+BIP44_COIN_TYPE_2=101 
+COIN_P2PKH_VERSION=38 
+COIN_P2SH_VERSION=62 
+COIN_FAMILY=1 
+COIN_COINID=\"GameCredits\" 
+COIN_COINID_HEADER=\"GAMECREDITS\" 
+COIN_COINID_NAME=\"GameCredits\" 
+COIN_COINID_SHORT=\"GAME\" 
+COIN_KIND=COIN_KIND_GAMECREDITS 
+COIN_FLAGS=FLAG_SEGWIT_CHANGE_SUPPORT
 APPNAME ="GameCredits"
+
 else ifeq ($(COIN),zclassic)
 # ZClassic
-DEFINES   += BIP44_COIN_TYPE=147  BIP44_COIN_TYPE_2=147 COIN_P2PKH_VERSION=7352 COIN_P2SH_VERSION=7357 COIN_FAMILY=1 COIN_COINID=\"ZClassic\" COIN_COINID_HEADER=\"ZCLASSIC\" COIN_COINID_NAME=\"ZClassic\" COIN_COINID_SHORT=\"ZCL\" COIN_KIND=COIN_KIND_ZCLASSIC
+BIP44_COIN_TYPE=147  
+BIP44_COIN_TYPE_2=147 
+COIN_P2PKH_VERSION=7352 
+COIN_P2SH_VERSION=7357 
+COIN_FAMILY=1 
+COIN_COINID=\"ZClassic\" 
+COIN_COINID_HEADER=\"ZCLASSIC\" 
+COIN_COINID_NAME=\"ZClassic\" 
+COIN_COINID_SHORT=\"ZCL\" 
+COIN_KIND=COIN_KIND_ZCLASSIC
 APPNAME ="ZClassic"
+
 else ifeq ($(COIN),xsn)
 # XSN mainnet
-DEFINES   += BIP44_COIN_TYPE=384  BIP44_COIN_TYPE_2=384 COIN_P2PKH_VERSION=76 COIN_P2SH_VERSION=16 COIN_FAMILY=1 COIN_COINID=\"XSN\" COIN_COINID_HEADER=\"XSN\" COIN_COINID_NAME=\"XSN\" COIN_COINID_SHORT=\"XSN\" COIN_NATIVE_SEGWIT_PREFIX=\"xc\" COIN_KIND=COIN_KIND_XSN COIN_FLAGS=FLAG_SEGWIT_CHANGE_SUPPORT
+BIP44_COIN_TYPE=384  
+BIP44_COIN_TYPE_2=384 
+COIN_P2PKH_VERSION=76 
+COIN_P2SH_VERSION=16 
+COIN_FAMILY=1 
+COIN_COINID=\"XSN\" 
+COIN_COINID_HEADER=\"XSN\" 
+COIN_COINID_NAME=\"XSN\" 
+COIN_COINID_SHORT=\"XSN\" 
+COIN_NATIVE_SEGWIT_PREFIX=\"xc\" 
+COIN_KIND=COIN_KIND_XSN 
+COIN_FLAGS=FLAG_SEGWIT_CHANGE_SUPPORT
 APPNAME ="XSN"
+
 else ifeq ($(COIN),nix)
 # NIX
-DEFINES   += BIP44_COIN_TYPE=400  BIP44_COIN_TYPE_2=400 COIN_P2PKH_VERSION=38 COIN_P2SH_VERSION=53 COIN_FAMILY=1 COIN_COINID=\"NIX\" COIN_COINID_HEADER=\"NIX\" COIN_COINID_NAME=\"NIX\" COIN_COINID_SHORT=\"NIX\" COIN_NATIVE_SEGWIT_PREFIX=\"nix\" COIN_KIND=COIN_KIND_NIX COIN_FLAGS=FLAG_SEGWIT_CHANGE_SUPPORT
+BIP44_COIN_TYPE=400  
+BIP44_COIN_TYPE_2=400 
+COIN_P2PKH_VERSION=38 
+COIN_P2SH_VERSION=53 
+COIN_FAMILY=1 
+COIN_COINID=\"NIX\" 
+COIN_COINID_HEADER=\"NIX\" 
+COIN_COINID_NAME=\"NIX\" 
+COIN_COINID_SHORT=\"NIX\" 
+COIN_NATIVE_SEGWIT_PREFIX=\"nix\" 
+COIN_KIND=COIN_KIND_NIX 
+COIN_FLAGS=FLAG_SEGWIT_CHANGE_SUPPORT
 APPNAME ="NIX"
+
 else ifeq ($(COIN),lbry)
 # LBRY
-DEFINES   += BIP44_COIN_TYPE=140  BIP44_COIN_TYPE_2=140 COIN_P2PKH_VERSION=85 COIN_P2SH_VERSION=122 COIN_FAMILY=1 COIN_COINID=\"LBRY\" COIN_COINID_HEADER=\"LBRY\" COIN_COINID_NAME=\"LBRY\" COIN_COINID_SHORT=\"LBC\" COIN_KIND=COIN_KIND_LBRY
+BIP44_COIN_TYPE=140  
+BIP44_COIN_TYPE_2=140 
+COIN_P2PKH_VERSION=85 
+COIN_P2SH_VERSION=122 
+COIN_FAMILY=1 
+COIN_COINID=\"LBRY\" 
+COIN_COINID_HEADER=\"LBRY\" 
+COIN_COINID_NAME=\"LBRY\" 
+COIN_COINID_SHORT=\"LBC\" 
+COIN_KIND=COIN_KIND_LBRY
 APPNAME ="LBRY"
+
 else ifeq ($(COIN),resistance)
 # Resistance
-DEFINES   += BIP44_COIN_TYPE=356  BIP44_COIN_TYPE_2=356 COIN_P2PKH_VERSION=7063 COIN_P2SH_VERSION=7068 COIN_FAMILY=1 COIN_COINID=\"Res\" COIN_COINID_HEADER=\"RES\" COIN_COINID_NAME=\"Res\" COIN_COINID_SHORT=\"RES\" COIN_KIND=COIN_KIND_RESISTANCE
+BIP44_COIN_TYPE=356  
+BIP44_COIN_TYPE_2=356 
+COIN_P2PKH_VERSION=7063 
+COIN_P2SH_VERSION=7068 
+COIN_FAMILY=1 
+COIN_COINID=\"Res\" 
+COIN_COINID_HEADER=\"RES\" 
+COIN_COINID_NAME=\"Res\" 
+COIN_COINID_SHORT=\"RES\" 
+COIN_KIND=COIN_KIND_RESISTANCE
 APPNAME ="Resistance"
+
 else ifeq ($(COIN),ravencoin)
 # Ravencoin
-DEFINES   += BIP44_COIN_TYPE=175  BIP44_COIN_TYPE_2=175 COIN_P2PKH_VERSION=60 COIN_P2SH_VERSION=122 COIN_FAMILY=1 COIN_COINID=\"Ravencoin\" COIN_COINID_HEADER=\"RAVENCOIN\" COIN_COINID_NAME=\"Ravencoin\" COIN_COINID_SHORT=\"RVN\" COIN_KIND=COIN_KIND_RAVENCOIN
+BIP44_COIN_TYPE=175  
+BIP44_COIN_TYPE_2=175 
+COIN_P2PKH_VERSION=60 
+COIN_P2SH_VERSION=122 
+COIN_FAMILY=1 
+COIN_COINID=\"Ravencoin\" 
+COIN_COINID_HEADER=\"RAVENCOIN\" 
+COIN_COINID_NAME=\"Ravencoin\" 
+COIN_COINID_SHORT=\"RVN\" 
+COIN_KIND=COIN_KIND_RAVENCOIN
 APPNAME ="Ravencoin"
+
 else ifeq ($(COIN),hydra_testnet)
 # Hydra testnet
-DEFINES   += BIP44_COIN_TYPE=0 BIP44_COIN_TYPE_2=0 COIN_P2PKH_VERSION=66 COIN_P2SH_VERSION=128 COIN_FAMILY=3 COIN_COINID=\"Hydra\" COIN_COINID_HEADER=\"HYDRA\" COIN_COINID_NAME=\"HYDRA\" COIN_COINID_SHORT=\"HYDRA\" COIN_NATIVE_SEGWIT_PREFIX=\"hc\" COIN_KIND=COIN_KIND_HYDRA COIN_FLAGS=FLAG_SEGWIT_CHANGE_SUPPORT
+BIP44_COIN_TYPE=0 
+BIP44_COIN_TYPE_2=0 
+COIN_P2PKH_VERSION=66 
+COIN_P2SH_VERSION=128 
+COIN_FAMILY=3 
+COIN_COINID=\"Hydra\" 
+COIN_COINID_HEADER=\"HYDRA\" 
+COIN_COINID_NAME=\"HYDRA\" 
+COIN_COINID_SHORT=\"HYDRA\" 
+COIN_NATIVE_SEGWIT_PREFIX=\"hc\" 
+COIN_KIND=COIN_KIND_HYDRA 
+COIN_FLAGS=FLAG_SEGWIT_CHANGE_SUPPORT
 APPNAME ="Hydra Test"
+APP_LOAD_PARAMS += --path "44'/609'"
+
 else ifeq ($(COIN),hydra)
 # Hydra mainnet
-DEFINES   += BIP44_COIN_TYPE=0 BIP44_COIN_TYPE_2=0 COIN_P2PKH_VERSION=40 COIN_P2SH_VERSION=63 COIN_FAMILY=3 COIN_COINID=\"Hydra\" COIN_COINID_HEADER=\"HYDRA\" COIN_COINID_NAME=\"HYDRA\" COIN_COINID_SHORT=\"HYDRA\" COIN_NATIVE_SEGWIT_PREFIX=\"hc\" COIN_KIND=COIN_KIND_HYDRA COIN_FLAGS=FLAG_SEGWIT_CHANGE_SUPPORT
+BIP44_COIN_TYPE=0 
+BIP44_COIN_TYPE_2=0 
+COIN_P2PKH_VERSION=40 
+COIN_P2SH_VERSION=63 
+COIN_FAMILY=3 
+COIN_COINID=\"Hydra\" 
+COIN_COINID_HEADER=\"HYDRA\" 
+COIN_COINID_NAME=\"HYDRA\" 
+COIN_COINID_SHORT=\"HYDRA\" 
+COIN_NATIVE_SEGWIT_PREFIX=\"hc\" 
+COIN_KIND=COIN_KIND_HYDRA 
+COIN_FLAGS=FLAG_SEGWIT_CHANGE_SUPPORT
 APPNAME ="Hydra"
-else
-ifeq ($(filter clean,$(MAKECMDGOALS)),)
+APP_LOAD_PARAMS += --path "44'/609'"
+
+else ifeq ($(filter clean,$(MAKECMDGOALS)),)
 $(error Unsupported COIN - use bitcoin_testnet, bitcoin, bitcoin_cash, bitcoin_gold, litecoin, dogecoin, dash, zcash, horizen, komodo, stratis, peercoin, pivx, viacoin, vertcoin, stealth, digibyte, bitcoin_private, firo, gamecredits, zclassic, xsn, nix, lbry, resistance, ravencoin, hydra, hydra_testnet, xrhodium)
 endif
-endif
 
-include $(BOLOS_SDK)/Makefile.standard_app
+include lib-app-bitcoin/Makefile
diff --git a/include/apdu_constants.h b/include/apdu_constants.h
deleted file mode 100644
index 1aa127d3..00000000
--- a/include/apdu_constants.h
+++ /dev/null
@@ -1,145 +0,0 @@
-/*******************************************************************************
-*   Ledger App - Bitcoin Wallet
-*   (c) 2016-2019 Ledger
-*
-*  Licensed under the Apache License, Version 2.0 (the "License");
-*  you may not use this file except in compliance with the License.
-*  You may obtain a copy of the License at
-*
-*      http://www.apache.org/licenses/LICENSE-2.0
-*
-*  Unless required by applicable law or agreed to in writing, software
-*  distributed under the License is distributed on an "AS IS" BASIS,
-*  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-*  See the License for the specific language governing permissions and
-*  limitations under the License.
-********************************************************************************/
-
-#ifndef APDU_CONSTANTS_H
-
-#define APDU_CONSTANTS_H
-
-#define CLA 0xE0
-#define ADM_CLA 0xD0
-#define NFCPAYMENT_CLA 0xF0
-
-#define INS_SETUP 0x20
-#define INS_VERIFY_PIN 0x22
-#define INS_GET_OPERATION_MODE 0x24
-#define INS_SET_OPERATION_MODE 0x26
-#define INS_SET_KEYBOARD_CFG 0x28
-#define INS_GET_WALLET_PUBLIC_KEY 0x40
-#define INS_GET_TRUSTED_INPUT 0x42
-#define INS_HASH_INPUT_START 0x44
-#define INS_HASH_INPUT_FINALIZE 0x46
-#define INS_HASH_SIGN 0x48
-#define INS_HASH_INPUT_FINALIZE_FULL 0x4A
-#define INS_GET_INTERNAL_CHAIN_INDEX 0x4C
-#define INS_SIGN_MESSAGE 0x4E
-#define INS_GET_TRANSACTION_LIMIT 0xA0
-#define INS_SET_TRANSACTION_LIMIT 0xA2
-#define INS_IMPORT_PRIVATE_KEY 0xB0
-#define INS_GET_PUBLIC_KEY 0xB2
-#define INS_DERIVE_BIP32_KEY 0xB4
-#define INS_SIGNVERIFY_IMMEDIATE 0xB6
-#define INS_GET_RANDOM 0xC0
-#define INS_GET_ATTESTATION 0xC2
-#define INS_GET_FIRMWARE_VERSION 0xC4
-#define INS_COMPOSE_MOFN_ADDRESS 0xC6
-#define INS_GET_POS_SEED 0xCA
-#define INS_DEBUG 0xD0
-
-#define INS_ADM_INIT_KEYS 0x20
-#define INS_ADM_INIT_ATTESTATION 0x22
-#define INS_ADM_GET_UPDATE_ID 0x24
-#define INS_ADM_SET_KEYCARD_SEED 0x26
-#define INS_ADM_FIRMWARE_UPDATE 0x42
-
-#define INS_SET_USER_KEYCARD 0x10
-#define INS_SETUP_SECURE_SCREEN 0x12
-#define INS_SET_ALTERNATE_COIN_VER 0x14
-#define INS_GET_COIN_VER 0x16
-
-#define INS_STORE_TRUST_ROOT_BIP70 0x30
-#define INS_CREATE_CERTIFICATE_BIP70 0x32
-#define INS_CREATE_PAYMENT_REQ_BIP70 0x34
-#define INS_PROCESS_CERTIFICATE_BIP70 0x36
-#define INS_PARSE_PAYMENT_REQ_BIP70 0x38
-#define INS_HASH_INPUT_FINALIZE_BIP70 0x3A
-#define INS_ADM_SET_ROOT_BIP70 0x28
-#define INS_ADM_SET_BIP39_SHUFFLE 0x2A
-
-#define INS_NFCPAYMENT_SET_CONFIG 0x20
-#define INS_NFCPAYMENT_GET_CONFIG 0x22
-#define INS_NFCPAYMENT_STORE_UTXO 0x40
-#define INS_NFCPAYMENT_STORE_SCRIPT 0x42
-#define INS_NFCPAYMENT_GET_UTXO 0x44
-#define INS_NFCPAYMENT_DELETE_UTXO 0x46
-#define INS_NFCPAYMENT_GET_PAYMENT_TX 0x50
-#define INS_NFCPAYMENT_GET_LAST_TX 0x52
-#define INS_NFCPAYMENT_CONFIRM_TX 0x54
-#define INS_NFCPAYMENT_CONFIRM_CHANGE 0x56
-#define INS_NFCPAYMENT_GET_LAST_STAT 0x58
-#define INS_NFCPAYMENT_GET_DATA 0xC0
-
-#define SW_PIN_REMAINING_ATTEMPTS 0x63C0
-#define SW_INCORRECT_LENGTH 0x6700
-#define SW_COMMAND_INCOMPATIBLE_FILE_STRUCTURE 0x6981
-#define SW_SECURITY_STATUS_NOT_SATISFIED 0x6982
-#define SW_CONDITIONS_OF_USE_NOT_SATISFIED 0x6985
-#define SW_INCORRECT_DATA 0x6A80
-#define SW_NOT_ENOUGH_MEMORY_SPACE 0x6A84
-#define SW_REFERENCED_DATA_NOT_FOUND 0x6A88
-#define SW_FILE_ALREADY_EXISTS 0x6A89
-#define SW_SWAP_WITHOUT_TRUSTED_INPUTS 0x6A8A
-#define SW_INCORRECT_P1_P2 0x6B00
-#define SW_INS_NOT_SUPPORTED 0x6D00
-#define SW_CLA_NOT_SUPPORTED 0x6E00
-#define SW_TECHNICAL_PROBLEM 0x6F00
-#define SW_OK 0x9000
-#define SW_MEMORY_PROBLEM 0x9240
-#define SW_NO_EF_SELECTED 0x9400
-#define SW_INVALID_OFFSET 0x9402
-#define SW_FILE_NOT_FOUND 0x9404
-#define SW_INCONSISTENT_FILE 0x9408
-#define SW_ALGORITHM_NOT_SUPPORTED 0x9484
-#define SW_INVALID_KCV 0x9485
-#define SW_CODE_NOT_INITIALIZED 0x9802
-#define SW_ACCESS_CONDITION_NOT_FULFILLED 0x9804
-#define SW_CONTRADICTION_SECRET_CODE_STATUS 0x9808
-#define SW_CONTRADICTION_INVALIDATION 0x9810
-#define SW_CODE_BLOCKED 0x9840
-#define SW_MAX_VALUE_REACHED 0x9850
-#define SW_GP_AUTH_FAILED 0x6300
-#define SW_LICENSING 0x6F42
-#define SW_HALTED 0x6FAA
-#define SW_APP_HALTED SW_CONDITIONS_OF_USE_NOT_SATISFIED
-
-#define ISO_OFFSET_CLA 0x00
-#define ISO_OFFSET_INS 0x01
-#define ISO_OFFSET_P1 0x02
-#define ISO_OFFSET_P2 0x03
-#define ISO_OFFSET_LC 0x04
-#define ISO_OFFSET_CDATA 0x05
-
-#define BITID_DERIVE 0xB11D
-#define BITID_DERIVE_MULTIPLE 0xB11E
-
-#include "os.h"
-#include "secure_value.h"
-
-void commit_operation_mode(secu8 operationMode);
-
-unsigned short apdu_get_wallet_public_key(void);
-unsigned short apdu_get_trusted_input(void);
-unsigned short apdu_hash_input_start(void);
-unsigned short apdu_hash_input_finalize(void);
-unsigned short apdu_hash_sign(void);
-unsigned short apdu_hash_input_finalize_full(void);
-unsigned short apdu_sign_message(void);
-
-unsigned short apdu_get_firmware_version(void);
-
-unsigned short apdu_get_coin_version(void);
-
-#endif
diff --git a/include/config.h b/include/config.h
deleted file mode 100644
index dac4e214..00000000
--- a/include/config.h
+++ /dev/null
@@ -1,28 +0,0 @@
-/*******************************************************************************
-*   Ledger App - Bitcoin Wallet
-*   (c) 2016-2019 Ledger
-*
-*  Licensed under the Apache License, Version 2.0 (the "License");
-*  you may not use this file except in compliance with the License.
-*  You may obtain a copy of the License at
-*
-*      http://www.apache.org/licenses/LICENSE-2.0
-*
-*  Unless required by applicable law or agreed to in writing, software
-*  distributed under the License is distributed on an "AS IS" BASIS,
-*  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-*  See the License for the specific language governing permissions and
-*  limitations under the License.
-********************************************************************************/
-
-#ifndef CONFIG_H
-
-#define CONFIG_H
-
-//#define DISABLE_SECURE_VALUE
-
-#define VERBOSE_6F
-
-#define os_crc cx_crc16
-
-#endif
diff --git a/include/filesystem.h b/include/filesystem.h
deleted file mode 100644
index fe994dc9..00000000
--- a/include/filesystem.h
+++ /dev/null
@@ -1,86 +0,0 @@
-/*******************************************************************************
-*   Ledger App - Bitcoin Wallet
-*   (c) 2016-2019 Ledger
-*
-*  Licensed under the Apache License, Version 2.0 (the "License");
-*  you may not use this file except in compliance with the License.
-*  You may obtain a copy of the License at
-*
-*      http://www.apache.org/licenses/LICENSE-2.0
-*
-*  Unless required by applicable law or agreed to in writing, software
-*  distributed under the License is distributed on an "AS IS" BASIS,
-*  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-*  See the License for the specific language governing permissions and
-*  limitations under the License.
-********************************************************************************/
-
-#ifndef FS_H
-
-#define FS_H
-
-#include "os.h"
-#include "config.h"
-#include "context.h"
-#include "filesystem_tx.h"
-
-enum supported_modes_e {
-    SUPPORTED_MODE_WALLET = 0x01,
-    SUPPORTED_MODE_RELAXED_WALLET = 0x02,
-    SUPPORTED_MODE_SERVER = 0x04,
-    SUPPORTED_MODE_DEVELOPER = 0x08
-};
-
-enum family_e {
-    FAMILY_BITCOIN = 0x01,
-    FAMILY_PEERCOIN = 0x02,
-    FAMILY_STEALTH = 0x04
-};
-
-struct config_s {
-    secu8 supportedModes;
-    secu8 operationMode;
-    unsigned char options;
-    // unsigned short payToAddressVersion;
-    // unsigned short payToScriptHashVersion;
-    // unsigned char coinFamily;
-    // /** Current Coin ID */
-    // unsigned char coinId[MAX_COIN_ID];
-    // /** Current short Coin ID */
-    // unsigned char shortCoinId[MAX_SHORT_COIN_ID];
-    // /** Current Coin ID length */
-    // unsigned char coinIdLength;
-    // /** Current short Coin ID length */
-    // unsigned char shortCoinIdLength;
-};
-typedef struct config_s config_t;
-
-typedef struct backup_area_s {
-    config_t config;
-    uint8_t trustedinput_key[32];
-} backup_area_t;
-
-typedef struct storage_s {
-    unsigned char storageInitialized;
-
-    unsigned char config_valid;
-    backup_area_t bkp;
-
-    unsigned char fidoTransport;
-
-    uint8_t pubKeyRequestRestriction;
-
-} storage_t;
-
-// the global nvram memory variable
-#if 0
-extern storage_t N_real;
-#define N_btchip (*(storage_t *)PIC(&N_real))
-#else
-extern storage_t const N_real;
-#define N_btchip (*(volatile storage_t *)PIC(&N_real))
-#endif
-
-void set_operation_mode(unsigned char operationMode);
-
-#endif
diff --git a/include/secure_value.h b/include/secure_value.h
deleted file mode 100644
index 8052084a..00000000
--- a/include/secure_value.h
+++ /dev/null
@@ -1,50 +0,0 @@
-/*******************************************************************************
-*   Ledger App - Bitcoin Wallet
-*   (c) 2016-2019 Ledger
-*
-*  Licensed under the Apache License, Version 2.0 (the "License");
-*  you may not use this file except in compliance with the License.
-*  You may obtain a copy of the License at
-*
-*      http://www.apache.org/licenses/LICENSE-2.0
-*
-*  Unless required by applicable law or agreed to in writing, software
-*  distributed under the License is distributed on an "AS IS" BASIS,
-*  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-*  See the License for the specific language governing permissions and
-*  limitations under the License.
-********************************************************************************/
-
-#ifndef SECURE_VALUE_H
-
-#define SECURE_VALUE_H
-
-#include "os.h"
-
-typedef unsigned short secu8;
-typedef unsigned long int secu16;
-
-void sbSet(secu8 *target, unsigned char source);
-void sbCheck(secu8 source);
-void ssSet(secu16 *target, unsigned short source);
-void ssCheck(secu16 source);
-
-#define SB_GET(x) ((unsigned char)x)
-
-#define SB_SET(x, y) sbSet(&x, y);
-
-#define SB_CHECK(x) sbCheck(x);
-
-#define SS_GET(x) ((unsigned short)x)
-
-#define SS_SET(x, y) ssSet(&x, y);
-
-#define SS_CHECK(x) ssCheck(x);
-
-#define SSEC_DEF(x) unsigned char x = 0;
-#define SSEC_INC(x) x++;
-#define SSEC_CHECK(x, value)                                                   \
-    if (x != value)                                                            \
-        reset();
-
-#endif
diff --git a/include/swap_lib_calls.h b/include/swap_lib_calls.h
deleted file mode 100644
index 806e5f09..00000000
--- a/include/swap_lib_calls.h
+++ /dev/null
@@ -1,81 +0,0 @@
-#pragma once
-
-/* This file is the shared API between Exchange and the apps started in Library mode for Exchange
- *
- * DO NOT MODIFY THIS FILE IN APPLICATIONS OTHER THAN EXCHANGE
- * On modification in Exchange, forward the changes to all applications supporting Exchange
- */
-
-#include "stdbool.h"
-#include "stdint.h"
-#include "context.h"
-
-#define RUN_APPLICATION 1
-
-#define SIGN_TRANSACTION 2
-
-#define CHECK_ADDRESS 3
-
-#define GET_PRINTABLE_AMOUNT 4
-
-/*
- * Amounts are stored as bytes, with a max size of 16 (see protobuf
- * specifications). Max 16B integer is 340282366920938463463374607431768211455
- * in decimal, which is a 32-long char string.
- * The printable amount also contains spaces, the ticker symbol (with variable
- * size, up to 12 in Ethereum for instance) and a terminating null byte, so 50
- * bytes total should be a fair maximum.
- */
-#define MAX_PRINTABLE_AMOUNT_SIZE 50
-
-// structure that should be send to specific coin application to get address
-typedef struct check_address_parameters_s {
-    // IN
-    uint8_t *coin_configuration;
-    uint8_t coin_configuration_length;
-    // serialized path, segwit, version prefix, hash used, dictionary etc.
-    // fields and serialization format depends on specific coin app
-    uint8_t *address_parameters;
-    uint8_t address_parameters_length;
-    char *address_to_check;
-    char *extra_id_to_check;
-    // OUT
-    int result;
-} check_address_parameters_t;
-
-// structure that should be send to specific coin application to get printable amount
-typedef struct get_printable_amount_parameters_s {
-    // IN
-    uint8_t *coin_configuration;
-    uint8_t coin_configuration_length;
-    uint8_t *amount;
-    uint8_t amount_length;
-    bool is_fee;
-    // OUT
-    char printable_amount[MAX_PRINTABLE_AMOUNT_SIZE];
-} get_printable_amount_parameters_t;
-
-typedef struct create_transaction_parameters_s {
-    // IN
-    uint8_t *coin_configuration;
-    uint8_t coin_configuration_length;
-    uint8_t *amount;
-    uint8_t amount_length;
-    uint8_t *fee_amount;
-    uint8_t fee_amount_length;
-    char *destination_address;
-    char *destination_address_extra_id;
-    // OUT
-    uint8_t result;
-} create_transaction_parameters_t;
-
-typedef struct libargs_s {
-    unsigned int id;
-    unsigned int command;
-    altcoin_config_t *coin_config;
-    union {
-        check_address_parameters_t *check_address;
-        create_transaction_parameters_t *create_transaction;
-        get_printable_amount_parameters_t *get_printable_amount;
-    };
-} libargs_t;
diff --git a/lib-app-bitcoin/Makefile b/lib-app-bitcoin/Makefile
new file mode 100644
index 00000000..b19b0cc3
--- /dev/null
+++ b/lib-app-bitcoin/Makefile
@@ -0,0 +1,145 @@
+# ****************************************************************************
+#    Ledger App Bitcoin
+#    (c) 2023 Ledger SAS.
+#
+#   Licensed under the Apache License, Version 2.0 (the "License");
+#   you may not use this file except in compliance with the License.
+#   You may obtain a copy of the License at
+#
+#       http://www.apache.org/licenses/LICENSE-2.0
+#
+#   Unless required by applicable law or agreed to in writing, software
+#   distributed under the License is distributed on an "AS IS" BASIS,
+#   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+#   See the License for the specific language governing permissions and
+#   limitations under the License.
+# ****************************************************************************
+
+ifeq ($(BOLOS_SDK),)
+$(error Environment variable BOLOS_SDK is not set)
+endif
+include $(BOLOS_SDK)/Makefile.defines
+
+########################################
+#        Mandatory configuration       #
+########################################
+# Name is defined later
+
+ifeq ($(APPVERSION_M),)
+$(error APPVERSION_M must be defined)
+endif
+ifeq ($(APPVERSION_N),)
+$(error APPVERSION_N must be defined)
+endif
+ifeq ($(APPVERSION_P),)
+$(error APPVERSION_P must be defined)
+endif
+
+APPVERSION = "$(APPVERSION_M).$(APPVERSION_N).$(APPVERSION_P)"
+
+APP_SOURCE_PATH += lib-app-bitcoin/
+
+ICON_NANOS = icons/nanos_app_$(COIN).gif
+ICON_NANOX = icons/nanox_app_$(COIN).gif
+ICON_NANOSP = icons/nanox_app_$(COIN).gif
+ICON_STAX = icons/stax_app_$(COIN).gif
+
+ifeq ($(TARGET_NAME),TARGET_STAX)
+DEFINES += COIN_ICON=C_$(COIN)_64px
+DEFINES += COIN_ICON_BITMAP=C_$(COIN)_64px_bitmap
+endif
+
+# Application allowed derivation curves.
+CURVE_APP_LOAD_PARAMS = secp256k1
+
+# Application allowed derivation paths.
+PATH_APP_LOAD_PARAMS = ""
+
+HAVE_APPLICATION_FLAG_DERIVE_MASTER = 1
+HAVE_APPLICATION_FLAG_LIBRARY = 1
+
+VARIANT_PARAM = COIN
+
+ENABLE_BLUETOOTH = 1
+ENABLE_NBGL_QRCODE = 1
+ENABLE_SWAP = 1
+
+ifeq ($(TARGET_NAME),TARGET_STAX)
+DEFINES += COIN_ICON=C_$(COIN)_64px
+DEFINES += COIN_ICON_BITMAP=C_$(COIN)_64px_bitmap
+endif
+
+ifndef BIP44_COIN_TYPE
+$(error BIP44_COIN_TYPE must be defined)
+endif
+
+ifndef BIP44_COIN_TYPE_2
+$(error BIP44_COIN_TYPE_2 must be defined)
+endif
+
+ifndef COIN_P2PKH_VERSION
+$(error COIN_P2PKH_VERSION must be defined)
+endif
+
+ifndef COIN_P2SH_VERSION
+$(error COIN_P2SH_VERSION must be defined)
+endif
+
+ifndef COIN_FAMILY
+$(error COIN_FAMILY must be defined)
+endif
+
+ifndef COIN_COINID
+$(error COIN_COINID must be defined)
+endif
+
+ifndef COIN_COINID_HEADER
+$(error COIN_COINID_HEADER must be defined)
+endif
+
+ifndef COIN_COINID_NAME
+$(error COIN_COINID_NAME must be defined)
+endif
+
+ifndef COIN_COINID_SHORT
+$(error COIN_COINID_SHORT must be defined)
+endif
+
+ifndef COIN_NATIVE_SEGWIT_PREFIX
+$(info COIN_NATIVE_SEGWIT_PREFIX automatically set to 0)
+COIN_NATIVE_SEGWIT_PREFIX=0
+endif
+
+ifndef COIN_KIND
+$(error COIN_KIND must be defined)
+endif
+
+ifndef COIN_FLAGS
+$(info COIN_FLAGS automatically set to 0)
+COIN_FLAGS=0
+endif
+
+ifndef COIN_FORKID
+$(info COIN_FORKID automatically set to 0)
+COIN_FORKID=0
+endif
+
+ifeq ($(APPNAME),)
+$(error APPNAME must be defined)
+endif
+
+DEFINES +=BIP44_COIN_TYPE=$(BIP44_COIN_TYPE)
+DEFINES +=BIP44_COIN_TYPE_2=$(BIP44_COIN_TYPE_2)
+DEFINES +=COIN_P2PKH_VERSION=$(COIN_P2PKH_VERSION)
+DEFINES +=COIN_P2SH_VERSION=$(COIN_P2SH_VERSION)
+DEFINES +=COIN_FAMILY=$(COIN_FAMILY)
+DEFINES +=COIN_COINID=$(COIN_COINID)
+DEFINES +=COIN_COINID_HEADER=$(COIN_COINID_HEADER)
+DEFINES +=COIN_COINID_NAME=$(COIN_COINID_NAME)
+DEFINES +=COIN_COINID_SHORT=$(COIN_COINID_SHORT)
+DEFINES +=COIN_NATIVE_SEGWIT_PREFIX=$(COIN_NATIVE_SEGWIT_PREFIX)
+DEFINES +=COIN_KIND=$(COIN_KIND)
+DEFINES +=COIN_FLAGS=$(COIN_FLAGS)
+DEFINES +=COIN_FORKID=$(COIN_FORKID)
+
+include $(BOLOS_SDK)/Makefile.standard_app
diff --git a/lib-app-bitcoin/apdu/apdu_constants.h b/lib-app-bitcoin/apdu/apdu_constants.h
new file mode 100644
index 00000000..f5265425
--- /dev/null
+++ b/lib-app-bitcoin/apdu/apdu_constants.h
@@ -0,0 +1,60 @@
+/*******************************************************************************
+*   Ledger App - Bitcoin Wallet
+*   (c) 2016-2019 Ledger
+*
+*  Licensed under the Apache License, Version 2.0 (the "License");
+*  you may not use this file except in compliance with the License.
+*  You may obtain a copy of the License at
+*
+*      http://www.apache.org/licenses/LICENSE-2.0
+*
+*  Unless required by applicable law or agreed to in writing, software
+*  distributed under the License is distributed on an "AS IS" BASIS,
+*  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+*  See the License for the specific language governing permissions and
+*  limitations under the License.
+********************************************************************************/
+#pragma once
+
+#include "os.h"
+#include "buffer.h"
+#include "macros.h"
+
+#define CLA 0xE0
+
+#define INS_GET_WALLET_PUBLIC_KEY 0x40
+#define INS_GET_TRUSTED_INPUT 0x42
+#define INS_HASH_INPUT_START 0x44
+#define INS_HASH_SIGN 0x48
+#define INS_HASH_INPUT_FINALIZE_FULL 0x4A
+#define INS_SIGN_MESSAGE 0x4E
+#define INS_GET_FIRMWARE_VERSION 0xC4
+#define INS_GET_COIN_VER 0x16
+
+#define SW_INCORRECT_LENGTH 0x6700
+#define SW_SECURITY_STATUS_NOT_SATISFIED 0x6982
+#define SW_CONDITIONS_OF_USE_NOT_SATISFIED 0x6985
+#define SW_INCORRECT_DATA 0x6A80
+#define SW_SWAP_WITHOUT_TRUSTED_INPUTS 0x6A8A
+#define SW_INCORRECT_P1_P2 0x6B00
+#define SW_INS_NOT_SUPPORTED 0x6D00
+#define SW_CLA_NOT_SUPPORTED 0x6E00
+#define SW_TECHNICAL_PROBLEM 0x6F00
+#define SW_TECHNICAL_PROBLEM_2 0x6F0F
+#define SW_OK 0x9000
+
+#define BITID_DERIVE 0xB11D
+#define BITID_DERIVE_MULTIPLE 0xB11E
+
+#define ZCASH_USING_OVERWINTER 0x01
+#define ZCASH_USING_OVERWINTER_SAPLING 0x02
+
+unsigned short handler_sign_message(buffer_t* buffer, uint8_t p1, uint8_t p2);
+unsigned short handler_hash_sign(buffer_t* buffer, uint8_t p1, uint8_t p2);
+unsigned short handler_hash_input_start(buffer_t* buffer, uint8_t p1, uint8_t p2);
+unsigned short handler_hash_input_finalize_full(buffer_t* buffer, uint8_t p1, uint8_t p2);
+unsigned short handler_get_wallet_public_key(buffer_t* buffer, uint8_t p1, uint8_t p2);
+unsigned short handler_get_trusted_input(buffer_t* buffer, uint8_t p1, uint8_t p2);
+unsigned short handler_get_firmware_version(void);
+unsigned short handler_get_coin_version(void);
+
diff --git a/lib-app-bitcoin/apdu/dispatcher.c b/lib-app-bitcoin/apdu/dispatcher.c
new file mode 100644
index 00000000..7e2c6c0e
--- /dev/null
+++ b/lib-app-bitcoin/apdu/dispatcher.c
@@ -0,0 +1,117 @@
+/*****************************************************************************
+ *   Ledger App Boilerplate.
+ *   (c) 2020 Ledger SAS.
+ *
+ *  Licensed under the Apache License, Version 2.0 (the "License");
+ *  you may not use this file except in compliance with the License.
+ *  You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ *  Unless required by applicable law or agreed to in writing, software
+ *  distributed under the License is distributed on an "AS IS" BASIS,
+ *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ *  See the License for the specific language governing permissions and
+ *  limitations under the License.
+ *****************************************************************************/
+
+#include <stdint.h>
+#include <stdbool.h>
+
+#include "buffer.h"
+#include "io.h"
+#include "ledger_assert.h"
+
+#include "dispatcher.h"
+#include "apdu_constants.h"
+
+int apdu_dispatcher(const command_t *cmd) {
+    LEDGER_ASSERT(cmd != NULL, "NULL cmd");
+
+    if (cmd->cla != CLA) {
+        return io_send_sw(SW_CLA_NOT_SUPPORTED);
+    }
+
+    buffer_t buf = {0};
+
+    switch (cmd->ins) {
+        case INS_GET_WALLET_PUBLIC_KEY:
+            PRINTF("Get wallet public key\n");
+            if (!cmd->data) {
+                return io_send_sw(SW_INCORRECT_LENGTH);
+            }
+            buf.ptr = cmd->data;
+            buf.size = cmd->lc;
+            buf.offset = 0;
+            return handler_get_wallet_public_key(&buf, cmd->p1, cmd->p2);
+
+        case INS_GET_TRUSTED_INPUT:
+            PRINTF("Get trusted input\n");
+            if (!cmd->data) {
+                return io_send_sw(SW_INCORRECT_LENGTH);
+            }
+
+            buf.ptr = cmd->data;
+            buf.size = cmd->lc;
+            buf.offset = 0;
+            return handler_get_trusted_input(&buf, cmd->p1, cmd->p2);
+
+        case INS_HASH_INPUT_START:
+            PRINTF("Hash input start\n");
+            if (!cmd->data) {
+                return io_send_sw(SW_INCORRECT_LENGTH);
+            }
+
+            buf.ptr = cmd->data;
+            buf.size = cmd->lc;
+            buf.offset = 0;
+            return handler_hash_input_start(&buf, cmd->p1, cmd->p2);
+
+        case INS_HASH_SIGN:
+            PRINTF("Hash sign\n");
+            if (!cmd->data) {
+                return io_send_sw(SW_INCORRECT_LENGTH);
+            }
+
+            buf.ptr = cmd->data;
+            buf.size = cmd->lc;
+            buf.offset = 0;
+            return handler_hash_sign(&buf, cmd->p1, cmd->p2);
+
+        case INS_HASH_INPUT_FINALIZE_FULL:
+            PRINTF("Hash input finalize full\n");
+            if (!cmd->data) {
+                return io_send_sw(SW_INCORRECT_LENGTH);
+            }
+
+            buf.ptr = cmd->data;
+            buf.size = cmd->lc;
+            buf.offset = 0;
+            return handler_hash_input_finalize_full(&buf, cmd->p1, cmd->p2);
+
+        case INS_SIGN_MESSAGE:
+            PRINTF("Sign message\n");
+            if (!cmd->data) {
+                return io_send_sw(SW_INCORRECT_LENGTH);
+            }
+
+            buf.ptr = cmd->data;
+            buf.size = cmd->lc;
+            buf.offset = 0;
+            return handler_sign_message(&buf, cmd->p1, cmd->p2);
+
+        case INS_GET_FIRMWARE_VERSION:
+            PRINTF("Get firmware version\n");
+
+            return handler_get_firmware_version();
+            
+        case INS_GET_COIN_VER:
+            PRINTF("Get coin version\n");
+
+            return handler_get_coin_version();
+
+        default:
+            PRINTF("Instruction not supported\n");
+            return io_send_sw(SW_INS_NOT_SUPPORTED);
+    }
+}
diff --git a/lib-app-bitcoin/apdu/dispatcher.h b/lib-app-bitcoin/apdu/dispatcher.h
new file mode 100644
index 00000000..36e1f60c
--- /dev/null
+++ b/lib-app-bitcoin/apdu/dispatcher.h
@@ -0,0 +1,14 @@
+#pragma once
+
+#include "parser.h"
+
+/**
+ * Dispatch APDU command received to the right handler.
+ *
+ * @param[in] cmd
+ *   Structured APDU command (CLA, INS, P1, P2, Lc, Command data).
+ *
+ * @return zero or positive integer if success, negative integer otherwise.
+ *
+ */
+int apdu_dispatcher(const command_t *cmd);
diff --git a/lib-app-bitcoin/app_main.c b/lib-app-bitcoin/app_main.c
new file mode 100644
index 00000000..d25e5be5
--- /dev/null
+++ b/lib-app-bitcoin/app_main.c
@@ -0,0 +1,72 @@
+/*******************************************************************************
+*   Ledger App - Bitcoin Wallet
+*   (c) 2016-2019 Ledger
+*
+*  Licensed under the Apache License, Version 2.0 (the "License");
+*  you may not use this file except in compliance with the License.
+*  You may obtain a copy of the License at
+*
+*      http://www.apache.org/licenses/LICENSE-2.0
+*
+*  Unless required by applicable law or agreed to in writing, software
+*  distributed under the License is distributed on an "AS IS" BASIS,
+*  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+*  See the License for the specific language governing permissions and
+*  limitations under the License.
+********************************************************************************/
+#include "swap.h"
+#include "io.h"
+
+#include "context.h"
+#include "apdu_constants.h"
+#include "dispatcher.h"
+#include "ui.h"
+
+
+void app_main(void) {
+    // Structured APDU command
+    command_t cmd;
+
+    io_init();
+
+    if (!G_called_from_swap) {
+        ui_idle_flow();
+    }
+
+    context_init();
+
+    for (;;) {
+        // Length of APDU command received in G_io_apdu_buffer
+        int input_len = 0;
+
+        // Receive command bytes in G_io_apdu_buffer
+        if ((input_len = io_recv_command()) < 0) {
+            PRINTF("=> io_recv_command failure\n");
+            return;
+        }
+
+        // Parse APDU command from G_io_apdu_buffer
+        if (!apdu_parser(&cmd, G_io_apdu_buffer, input_len)) {
+            PRINTF("=> /!\\ BAD LENGTH: %.*H\n", input_len, G_io_apdu_buffer);
+            io_send_sw(SW_INCORRECT_LENGTH);
+            continue;
+        }
+
+        PRINTF("=> CLA=%02X | INS=%02X | P1=%02X | P2=%02X | Lc=%02X | CData=%.*H\n",
+                cmd.cla,
+                cmd.ins,
+                cmd.p1,
+                cmd.p2,
+                cmd.lc,
+                cmd.lc,
+                cmd.data);
+
+        context_D.outLength = 0;
+
+        // Dispatch structured APDU command to handler
+        if (apdu_dispatcher(&cmd) < 0) {
+            PRINTF("=> apdu_dispatcher failure\n");
+            return;
+        }
+    }
+}
diff --git a/src/context.c b/lib-app-bitcoin/context.c
similarity index 93%
rename from src/context.c
rename to lib-app-bitcoin/context.c
index 3ff49151..8fff1710 100644
--- a/src/context.c
+++ b/lib-app-bitcoin/context.c
@@ -15,10 +15,11 @@
 *  limitations under the License.
 ********************************************************************************/
 
-#include "internal.h"
-#include "swap.h"
+#include "context.h"
+#include "filesystem.h"
 
-void autosetup(void);
+context_t context_D;
+storage_t const N_real;
 
 /**
  * Initialize the application context on boot
@@ -27,7 +28,6 @@ void context_init() {
     PRINTF("Context init\n");
     PRINTF("Backup size %d\n", sizeof(N_btchip.bkp));
     memset(&context_D, 0, sizeof(context_D));
-    G_called_from_swap = 0;
     context_D.currentOutputOffset = 0;
     context_D.outputParsingState = OUTPUT_PARSING_NUMBER_OUTPUTS;
     memset(context_D.totalOutputAmount, 0,
@@ -35,3 +35,4 @@ void context_init() {
     context_D.changeOutputFound = 0;
     context_D.segwitWarningSeen = 0;
 }
+
diff --git a/include/context.h b/lib-app-bitcoin/context.h
similarity index 91%
rename from include/context.h
rename to lib-app-bitcoin/context.h
index 4f23f4db..0b000e00 100644
--- a/include/context.h
+++ b/lib-app-bitcoin/context.h
@@ -15,13 +15,10 @@
 *  limitations under the License.
 ********************************************************************************/
 
-#ifndef CONTEXT_H
-
-#define CONTEXT_H
+#pragma once
 
 #include "os.h"
 #include "cx.h"
-#include "secure_value.h"
 #include "filesystem_tx.h"
 #ifdef HAVE_NBGL
 #include "nbgl_types.h"
@@ -33,27 +30,6 @@
 #define MAX_SHORT_COIN_ID 5
 
 #define MAGIC_TRUSTED_INPUT 0x32
-#define MAGIC_DEV_KEY 0x01
-
-#define ZCASH_USING_OVERWINTER 0x01
-#define ZCASH_USING_OVERWINTER_SAPLING 0x02
-
-enum modes_e {
-    MODE_ISSUER = 0x00,
-    MODE_SETUP_NEEDED = 0xff,
-    MODE_WALLET = 0x01,
-    MODE_RELAXED_WALLET = 0x02,
-    MODE_SERVER = 0x04,
-    MODE_DEVELOPER = 0x08,
-};
-
-enum options_e {
-    OPTION_UNCOMPRESSED_KEYS = 0x01,
-    OPTION_DETERMINISTIC_SIGNATURE = 0x02,
-    OPTION_FREE_SIGHASHTYPE = 0x04,
-    OPTION_SKIP_2FA_P2SH = 0x08,
-    OPTION_ALLOW_ARBITRARY_CHANGE = 0x10
-};
 
 /**
  * Current state of an untrusted transaction hashing
@@ -156,8 +132,6 @@ struct tmp_output_s {
 typedef struct tmp_output_s tmp_output_t;
 
 struct context_s {
-    /** Flag if dongle has been halted */
-    secu8 halted;
     /** Index of the output to convert into a trusted input in a transaction */
     unsigned long int trustedInputIndex;
     /** (Integrity protected) transaction context */
@@ -200,9 +174,6 @@ struct context_s {
     /** Length of the outgoing command */
     unsigned short outLength;
 
-    /** IO flags to reply with at the end of an APDU handler */
-    unsigned char io_flags;
-
     /** Status Word of the response */
     unsigned short sw;
 
@@ -284,4 +255,4 @@ typedef enum coin_kind_e {
 
 void context_init(void);
 
-#endif
+extern context_t context_D;
diff --git a/lib-app-bitcoin/customizable_helpers.c b/lib-app-bitcoin/customizable_helpers.c
new file mode 100644
index 00000000..78e70a39
--- /dev/null
+++ b/lib-app-bitcoin/customizable_helpers.c
@@ -0,0 +1,151 @@
+/*******************************************************************************
+*   Ledger App - Bitcoin Wallet
+*   (c) 2016-2019 Ledger
+*
+*  Licensed under the Apache License, Version 2.0 (the "License");
+*  you may not use this file except in compliance with the License.
+*  You may obtain a copy of the License at
+*
+*      http://www.apache.org/licenses/LICENSE-2.0
+*
+*  Unless required by applicable law or agreed to in writing, software
+*  distributed under the License is distributed on an "AS IS" BASIS,
+*  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+*  See the License for the specific language governing permissions and
+*  limitations under the License.
+********************************************************************************/
+#include "macros.h"
+
+#include "context.h"
+#include "customizable_helpers.h"
+
+const unsigned char TRANSACTION_OUTPUT_SCRIPT_PRE[] = {
+    0x19, 0x76, 0xA9,
+    0x14}; // script length, OP_DUP, OP_HASH160, address length
+const unsigned char TRANSACTION_OUTPUT_SCRIPT_POST[] = {
+    0x88, 0xAC}; // OP_EQUALVERIFY, OP_CHECKSIG
+
+const unsigned char TRANSACTION_OUTPUT_SCRIPT_P2SH_PRE[] = {
+    0x17, 0xA9, 0x14}; // script length, OP_HASH160, address length
+const unsigned char TRANSACTION_OUTPUT_SCRIPT_P2SH_POST[] = {0x87}; // OP_EQUAL
+
+const unsigned char ZEN_TRANSACTION_OUTPUT_SCRIPT_P2SH_PRE[] = {
+        0x3D, 0xA9,
+        0x14}; // script length, OP_HASH160, address length
+
+const unsigned char ZEN_TRANSACTION_OUTPUT_SCRIPT_P2SH_POST[] = {
+        0x87, // OP_EQUAL
+        0x20, 0x9E, 0xC9, 0x84, 0x5A, 0xCB, 0x02, 0xFA, 0XB2, 0X4E,
+        0x1C, 0x03, 0x68, 0xB3, 0xB5, 0x17, 0xC1, 0xA4, 0x48, 0x8F,
+        0xBA, 0x97, 0xF0, 0xE3, 0x45, 0x9A, 0xC0, 0x53, 0xEA, 0x01,
+        0x00, 0x00, 0x00, // ParamHash
+        0x03, // Push 3 bytes to stack to make ParamHeight line up properly
+        0xC0, 0x1F, 0x02, // ParamHeight (139200) -> hex -> endianness swapped
+        0xB4};            // OP_CHECKBLOCKATHEIGHT
+
+const unsigned char TRANSACTION_OUTPUT_SCRIPT_P2WPKH_PRE[] = {0x16, 0x00, 0x14};
+const unsigned char TRANSACTION_OUTPUT_SCRIPT_P2WSH_PRE[] = {0x22, 0x00, 0x20};
+
+const unsigned char ZEN_OUTPUT_SCRIPT_PRE[] = {
+    0x3F, 0x76, 0xA9,
+    0x14}; // script length, OP_DUP, OP_HASH160, address length
+const unsigned char ZEN_OUTPUT_SCRIPT_POST[] = {
+    0x88, 0xAC, // OP_EQUALVERIFY, OP_CHECKSIG
+    0x20, 0x9e, 0xc9, 0x84, 0x5a, 0xcb, 0x02, 0xfa, 0xb2, 0x4e, 0x1c, 0x03,
+    0x68, 0xb3, 0xb5, 0x17, 0xc1, 0xa4, 0x48, 0x8f, 0xba, 0x97, 0xf0, 0xe3,
+    0x45, 0x9a, 0xc0, 0x53, 0xea, 0x01, 0x00, 0x00, 0x00, // ParamHash
+    0x03, // Push 3 bytes to stack to make ParamHeight line up properly
+    0xc0, 0x1f, 0x02, // ParamHeight (139200) -> hex -> endianness swapped
+    0xb4              // OP_CHECKBLOCKATHEIGHT
+};                    // BIP0115 Replay Protection
+
+WEAK unsigned char output_script_is_regular(unsigned char *buffer) {
+    if (COIN_NATIVE_SEGWIT_PREFIX) {
+        if ((memcmp(buffer, TRANSACTION_OUTPUT_SCRIPT_P2WPKH_PRE,
+                       sizeof(TRANSACTION_OUTPUT_SCRIPT_P2WPKH_PRE)) == 0) ||
+            (memcmp(buffer, TRANSACTION_OUTPUT_SCRIPT_P2WSH_PRE,
+                       sizeof(TRANSACTION_OUTPUT_SCRIPT_P2WSH_PRE)) == 0)) {
+            return 1;
+        }
+    }
+    if ((memcmp(buffer, TRANSACTION_OUTPUT_SCRIPT_PRE,
+                       sizeof(TRANSACTION_OUTPUT_SCRIPT_PRE)) == 0) &&
+        (memcmp(buffer + sizeof(TRANSACTION_OUTPUT_SCRIPT_PRE) + 20,
+                       TRANSACTION_OUTPUT_SCRIPT_POST,
+                       sizeof(TRANSACTION_OUTPUT_SCRIPT_POST)) == 0)) {
+        return 1;
+    }
+    if (COIN_KIND == COIN_KIND_HORIZEN) {
+        if ((memcmp(buffer, ZEN_OUTPUT_SCRIPT_PRE,
+                       sizeof(ZEN_OUTPUT_SCRIPT_PRE)) == 0) &&
+            (memcmp(buffer + sizeof(ZEN_OUTPUT_SCRIPT_PRE) + 20,
+                       ZEN_OUTPUT_SCRIPT_POST,
+                       sizeof(ZEN_OUTPUT_SCRIPT_POST)) == 0)) {
+            return 1;
+        }
+    }
+
+    return 0;
+}
+
+WEAK unsigned char output_script_is_p2sh(unsigned char *buffer) {
+    if ((memcmp(buffer, TRANSACTION_OUTPUT_SCRIPT_P2SH_PRE,
+                    sizeof(TRANSACTION_OUTPUT_SCRIPT_P2SH_PRE)) == 0) &&
+        (memcmp(buffer + sizeof(TRANSACTION_OUTPUT_SCRIPT_P2SH_PRE) + 20,
+                    TRANSACTION_OUTPUT_SCRIPT_P2SH_POST,
+                    sizeof(TRANSACTION_OUTPUT_SCRIPT_P2SH_POST)) == 0)) {
+        return 1;
+    }
+    if (COIN_KIND == COIN_KIND_HORIZEN) {
+        if ((memcmp(buffer, ZEN_TRANSACTION_OUTPUT_SCRIPT_P2SH_PRE,
+                       sizeof(ZEN_TRANSACTION_OUTPUT_SCRIPT_P2SH_PRE)) == 0) &&
+            (memcmp(buffer + sizeof(ZEN_TRANSACTION_OUTPUT_SCRIPT_P2SH_PRE) + 20,
+                       ZEN_TRANSACTION_OUTPUT_SCRIPT_P2SH_POST,
+                       sizeof(ZEN_TRANSACTION_OUTPUT_SCRIPT_P2SH_POST)) == 0)) {
+            return 1;
+        }
+    }
+    return 0;
+}
+
+WEAK unsigned char output_script_is_native_witness(unsigned char *buffer) {
+    if (COIN_NATIVE_SEGWIT_PREFIX) {
+        if ((memcmp(buffer, TRANSACTION_OUTPUT_SCRIPT_P2WPKH_PRE,
+                       sizeof(TRANSACTION_OUTPUT_SCRIPT_P2WPKH_PRE)) == 0) ||
+            (memcmp(buffer, TRANSACTION_OUTPUT_SCRIPT_P2WSH_PRE,
+                       sizeof(TRANSACTION_OUTPUT_SCRIPT_P2WSH_PRE)) == 0)) {
+            return 1;
+        }
+    }
+    return 0;
+}
+
+WEAK unsigned char output_script_is_op_return(unsigned char *buffer) {
+    if (COIN_KIND == COIN_KIND_BITCOIN_CASH) {
+        return ((buffer[1] == 0x6A) || ((buffer[1] == 0x00) && (buffer[2] == 0x6A)));
+    }
+    else {
+        return (buffer[1] == 0x6A);
+    }
+}
+
+WEAK unsigned char output_script_is_op_create_or_call(unsigned char *buffer,
+                                                        size_t size,
+                                                        unsigned char value) {
+    return (!output_script_is_regular(buffer) &&
+            !output_script_is_p2sh(buffer) &&
+            !output_script_is_op_return(buffer) && (buffer[0] <= 0xEA) &&
+            (buffer[0] < size) &&
+            (buffer[buffer[0]] == value));
+}
+
+WEAK unsigned char output_script_is_op_create(unsigned char *buffer,
+                                                size_t size) {
+    return output_script_is_op_create_or_call(buffer, size, 0xC1);
+}
+
+WEAK unsigned char output_script_is_op_call(unsigned char *buffer,
+                                              size_t size) {
+    return output_script_is_op_create_or_call(buffer, size, 0xC2);
+}
+
diff --git a/include/bcd.h b/lib-app-bitcoin/customizable_helpers.h
similarity index 58%
rename from include/bcd.h
rename to lib-app-bitcoin/customizable_helpers.h
index 42eb41ff..ab7ac1c9 100644
--- a/include/bcd.h
+++ b/lib-app-bitcoin/customizable_helpers.h
@@ -15,14 +15,17 @@
 *  limitations under the License.
 ********************************************************************************/
 
-#ifndef BCD_H
+#pragma once
 
-#define BCD_H
+#include "os.h"
+#include "cx.h"
 
-unsigned char
-convert_hex_amount_to_displayable_no_globals(unsigned char *amount, unsigned int config_flag, unsigned char* out);
+unsigned char output_script_is_regular(unsigned char *buffer);
+unsigned char output_script_is_p2sh(unsigned char *buffer);
+unsigned char output_script_is_op_return(unsigned char *buffer);
+unsigned char output_script_is_native_witness(unsigned char *buffer);
+unsigned char output_script_is_op_create(unsigned char *buffer,
+                                                size_t size);
+unsigned char output_script_is_op_call(unsigned char *buffer,
+                                                size_t size);
 
-unsigned char
-convert_hex_amount_to_displayable(unsigned char *amount);
-
-#endif
diff --git a/lib-app-bitcoin/customizable_ui.c b/lib-app-bitcoin/customizable_ui.c
new file mode 100644
index 00000000..fe81b443
--- /dev/null
+++ b/lib-app-bitcoin/customizable_ui.c
@@ -0,0 +1,117 @@
+/*******************************************************************************
+*   Ledger App - Bitcoin Wallet
+*   (c) 2016-2019 Ledger
+*
+*  Licensed under the Apache License, Version 2.0 (the "License");
+*  you may not use this file except in compliance with the License.
+*  You may obtain a copy of the License at
+*
+*      http://www.apache.org/licenses/LICENSE-2.0
+*
+*  Unless required by applicable law or agreed to in writing, software
+*  distributed under the License is distributed on an "AS IS" BASIS,
+*  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+*  See the License for the specific language governing permissions and
+*  limitations under the License.
+********************************************************************************/
+#include "customizable_ui.h"
+#include "customizable_helpers.h"
+#include "helpers.h"
+#include "context.h"
+#include "display_variables.h"
+#include "segwit_addr.h"
+#include "cashaddr.h"
+#include "be_operations.h"
+#include "display_utils.h"
+#include "read.h"
+
+
+WEAK void get_address_from_output_script(unsigned char* script, int script_size, char* out, int out_size) {
+    if (output_script_is_op_return(script)) {
+        strncpy(out, "OP_RETURN", out_size);
+        return;
+    }
+    if ((COIN_KIND == COIN_KIND_HYDRA) &&
+        output_script_is_op_create(script, script_size)) {
+        strncpy(out, "OP_CREATE", out_size);
+        return;
+    }
+    if ((COIN_KIND == COIN_KIND_HYDRA) &&
+        output_script_is_op_call(script, script_size)) {
+        strncpy(out, "OP_CALL", out_size);
+        return;
+    }
+    if (output_script_is_native_witness(script)) {
+        if (COIN_NATIVE_SEGWIT_PREFIX) {
+            segwit_addr_encode(
+                out, (char *)PIC(COIN_NATIVE_SEGWIT_PREFIX), 0,
+                script + OUTPUT_SCRIPT_NATIVE_WITNESS_PROGRAM_OFFSET,
+                script[OUTPUT_SCRIPT_NATIVE_WITNESS_PROGRAM_OFFSET - 1]);
+        }
+        return;
+    }
+    unsigned char versionSize;
+    unsigned char address[22];
+    unsigned short textSize;
+    int addressOffset = 3;
+    unsigned short version = COIN_P2SH_VERSION;
+
+    if (output_script_is_regular(script)) {
+        addressOffset = 4;
+        version = COIN_P2PKH_VERSION;
+    }
+
+    if (version > 255) {
+        versionSize = 2;
+        address[0] = (version >> 8);
+        address[1] = version;
+    } else {
+        versionSize = 1;
+        address[0] = version;
+    }
+    memmove(address + versionSize, script + addressOffset, 20);
+
+    // Prepare address
+    if (context_D.usingCashAddr) {
+        cashaddr_encode(
+            address + versionSize, 20, (uint8_t *)out, out_size,
+            (version == COIN_P2SH_VERSION
+                    ? CASHADDR_P2SH
+                    : CASHADDR_P2PKH));
+    } else {
+        textSize = public_key_to_encoded_base58(
+            address, 20 + versionSize, (unsigned char *)out,
+            out_size, version, 1);
+        out[textSize] = '\0';
+    }
+}
+
+WEAK uint8_t prepare_fees(void) {
+    if (context_D.transactionContext.relaxed) {
+        memmove(vars.tmp.feesAmount, "UNKNOWN", 7);
+        vars.tmp.feesAmount[7] = '\0';
+    } else {
+        unsigned char fees[8];
+        unsigned char borrow;
+
+        borrow = transaction_amount_sub_be(
+                fees, context_D.transactionContext.transactionAmount,
+                context_D.totalOutputAmount);
+        if (borrow && COIN_KIND == COIN_KIND_KOMODO) {
+            memmove(vars.tmp.feesAmount, "REWARD", 6);
+            vars.tmp.feesAmount[6] = '\0';
+        }
+        else {
+            if (borrow) {
+                PRINTF("Error : Fees not consistent");
+                goto error;
+            }
+        format_sats_amount(COIN_COINID_SHORT,
+                (uint64_t)read_u64_be(fees, 0), // Cast prevents weird compilo bug
+                vars.tmp.feesAmount);
+        }
+    }
+    return 1;
+error:
+    return 0;
+}
diff --git a/include/ecc.h b/lib-app-bitcoin/customizable_ui.h
similarity index 82%
rename from include/ecc.h
rename to lib-app-bitcoin/customizable_ui.h
index 4a07074d..75649c2b 100644
--- a/include/ecc.h
+++ b/lib-app-bitcoin/customizable_ui.h
@@ -14,13 +14,10 @@
 *  See the License for the specific language governing permissions and
 *  limitations under the License.
 ********************************************************************************/
-
-#ifndef ECC_H
-
-#define ECC_H
-
+#pragma once 
 #include "os.h"
+#include "macros.h"
 
-void compress_public_key_value(unsigned char *value);
+void get_address_from_output_script(unsigned char* script, int script_size, char* out, int out_size);
 
-#endif
+uint8_t prepare_fees(void);
diff --git a/lib-app-bitcoin/display_utils.c b/lib-app-bitcoin/display_utils.c
new file mode 100644
index 00000000..4bfae3f5
--- /dev/null
+++ b/lib-app-bitcoin/display_utils.c
@@ -0,0 +1,132 @@
+#include <stdbool.h>
+#include <stdio.h>
+#include <string.h>
+#include "ledger_assert.h"
+#include "read.h"
+#include "filesystem_tx.h"
+
+#include "./display_utils.h"
+
+// Division and modulus operators over uint64_t causes the inclusion of the __udivmoddi4 and other
+// library functions that occupy more than 400 bytes. Since performance is not critical and division
+// by 10 is sufficient, we avoid it with a binary search instead.
+static uint64_t div10(uint64_t n) {
+    if (n < 10) return 0;  // special case needed to make sure that n - 10 is safe
+
+    // Since low, mid and high are always <= UINT64_MAX / 10, there is no risk of overflow
+    uint64_t low = 0;
+    uint64_t high = UINT64_MAX / 10;
+
+    while (true) {
+        uint64_t mid = (low + high) / 2;
+
+        // the result equals mid if and only if mid * 10 <= n < mid * 10 + 10
+        // care is taken to make sure overflows and underflows are impossible
+        if (mid * 10 > n - 10 && n >= mid * 10) {
+            return mid;
+        } else if (n < mid * 10) {
+            high = mid - 1;
+        } else /* n >= 10 * mid + 10 */ {
+            low = mid + 1;
+        }
+    }
+}
+
+static uint64_t div100000000(uint64_t n) {
+    uint64_t res = n;
+    for (int i = 0; i < 8; i++) res = div10(res);
+    return res;
+}
+
+static size_t n_digits(uint64_t number) {
+    size_t count = 0;
+    do {
+        count++;
+
+        // HACK: avoid __udivmoddi4
+        // number /= 10;
+
+        number = div10(number);
+    } while (number != 0);
+    return count;
+}
+
+void format_sats_amount(const char *coin_name,
+                        uint64_t amount,
+                        char out[static MAX_AMOUNT_LENGTH + 1]) {
+    size_t coin_name_len = strlen(coin_name);
+    strncpy(out, coin_name, MAX_AMOUNT_LENGTH + 1);
+    out[coin_name_len] = ' ';
+
+    char *amount_str = out + coin_name_len + 1;
+
+    // HACK: avoid __udivmoddi4
+    // uint64_t integral_part = amount / 100000000;
+    // uint32_t fractional_part = (uint32_t) (amount % 100000000);
+    uint64_t integral_part = div100000000(amount);
+    uint32_t fractional_part = (uint32_t) (amount - integral_part * 100000000);
+
+    // format the integral part, starting from the least significant digit
+    size_t integral_part_digit_count = n_digits(integral_part);
+    for (unsigned int i = 0; i < integral_part_digit_count; i++) {
+        // HACK: avoid __udivmoddi4
+        // amount_str[integral_part_digit_count - 1 - i] = '0' + (integral_part % 10);
+        // integral_part /= 10;
+
+        uint64_t tmp_quotient = div10(integral_part);
+        char tmp_remainder = (char) (integral_part - 10 * tmp_quotient);
+        amount_str[integral_part_digit_count - 1 - i] = '0' + tmp_remainder;
+        integral_part = tmp_quotient;
+    }
+
+    if (fractional_part == 0) {
+        amount_str[integral_part_digit_count] = '\0';
+    } else {
+        // format the fractional part (exactly 8 digits, possibly with trailing zeros)
+        amount_str[integral_part_digit_count] = '.';
+        char *fract_part_str = amount_str + integral_part_digit_count + 1;
+        snprintf(fract_part_str, 8 + 1, "%08u", fractional_part);
+
+        // drop trailing zeros
+        for (int i = 7; i > 0 && fract_part_str[i] == '0'; i--) {
+            fract_part_str[i] = '\0';
+        }
+    }
+}
+
+unsigned char format_path(const unsigned char *bip32Path, char* out, unsigned char max_out_len) {
+
+    unsigned char bip32PathLength;
+    unsigned char i, offset;
+    unsigned int current_level;
+    bool hardened;
+
+    bip32PathLength = bip32Path[0];
+
+    LEDGER_ASSERT(bip32PathLength <= MAX_BIP32_PATH, "Wrong path len: %d", bip32PathLength);
+
+    bip32Path++;
+    out[0] = ' ';
+    offset=1;
+    for (i = 0; i < bip32PathLength; i++) {
+        current_level = read_u32_be(bip32Path, 0);
+        hardened = (bool)(current_level & 0x80000000);
+        if(hardened) {
+            //remove hardening flag
+            current_level ^= 0x80000000;
+        }
+        bip32Path += 4;
+        snprintf(out+offset, max_out_len-offset, "%u", current_level);
+        offset = strnlen(out, max_out_len);
+        LEDGER_ASSERT(offset < max_out_len - 2, "OVERFLOW");
+        if(hardened) out[offset++] = '\'';
+
+        out[offset++] = '/';
+        out[offset] = '\0';
+    }
+    // remove last '/'
+    out[offset-1] = '\0';
+
+    return offset -1;
+}
+
diff --git a/lib-app-bitcoin/display_utils.h b/lib-app-bitcoin/display_utils.h
new file mode 100644
index 00000000..f5f28ba7
--- /dev/null
+++ b/lib-app-bitcoin/display_utils.h
@@ -0,0 +1,24 @@
+#pragma once
+
+#include <stdint.h>
+
+// up to 5 chars for ticker, 1 space, up to 20 digits (20 = digits of 2^64), + 1 decimal separator
+#define MAX_AMOUNT_LENGTH (5 + 1 + 20 + 1)
+
+/**
+ * Converts a 64-bits unsigned integer into a decimal rapresentation, where the `amount` is a
+ * multiple of 1/100_000_000th. Trailing decimal zeros are not appended (and no decimal point is
+ * present if the `amount` is a multiple of 100_000_000). The resulting string is prefixed with a
+ * ticker name (up to 5 characters long), followed by a space.
+ *
+ * @param coin_name a zero-terminated ticker name, at most 5 characterso long (not including the
+ * terminating 0)
+ * @param amount the amount to format
+ * @param out the output array which must be at least MAX_AMOUNT_LENGTH + 1 bytes long
+ */
+void format_sats_amount(const char *coin_name,
+                        uint64_t amount,
+                        char out[static MAX_AMOUNT_LENGTH + 1]);
+
+unsigned char format_path(const unsigned char *bip32Path, char* out, unsigned char max_out_len);
+
diff --git a/src/display_variables.c b/lib-app-bitcoin/display_variables.c
similarity index 100%
rename from src/display_variables.c
rename to lib-app-bitcoin/display_variables.c
diff --git a/src/public_ram_variables.h b/lib-app-bitcoin/filesystem.h
similarity index 65%
rename from src/public_ram_variables.h
rename to lib-app-bitcoin/filesystem.h
index 3251c5da..2dcf16f2 100644
--- a/src/public_ram_variables.h
+++ b/lib-app-bitcoin/filesystem.h
@@ -15,14 +15,26 @@
 *  limitations under the License.
 ********************************************************************************/
 
-#ifndef _PUBLIC_RAM_VARIABLES_H_
-#define _PUBLIC_RAM_VARIABLES_H_
+#pragma once 
 
-#include "config.h"
-
-#include "secure_value.h"
+#include "os.h"
 #include "context.h"
+#include "filesystem_tx.h"
+
+enum family_e {
+    FAMILY_BITCOIN = 0x01,
+    FAMILY_PEERCOIN = 0x02,
+    FAMILY_STEALTH = 0x04
+};
+
+typedef struct backup_area_s {
+    uint8_t trustedinput_key[32];
+} backup_area_t;
 
-extern context_t context_D;
+typedef struct storage_s {
+    backup_area_t bkp;
+} storage_t;
 
-#endif /* _PUBLIC_RAM_VARIABLES_H_ */
+// the global nvram memory variable
+extern storage_t const N_real;
+#define N_btchip (*(volatile storage_t *)PIC(&N_real))
diff --git a/include/filesystem_tx.h b/lib-app-bitcoin/filesystem_tx.h
similarity index 100%
rename from include/filesystem_tx.h
rename to lib-app-bitcoin/filesystem_tx.h
diff --git a/src/apdu_get_coin_version.c b/lib-app-bitcoin/handler/get_coin_version.c
similarity index 78%
rename from src/apdu_get_coin_version.c
rename to lib-app-bitcoin/handler/get_coin_version.c
index 97e0ac72..e47f939c 100644
--- a/src/apdu_get_coin_version.c
+++ b/lib-app-bitcoin/handler/get_coin_version.c
@@ -15,19 +15,21 @@
 *  limitations under the License.
 ********************************************************************************/
 
-#include "internal.h"
-#include "apdu_constants.h"
+#include "io.h"
+#include "write.h"
 
-#define P1_VERSION_ONLY 0x00
-#define P1_VERSION_COINID 0x01
+#include "context.h"
+#include "apdu_constants.h"
 
-unsigned short apdu_get_coin_version() {
+WEAK unsigned short handler_get_coin_version(void) {
     uint8_t offset = 0;
 
-    G_io_apdu_buffer[offset++] = COIN_P2PKH_VERSION >> 8;
-    G_io_apdu_buffer[offset++] = COIN_P2PKH_VERSION;
-    G_io_apdu_buffer[offset++] = COIN_P2SH_VERSION >> 8;
-    G_io_apdu_buffer[offset++] = COIN_P2SH_VERSION;
+    write_u16_be(G_io_apdu_buffer, offset, COIN_P2PKH_VERSION);
+    offset += 2;
+
+    write_u16_be(G_io_apdu_buffer, offset, COIN_P2SH_VERSION);
+    offset += 2;
+
     G_io_apdu_buffer[offset++] = COIN_FAMILY;
     G_io_apdu_buffer[offset++] = strlen(COIN_COINID);
     memmove(G_io_apdu_buffer + offset, COIN_COINID,
@@ -39,5 +41,5 @@ unsigned short apdu_get_coin_version() {
     offset += strlen(COIN_COINID_SHORT);
     context_D.outLength = offset;
 
-    return SW_OK;
+    return io_send_response_pointer(G_io_apdu_buffer, context_D.outLength, SW_OK);
 }
diff --git a/src/apdu_get_firmware_version.c b/lib-app-bitcoin/handler/get_firmware_version.c
similarity index 54%
rename from src/apdu_get_firmware_version.c
rename to lib-app-bitcoin/handler/get_firmware_version.c
index b2b90954..d3f100d1 100644
--- a/src/apdu_get_firmware_version.c
+++ b/lib-app-bitcoin/handler/get_firmware_version.c
@@ -14,52 +14,37 @@
 *  See the License for the specific language governing permissions and
 *  limitations under the License.
 ********************************************************************************/
+#include "io.h"
 
-#include "internal.h"
+#include "context.h"
 #include "apdu_constants.h"
 
-#define FEATURES_COMPRESSED_KEYS 0x01
 #define FEATURES_SELF_SCREEN_BUTTONS 0x02
-#define FEATURES_EXTERNAL_SCREEN_BUTTONS 0x04
 #define FEATURES_NFC 0x08
 #define FEATURES_BLE 0x10
-#define FEATURES_TEE 0x20
 
 #define MODE_SETUP 0x01
 #define MODE_OPERATION 0x02
 
+#define FEATURES (FEATURES_NFC | FEATURES_BLE | FEATURES_SELF_SCREEN_BUTTONS)
+#define MODE (MODE_SETUP | MODE_OPERATION)
+
 #define ARCH_ID 0x30
 
-// Java Card is 0x60
 #define TCS_LOADER_PATCH_VERSION 0
 
-void get_firmware_version(unsigned char *buffer) {
-    buffer[0] = ARCH_ID;
-    buffer[1] = MAJOR_VERSION;
-    buffer[2] = MINOR_VERSION;
-    buffer[3] = PATCH_VERSION;
-    buffer[4] = 1;
-    buffer[5] = TCS_LOADER_PATCH_VERSION;
-}
-
-unsigned short apdu_get_firmware_version() {
-    G_io_apdu_buffer[0] =
-        (((N_btchip.bkp.config.options & OPTION_UNCOMPRESSED_KEYS) != 0)
-             ? 0x00
-             : 0x01);
-
-    G_io_apdu_buffer[0] |= FEATURES_NFC;
-    G_io_apdu_buffer[0] |= FEATURES_BLE;
-
-    G_io_apdu_buffer[0] |= FEATURES_SELF_SCREEN_BUTTONS;
-
-    get_firmware_version(G_io_apdu_buffer + 1);
+WEAK unsigned short handler_get_firmware_version() {
 
-    G_io_apdu_buffer[7] = 0x00;
-    G_io_apdu_buffer[7] |= MODE_SETUP;
-    G_io_apdu_buffer[7] |= MODE_OPERATION;
+    G_io_apdu_buffer[0] = FEATURES;
+    G_io_apdu_buffer[1] = ARCH_ID;
+    G_io_apdu_buffer[2] = MAJOR_VERSION;
+    G_io_apdu_buffer[3] = MINOR_VERSION;
+    G_io_apdu_buffer[4] = PATCH_VERSION;
+    G_io_apdu_buffer[5] = 1;
+    G_io_apdu_buffer[6] = TCS_LOADER_PATCH_VERSION;
+    G_io_apdu_buffer[7] = MODE;
 
     context_D.outLength = 0x08;
 
-    return SW_OK;
+    return io_send_response_pointer(G_io_apdu_buffer, context_D.outLength, SW_OK);
 }
diff --git a/src/apdu_get_trusted_input.c b/lib-app-bitcoin/handler/get_trusted_input.c
similarity index 77%
rename from src/apdu_get_trusted_input.c
rename to lib-app-bitcoin/handler/get_trusted_input.c
index 48fa119a..6c07bb96 100644
--- a/src/apdu_get_trusted_input.c
+++ b/lib-app-bitcoin/handler/get_trusted_input.c
@@ -14,24 +14,25 @@
 *  See the License for the specific language governing permissions and
 *  limitations under the License.
 ********************************************************************************/
-
-#include "internal.h"
-#include "apdu_constants.h"
 #include "lib_standard_app/read.h"
 #include "lib_standard_app/write.h"
+#include "io.h"
+
+#include "context.h"
+#include "filesystem.h"
+#include "transaction.h"
+#include "apdu_constants.h"
 
 #define GET_TRUSTED_INPUT_P1_FIRST 0x00
 #define GET_TRUSTED_INPUT_P1_NEXT 0x80
 
-unsigned short apdu_get_trusted_input() {
-    unsigned char apduLength;
+WEAK unsigned short handler_get_trusted_input(buffer_t* buffer, uint8_t p1, uint8_t p2) {
     unsigned char dataOffset = 0;
-    apduLength = G_io_apdu_buffer[ISO_OFFSET_LC];
 
-    if (G_io_apdu_buffer[ISO_OFFSET_P1] == GET_TRUSTED_INPUT_P1_FIRST) {
+    if (p1 == GET_TRUSTED_INPUT_P1_FIRST) {
         // Initialize
         context_D.transactionTargetInput =
-            read_u32_be(G_io_apdu_buffer, ISO_OFFSET_CDATA);
+            read_u32_be(buffer->ptr, 0);
         context_D.transactionContext.transactionState =
             TRANSACTION_NONE;
         context_D.trustedInputProcessed = 0;
@@ -40,16 +41,16 @@ unsigned short apdu_get_trusted_input() {
         context_D.transactionHashOption = TRANSACTION_HASH_FULL;
         context_D.usingSegwit = 0;
         context_D.usingOverwinter = 0;
-    } else if (G_io_apdu_buffer[ISO_OFFSET_P1] != GET_TRUSTED_INPUT_P1_NEXT) {
-        return SW_INCORRECT_P1_P2;
+    } else if (p1 != GET_TRUSTED_INPUT_P1_NEXT) {
+        return io_send_sw(SW_INCORRECT_P1_P2);
     }
 
-    if (G_io_apdu_buffer[ISO_OFFSET_P2] != 0x00) {
-        return SW_INCORRECT_P1_P2;
+    if (p2 != 0x00) {
+        return io_send_sw(SW_INCORRECT_P1_P2);
     }
-    context_D.transactionBufferPointer =
-        G_io_apdu_buffer + ISO_OFFSET_CDATA + dataOffset;
-    context_D.transactionDataRemaining = apduLength - dataOffset;
+
+    context_D.transactionBufferPointer = (uint8_t* ) buffer->ptr + dataOffset;
+    context_D.transactionDataRemaining = buffer->size - dataOffset;
 
     transaction_parse(PARSE_MODE_TRUSTED_INPUT);
 
@@ -60,12 +61,12 @@ unsigned short apdu_get_trusted_input() {
             TRANSACTION_NONE;
         if (!context_D.trustedInputProcessed) {
             // Output was not found
-            return SW_INCORRECT_DATA;
+            return io_send_sw(SW_INCORRECT_DATA);
         }
 
         if (cx_hash_no_throw(&context_D.transactionHashFull.sha256.header, CX_LAST,
                 NULL, 0, G_io_apdu_buffer + TRUSTED_INPUT_SIZE, 32)) {
-            return SW_TECHNICAL_PROBLEM;
+            return io_send_sw(SW_TECHNICAL_PROBLEM);
         }
 
         // Otherwise prepare
@@ -84,5 +85,5 @@ unsigned short apdu_get_trusted_input() {
                        TRUSTED_INPUT_SIZE, G_io_apdu_buffer + TRUSTED_INPUT_SIZE, 32);
         context_D.outLength = TRUSTED_INPUT_TOTAL_SIZE;
     }
-    return SW_OK;
+    return io_send_response_pointer(G_io_apdu_buffer, context_D.outLength, SW_OK);
 }
diff --git a/src/apdu_get_wallet_public_key.c b/lib-app-bitcoin/handler/get_wallet_public_key.c
similarity index 64%
rename from src/apdu_get_wallet_public_key.c
rename to lib-app-bitcoin/handler/get_wallet_public_key.c
index 53baced4..da1c32ba 100644
--- a/src/apdu_get_wallet_public_key.c
+++ b/lib-app-bitcoin/handler/get_wallet_public_key.c
@@ -15,18 +15,28 @@
 *  limitations under the License.
 ********************************************************************************/
 
-#include "internal.h"
+#include "context.h"
+#include "helpers.h"
 #include "apdu_constants.h"
 
-#include "bagl_extensions.h"
+#include "extensions.h"
 
 #include "segwit_addr.h"
 #include "cashaddr.h"
-#include "apdu_get_wallet_public_key.h"
 #include "lib_standard_app/read.h"
 #include "swap.h"
+#include "io.h"
 
-int get_public_key_chain_code(unsigned char* keyPath, size_t keyPath_len, unsigned char* publicKey, unsigned char* chainCode) {
+#define P1_NO_DISPLAY 0x00
+#define P1_DISPLAY 0x01
+#define P1_REQUEST_TOKEN 0x02
+
+#define P2_LEGACY 0x00
+#define P2_SEGWIT 0x01
+#define P2_NATIVE_SEGWIT 0x02
+#define P2_CASHADDR 0x03
+
+static int get_public_key_chain_code(const unsigned char* keyPath, size_t keyPath_len, unsigned char* publicKey, unsigned char* chainCode) {
     uint8_t public_key[65];
     int keyLength = 0;
 
@@ -42,59 +52,57 @@ int get_public_key_chain_code(unsigned char* keyPath, size_t keyPath_len, unsign
     return keyLength;
 }
 
-unsigned short apdu_get_wallet_public_key() {
+WEAK unsigned short handler_get_wallet_public_key(buffer_t* buffer, uint8_t p1, uint8_t p2) {
     unsigned char keyLength;
     unsigned char chainCode[32];
     uint8_t is_derivation_path_unusual = 0;
 
-    bool display = (G_io_apdu_buffer[ISO_OFFSET_P1] == P1_DISPLAY);
-    bool segwit = (G_io_apdu_buffer[ISO_OFFSET_P2] == P2_SEGWIT);
-    bool nativeSegwit = (G_io_apdu_buffer[ISO_OFFSET_P2] == P2_NATIVE_SEGWIT);
-    bool cashAddr = (G_io_apdu_buffer[ISO_OFFSET_P2] == P2_CASHADDR);
+    bool display = (p1 == P1_DISPLAY);
+    bool segwit = (p2 == P2_SEGWIT);
+    bool nativeSegwit = (p2 == P2_NATIVE_SEGWIT);
+    bool cashAddr = (p2 == P2_CASHADDR);
+
     if (display && G_called_from_swap) {
-        return SW_INCORRECT_DATA;
+        PRINTF("Refused INS when in SWAP mode\n");
+        return io_send_sw(SW_INS_NOT_SUPPORTED);
     }
-    switch (G_io_apdu_buffer[ISO_OFFSET_P1]) {
-    case P1_NO_DISPLAY:
-    case P1_DISPLAY:
-    case P1_REQUEST_TOKEN:
-        break;
-    default:
-        return SW_INCORRECT_P1_P2;
+
+    if (p1 != P1_NO_DISPLAY && p1 != P1_DISPLAY) {
+        PRINTF("Wrong P1 value\n");
+        return io_send_sw(SW_INCORRECT_P1_P2);
     }
 
-    switch (G_io_apdu_buffer[ISO_OFFSET_P2]) {
-    case P2_NATIVE_SEGWIT:
-        if (!(COIN_NATIVE_SEGWIT_PREFIX)) {
-            return SW_INCORRECT_P1_P2;
-        }
-        __attribute__((fallthrough));
-    case P2_LEGACY:
-    case P2_SEGWIT:
-        break;
-    case P2_CASHADDR:
-        if (COIN_KIND != COIN_KIND_BITCOIN_CASH) {
-            return SW_INCORRECT_P1_P2;
-        }
-        break;
-    default:
-        return SW_INCORRECT_P1_P2;
+    if (p2 == P2_NATIVE_SEGWIT && !COIN_NATIVE_SEGWIT_PREFIX) {
+        PRINTF("Wrong P2 value\n");
+        return io_send_sw(SW_INCORRECT_P1_P2);
     }
 
-    if (G_io_apdu_buffer[ISO_OFFSET_LC] < 0x01) {
-        return SW_INCORRECT_LENGTH;
+    if (p2 == P2_CASHADDR && COIN_KIND != COIN_KIND_BITCOIN_CASH) {
+        PRINTF("Wrong P2 value\n");
+        return io_send_sw(SW_INCORRECT_P1_P2);
     }
+
+    if (p2 != P2_NATIVE_SEGWIT && p2 != P2_LEGACY && p2 != P2_SEGWIT && p2 != P2_CASHADDR) {
+        PRINTF("Wrong P2 value\n");
+        return io_send_sw(SW_INCORRECT_P1_P2);
+    }
+
+    if (buffer->size < 0x01) {
+        PRINTF("Wrong size\n");
+        return io_send_sw(SW_INCORRECT_LENGTH);
+    }
+
     if (display) {
-        is_derivation_path_unusual = set_key_path_to_display(G_io_apdu_buffer + ISO_OFFSET_CDATA);
+        is_derivation_path_unusual = set_key_path_to_display(buffer->ptr);
     }
 
-    unsigned char bip44_enforced = enforce_bip44_coin_type(G_io_apdu_buffer + ISO_OFFSET_CDATA, true);
+    unsigned char bip44_enforced = enforce_bip44_coin_type(buffer->ptr, true);
 
     G_io_apdu_buffer[0] = 65;
-    keyLength = get_public_key_chain_code(G_io_apdu_buffer + ISO_OFFSET_CDATA, MAX_BIP32_PATH_LENGTH, G_io_apdu_buffer + 1, chainCode);
+    keyLength = get_public_key_chain_code(buffer->ptr, MAX_BIP32_PATH_LENGTH, G_io_apdu_buffer + 1, chainCode);
 
     if (keyLength == 0) {
-        return SW_TECHNICAL_PROBLEM;
+        return io_send_sw(SW_TECHNICAL_PROBLEM);
     }
 
     if (cashAddr) {
@@ -155,31 +163,24 @@ unsigned short apdu_get_wallet_public_key() {
 
     if (display) {
         if (keyLength > 50) {
-            return SW_INCORRECT_DATA;
+            return io_send_sw(SW_INCORRECT_DATA);
         }
         // Hax, avoid wasting space
         memmove(G_io_apdu_buffer + 200, G_io_apdu_buffer + 67, keyLength);
         G_io_apdu_buffer[200 + keyLength] = '\0';
-        context_D.io_flags |= IO_ASYNCH_REPLY;
-        bagl_display_public_key(is_derivation_path_unusual);
+        display_public_key(is_derivation_path_unusual);
+        return 0;
     }
-
-    return SW_OK;
+    return io_send_response_pointer(G_io_apdu_buffer, context_D.outLength, SW_OK);
 }
 
-void bagl_user_action_display(unsigned char confirming) {
-    unsigned short sw = SW_OK;
+int user_action_display(unsigned char confirming) {
     // confirm and finish the apdu exchange //spaghetti
     if (confirming) {
-        context_D.outLength -=
-            2; // status was already set by the last call
+        return io_send_response_pointer(G_io_apdu_buffer, context_D.outLength, SW_OK);
 
     } else {
-        sw = SW_CONDITIONS_OF_USE_NOT_SATISFIED;
         context_D.outLength = 0;
+        return io_send_sw(SW_CONDITIONS_OF_USE_NOT_SATISFIED);
     }
-    G_io_apdu_buffer[context_D.outLength++] = sw >> 8;
-    G_io_apdu_buffer[context_D.outLength++] = sw;
-
-    io_exchange(CHANNEL_APDU | IO_RETURN_AFTER_TX, context_D.outLength);
 }
diff --git a/src/apdu_hash_input_finalize_full.c b/lib-app-bitcoin/handler/hash_input_finalize_full.c
similarity index 80%
rename from src/apdu_hash_input_finalize_full.c
rename to lib-app-bitcoin/handler/hash_input_finalize_full.c
index 3e69d334..a1ed5acd 100644
--- a/src/apdu_hash_input_finalize_full.c
+++ b/lib-app-bitcoin/handler/hash_input_finalize_full.c
@@ -18,13 +18,18 @@
 // TODO Trustlet, BAGL : process each output separately.
 // review nvm_write policy
 
-#include "internal.h"
+#include "crypto_helpers.h"
+#include "read.h"
+#include "swap.h"
+#include "io.h"
+
+#include "context.h"
+#include "helpers.h"
+#include "customizable_helpers.h"
 #include "apdu_constants.h"
-#include "bagl_extensions.h"
+#include "extensions.h"
 #include "ui.h"
-#include "lib_standard_app/crypto_helpers.h"
-#include "lib_standard_app/read.h"
-#include "swap.h"
+#include "be_operations.h"
 
 #define FINALIZE_P1_MORE 0x00
 #define FINALIZE_P1_LAST 0x80
@@ -35,7 +40,7 @@
 #define FLAG_SIGNATURE 0x01
 #define FLAG_CHANGE_VALIDATED 0x80
 
-void apdu_hash_input_finalize_full_reset(void) {
+void hash_input_finalize_full_reset(void) {
     context_D.currentOutputOffset = 0;
     context_D.outputParsingState = OUTPUT_PARSING_NUMBER_OUTPUTS;
     memset(context_D.totalOutputAmount, 0,
@@ -43,11 +48,10 @@ void apdu_hash_input_finalize_full_reset(void) {
     context_D.changeOutputFound = 0;
 }
 
-static bool check_output_displayable() {
-    bool displayable = true;
+static int check_output_displayable(bool* displayable) {
+    *displayable = true;
     unsigned char amount[8], isOpReturn, isP2sh, isNativeSegwit, j,
         nullAmount = 1;
-    unsigned char isOpCreate, isOpCall;
 
     for (j = 0; j < 8; j++) {
         if (context_D.currentOutput[j] != 0) {
@@ -65,10 +69,11 @@ static bool check_output_displayable() {
     isP2sh = output_script_is_p2sh(context_D.currentOutput + 8);
     isNativeSegwit = output_script_is_native_witness(
         context_D.currentOutput + 8);
-    isOpCreate =
+#ifndef __clang_analyzer__
+    unsigned char isOpCreate =
         output_script_is_op_create(context_D.currentOutput + 8,
           sizeof(context_D.currentOutput) - 8);
-    isOpCall =
+    unsigned char isOpCall =
         output_script_is_op_call(context_D.currentOutput + 8,
           sizeof(context_D.currentOutput) - 8);
     if (((COIN_KIND == COIN_KIND_HYDRA) &&
@@ -78,8 +83,9 @@ static bool check_output_displayable() {
          !output_script_is_regular(context_D.currentOutput + 8) &&
          !isP2sh && !(nullAmount && isOpReturn))) {
         PRINTF("Error : Unrecognized output script");
-        THROW(EXCEPTION);
+        return -1;
     }
+#endif
     if (context_D.tmpCtx.output.changeInitialized && !isOpReturn) {
         bool changeFound = false;
         unsigned char addressOffset =
@@ -105,27 +111,26 @@ static bool check_output_displayable() {
                 } else {
                     // Attempt to avoid fatal failures on Bitcoin Cash
                     PRINTF("Error : Non spendable Segwit change");
-                    THROW(EXCEPTION);
+                    return -1;
                 }
             }
         }
         if (changeFound) {
             if (context_D.changeOutputFound) {
                 PRINTF("Error : Multiple change output found");
-                THROW(EXCEPTION);
+                return -1;
             }
             context_D.changeOutputFound = true;
-            displayable = false;
+            *displayable = false;
         }
     }
-
-    return displayable;
+    return 0;
 }
 
-bool handle_output_state() {
+int handle_output_state(unsigned int* processed) {
     uint32_t discardSize = 0;
     context_D.discardSize = 0;
-    bool processed = false;
+    *processed = 0;
     switch (context_D.outputParsingState) {
     case OUTPUT_PARSING_NUMBER_OUTPUTS: {
         context_D.totalOutputs = 0;
@@ -137,7 +142,7 @@ bool handle_output_state() {
                 context_D.currentOutput[0];
             discardSize = 1;
             context_D.outputParsingState = OUTPUT_PARSING_OUTPUT;
-            processed = true;
+            *processed = 1;
             break;
         }
         if (context_D.currentOutput[0] == 0xFD) {
@@ -149,7 +154,7 @@ bool handle_output_state() {
                 context_D.currentOutput[1];
             discardSize = 3;
             context_D.outputParsingState = OUTPUT_PARSING_OUTPUT;
-            processed = true;
+            *processed = 1;
             break;
         } else if (context_D.currentOutput[0] == 0xFE) {
             if (context_D.currentOutputOffset < 5) {
@@ -159,15 +164,15 @@ bool handle_output_state() {
                 read_u32_le(context_D.currentOutput, 1);
             discardSize = 5;
             context_D.outputParsingState = OUTPUT_PARSING_OUTPUT;
-            processed = true;
+            *processed = 1;
             break;
         } else {
-            THROW(EXCEPTION);
+            return -1;
         }
     } break;
 
     case OUTPUT_PARSING_OUTPUT: {
-        unsigned int scriptSize;
+        unsigned int scriptSize = 0;
         if (context_D.currentOutputOffset < 9) {
             break;
         }
@@ -182,7 +187,7 @@ bool handle_output_state() {
             discardSize = 3;
         } else {
             // Unrealistically large script
-            THROW(EXCEPTION);
+            return -1;
         }
         if (context_D.currentOutputOffset <
             8 + discardSize + scriptSize) {
@@ -190,24 +195,28 @@ bool handle_output_state() {
             break;
         }
 
-        processed = true;
+        *processed = 1;
 
         discardSize += 8 + scriptSize;
 
-        if (check_output_displayable()) {
-            context_D.io_flags |= IO_ASYNCH_REPLY;
+        bool displayable;
+        if (check_output_displayable(&displayable)) {
+            return -1;
+        }
 
+        if (displayable) {
             // The output can be processed by the UI
 
             context_D.discardSize = discardSize;
             discardSize = 0;
+            *processed = 2;
         } else {
             context_D.remainingOutputs--;
         }
     } break;
 
     default:
-        THROW(EXCEPTION);
+        return -1;
     }
 
     if (discardSize != 0) {
@@ -217,38 +226,32 @@ bool handle_output_state() {
         context_D.currentOutputOffset -= discardSize;
     }
 
-    return processed;
+    return 0;
 }
 
 // out should be 32 bytes, even only 20 bytes is significant for output
 int get_pubkey_hash160(unsigned char* keyPath, size_t keyPath_len, unsigned char* out) {
     cx_ecfp_public_key_t public_key;
-    int keyLength;
     if (get_public_key(keyPath, keyPath_len, public_key.W, NULL)) {
         return -1;
     }
-
     compress_public_key_value(public_key.W);
-    keyLength = 33;
 
     public_key_hash160(
         public_key.W,   // IN
-        keyLength,      // INLEN
+        33,             // INLEN
         out             // OUT
     );
     return 0;
 }
 
-unsigned short apdu_hash_input_finalize_full_internal(
-    transaction_summary_t *transactionSummary) {
+static unsigned short hash_input_finalize_full_internal(transaction_summary_t *transactionSummary, buffer_t* buffer, uint8_t p1, uint8_t p2, bool *async) {
     unsigned char authorizationHash[32];
-    unsigned char apduLength;
     unsigned short sw = SW_OK;
     unsigned char *target = G_io_apdu_buffer;
-    unsigned char p1 = G_io_apdu_buffer[ISO_OFFSET_P1];
     unsigned char hashOffset = 0;
 
-    apduLength = G_io_apdu_buffer[ISO_OFFSET_LC];
+    (void) p2;
 
     if ((p1 != FINALIZE_P1_MORE) && (p1 != FINALIZE_P1_LAST) &&
         (p1 != FINALIZE_P1_CHANGEINFO)) {
@@ -258,7 +261,7 @@ unsigned short apdu_hash_input_finalize_full_internal(
     // See if there is a hashing offset
     if (context_D.usingSegwit &&
         (context_D.tmpCtx.output.multipleOutput == 0)) {
-        unsigned char firstByte = G_io_apdu_buffer[ISO_OFFSET_CDATA];
+        unsigned char firstByte = buffer->ptr[0];
         if (firstByte < 0xfd) {
             hashOffset = 1;
         } else if (firstByte == 0xfd) {
@@ -278,7 +281,6 @@ unsigned short apdu_hash_input_finalize_full_internal(
     if (p1 == FINALIZE_P1_CHANGEINFO) {
         if (!context_D.transactionContext.firstSigned) {
             // Already validated, should be prevented on the client side
-return_OK:
             return SW_OK;
         }
         if (!context_D.tmpCtx.output.changeAccepted) {
@@ -287,17 +289,17 @@ unsigned short apdu_hash_input_finalize_full_internal(
         }
         memset(transactionSummary, 0,
                 sizeof(transaction_summary_t));
-        if (G_io_apdu_buffer[ISO_OFFSET_CDATA] == 0x00) {
+        if (buffer->ptr[0] == 0x00) {
             // Called with no change path, abort, should be prevented on
             // the client side
-            goto return_OK;
+            return SW_OK;
         }
         memmove(transactionSummary->keyPath,
-                G_io_apdu_buffer + ISO_OFFSET_CDATA,
+                buffer->ptr,
                 MAX_BIP32_PATH_LENGTH);
 
         if (get_pubkey_hash160(transactionSummary->keyPath, sizeof(transactionSummary->keyPath), context_D.tmpCtx.output.changeAddress)) {
-            sw = SW_TECHNICAL_DETAILS(0x0F);
+            sw = SW_TECHNICAL_PROBLEM_2;
             goto discardTransaction;
         }
         PRINTF("Change address = %.*H\n", 20, context_D.tmpCtx.output.changeAddress);
@@ -312,41 +314,41 @@ unsigned short apdu_hash_input_finalize_full_internal(
                 sw = SW_CONDITIONS_OF_USE_NOT_SATISFIED;
                 goto discardTransaction;
             }
-            context_D.io_flags |= IO_ASYNCH_REPLY;
+            *async = true;
             context_D.outputParsingState = BIP44_CHANGE_PATH_VALIDATION;
-            bagl_request_change_path_approval(transactionSummary->keyPath);
+            request_change_path_approval(transactionSummary->keyPath);
         }
 
-        goto return_OK;
+        return SW_OK;
     }
 
     // Always update the transaction & authorization hashes with the
     // given data
     // For SegWit, this has been reset to hold hashOutputs
     if (!context_D.segwitParsedOnce) {
-        if ((int)(apduLength - hashOffset) < 0) {
+        if ((int)(buffer->size - hashOffset) < 0) {
             sw = SW_INCORRECT_DATA;
             goto discardTransaction;
         }
         if (context_D.usingOverwinter) {
-            if (cx_hash_no_throw(&context_D.transactionHashFull.blake2b.header, 0, G_io_apdu_buffer + ISO_OFFSET_CDATA + hashOffset, apduLength - hashOffset, NULL, 0)) {
-                sw = SW_TECHNICAL_DETAILS(0x0F);
+            if (cx_hash_no_throw(&context_D.transactionHashFull.blake2b.header, 0, buffer->ptr + hashOffset, buffer->size - hashOffset, NULL, 0)) {
+                sw = SW_TECHNICAL_PROBLEM_2;
                 goto discardTransaction;
             }
         }
         else {
-            PRINTF("--- ADD TO HASH FULL:\n%.*H\n", apduLength - hashOffset, G_io_apdu_buffer + ISO_OFFSET_CDATA + hashOffset);
+            PRINTF("--- ADD TO HASH FULL:\n%.*H\n", buffer->size - hashOffset, buffer->ptr + hashOffset);
             if (cx_hash_no_throw(&context_D.transactionHashFull.sha256.header, 0,
-                        G_io_apdu_buffer + ISO_OFFSET_CDATA + hashOffset,
-                        apduLength - hashOffset, NULL, 0)) {
-                sw = SW_TECHNICAL_DETAILS(0x0F);
+                        buffer->ptr + hashOffset,
+                        buffer->size - hashOffset, NULL, 0)) {
+                sw = SW_TECHNICAL_PROBLEM_2;
                 goto discardTransaction;
             }
         }
     }
 
     if (context_D.transactionContext.firstSigned) {
-        if ((context_D.currentOutputOffset + apduLength) >
+        if ((context_D.currentOutputOffset + buffer->size) >
                 sizeof(context_D.currentOutput)) {
             PRINTF("Output is too long to be checked\n");
             sw = SW_INCORRECT_DATA;
@@ -354,46 +356,53 @@ unsigned short apdu_hash_input_finalize_full_internal(
         }
         memmove(context_D.currentOutput +
                 context_D.currentOutputOffset,
-                G_io_apdu_buffer + ISO_OFFSET_CDATA, apduLength);
-        context_D.currentOutputOffset += apduLength;
+                buffer->ptr, buffer->size);
+        context_D.currentOutputOffset += buffer->size;
 
-        while (handle_output_state() &&
-                (!(context_D.io_flags & IO_ASYNCH_REPLY)))
-            ;
+        unsigned int processed = 1;
+        while (processed == 1) {
+            if (handle_output_state(&processed)) {
+                sw = SW_TECHNICAL_PROBLEM_2;
+                goto discardTransaction;
+            }
+        }
 
+        if (processed == 2) {
+            *async = true;
+        }
         // Finalize the TX if necessary
 
         if ((context_D.remainingOutputs == 0) &&
-                (!(context_D.io_flags & IO_ASYNCH_REPLY))) {
-            context_D.io_flags |= IO_ASYNCH_REPLY;
+                (!*async)) {
+            *async = true;
             context_D.outputParsingState =
                 OUTPUT_FINALIZE_TX;
         }
     }
 
-    if (G_io_apdu_buffer[ISO_OFFSET_P1] == FINALIZE_P1_MORE) {
+    if (p1 == FINALIZE_P1_MORE) {
         if (!context_D.usingSegwit) {
-            PRINTF("--- ADD TO HASH AUTH:\n%.*H\n", apduLength, G_io_apdu_buffer + ISO_OFFSET_CDATA);
+            PRINTF("--- ADD TO HASH AUTH:\n%.*H\n", buffer->size, buffer->ptr);
             if (cx_hash_no_throw(
                         &context_D.transactionHashAuthorization.header,
-                        0, G_io_apdu_buffer + ISO_OFFSET_CDATA, apduLength,
+                        0, buffer->ptr, buffer->size,
                         NULL, 0)) {
-                sw = SW_TECHNICAL_DETAILS(0x0F);
+                sw = SW_TECHNICAL_PROBLEM_2;
                 goto discardTransaction;
             }
         }
         G_io_apdu_buffer[0] = 0x00;
         context_D.outLength = 1;
         context_D.tmpCtx.output.multipleOutput = 1;
-        goto return_OK;
+        return SW_OK;
     }
 
     if (!context_D.usingSegwit) {
-        PRINTF("--- ADD TO HASH AUTH:\n%.*H\n", apduLength, G_io_apdu_buffer + ISO_OFFSET_CDATA);
+        PRINTF("--- ADD TO HASH AUTH:\n%.*H\n", buffer->size, buffer->ptr);
         if (cx_hash_no_throw(&context_D.transactionHashAuthorization.header,
-                    CX_LAST, G_io_apdu_buffer + ISO_OFFSET_CDATA,
-                    apduLength, authorizationHash, 32)) {
-            sw = SW_TECHNICAL_DETAILS(0x0F);
+                    CX_LAST, buffer->ptr,
+                    buffer->size, authorizationHash, 32)) {
+            sw = SW_TECHNICAL_PROBLEM_2;
             goto discardTransaction;
         }
     }
@@ -402,7 +411,7 @@ unsigned short apdu_hash_input_finalize_full_internal(
         if (!context_D.segwitParsedOnce) {
             if (context_D.usingOverwinter) {
                 if (cx_hash_no_throw(&context_D.transactionHashFull.blake2b.header, CX_LAST, context_D.segwit.cache.hashedOutputs, 0, context_D.segwit.cache.hashedOutputs, 32)) {
-                    sw = SW_TECHNICAL_DETAILS(0x0F);
+                    sw = SW_TECHNICAL_PROBLEM_2;
                     goto discardTransaction;
                 }
             }
@@ -411,11 +420,11 @@ unsigned short apdu_hash_input_finalize_full_internal(
                             CX_LAST,
                             context_D.segwit.cache.hashedOutputs, 0,
                             context_D.segwit.cache.hashedOutputs, 32)) {
-                    sw = SW_TECHNICAL_DETAILS(0x0F);
+                    sw = SW_TECHNICAL_PROBLEM_2;
                     goto discardTransaction;
                 }
                 if (cx_sha256_init_no_throw(&context_D.transactionHashFull.sha256)) {
-                    sw = SW_TECHNICAL_DETAILS(0x0F);
+                    sw = SW_TECHNICAL_PROBLEM_2;
                     goto discardTransaction;
                 }
                 if (cx_hash_no_throw(&context_D.transactionHashFull.sha256.header,
@@ -423,7 +432,7 @@ unsigned short apdu_hash_input_finalize_full_internal(
                             context_D.segwit.cache.hashedOutputs,
                             sizeof(context_D.segwit.cache.hashedOutputs),
                             context_D.segwit.cache.hashedOutputs, 32)) {
-                    sw = SW_TECHNICAL_DETAILS(0x0F);
+                    sw = SW_TECHNICAL_PROBLEM_2;
                     goto discardTransaction;
                 }
             }
@@ -431,7 +440,7 @@ unsigned short apdu_hash_input_finalize_full_internal(
             if (cx_hash_no_throw(
                         &context_D.transactionHashAuthorization.header,
                         CX_LAST, G_io_apdu_buffer, 0, authorizationHash, 32)) {
-                sw = SW_TECHNICAL_DETAILS(0x0F);
+                sw = SW_TECHNICAL_PROBLEM_2;
                 goto discardTransaction;
             }
             PRINTF("Auth Hash:\n%.*H\n", 32, authorizationHash);
@@ -442,7 +451,7 @@ unsigned short apdu_hash_input_finalize_full_internal(
                         (unsigned char *)&context_D.segwit.cache,
                         sizeof(context_D.segwit.cache),
                         authorizationHash, 32)) {
-                sw = SW_TECHNICAL_DETAILS(0x0F);
+                sw = SW_TECHNICAL_PROBLEM_2;
                 goto discardTransaction;
             }
             PRINTF("Auth Hash:\n%.*H\n", 32, authorizationHash);
@@ -479,7 +488,7 @@ unsigned short apdu_hash_input_finalize_full_internal(
         memmove(transactionSummary->authorizationHash,
                 authorizationHash,
                 sizeof(transactionSummary->authorizationHash));
-        goto return_OK;
+        return SW_OK;
     } else {
         if (os_secure_memcmp(
                     authorizationHash,
@@ -501,13 +510,12 @@ unsigned short apdu_hash_input_finalize_full_internal(
             context_D.transactionContext.transactionState =
                 TRANSACTION_SIGN_READY;
         }
-        sw = SW_OK;
+        hash_input_finalize_full_reset();
+        return SW_OK;
     }
-    apdu_hash_input_finalize_full_reset();
-    return sw;
 
 discardTransaction:
-    apdu_hash_input_finalize_full_reset();
+    hash_input_finalize_full_reset();
     ui_transaction_error();
     context_D.transactionContext.transactionState =
         TRANSACTION_NONE;
@@ -519,37 +527,43 @@ unsigned short apdu_hash_input_finalize_full_internal(
     return sw;
 }
 
-unsigned short apdu_hash_input_finalize_full() {
+unsigned short handler_hash_input_finalize_full(buffer_t* buffer, uint8_t p1, uint8_t p2) {
+    bool is_async = false;
     PRINTF("state=%d\n", context_D.outputParsingState);
-    unsigned short sw = apdu_hash_input_finalize_full_internal(
-        &context_D.transactionSummary);
-    if (context_D.io_flags & IO_ASYNCH_REPLY) {
+    unsigned short sw = hash_input_finalize_full_internal(
+        &context_D.transactionSummary, buffer, p1, p2, &is_async);
+
+    if (is_async) {
         // if the UI reject the processing of the request, then reply
         // immediately
-        bool status;
+        int status;
         if(context_D.outputParsingState == BIP44_CHANGE_PATH_VALIDATION) {
             context_D.outputParsingState = OUTPUT_PARSING_NUMBER_OUTPUTS;
-            return sw;
+            return 0;
         }
         else if (context_D.outputParsingState == OUTPUT_FINALIZE_TX) {
-            status = bagl_finalize_tx();
+            status = finalize_tx();
         }
         else {
-            status = bagl_confirm_single_output();
+            status = confirm_single_output();
         }
-        if (!status) {
+        if (status == 0) {
             ui_transaction_error();
-            context_D.io_flags &= ~IO_ASYNCH_REPLY;
             context_D.transactionContext.transactionState =
                 TRANSACTION_NONE;
             context_D.outLength = 0;
             sw = SW_INCORRECT_DATA;
+            return io_send_sw(sw);
+        }
+        else if (status == 2) {
+            return io_send_response_pointer(G_io_apdu_buffer, context_D.outLength, SW_OK);
         }
+        return 0;
     }
-    return sw;
+    return io_send_response_pointer(G_io_apdu_buffer, context_D.outLength, sw);
 }
 
-unsigned char bagl_user_action(unsigned char confirming) {
+unsigned char user_action(unsigned char confirming) {
     unsigned short sw = SW_OK;
 
     // confirm and finish the apdu exchange //spaghetti
@@ -570,12 +584,18 @@ unsigned char bagl_user_action(unsigned char confirming) {
                            context_D.discardSize);
             context_D.currentOutputOffset -=
                 context_D.discardSize;
-            context_D.io_flags &= ~IO_ASYNCH_REPLY;
-            while (handle_output_state() &&
-                   (!(context_D.io_flags & IO_ASYNCH_REPLY)))
-                ;
-            if (context_D.io_flags & IO_ASYNCH_REPLY) {
-                if (!bagl_confirm_single_output()) {
+            unsigned int processed = 1;
+            while (processed == 1) {
+                if (handle_output_state(&processed)) {
+                    context_D.transactionContext.transactionState =
+                        TRANSACTION_NONE;
+                    sw = SW_INCORRECT_DATA;
+                    break;
+                }
+            }
+
+            if (processed == 2) {
+                if (!confirm_single_output()) {
                     context_D.transactionContext.transactionState =
                         TRANSACTION_NONE;
                     sw = SW_INCORRECT_DATA;
@@ -594,7 +614,7 @@ unsigned char bagl_user_action(unsigned char confirming) {
              OUTPUT_PARSING_OUTPUT) &&
             (context_D.remainingOutputs == 0)) {
             context_D.outputParsingState = OUTPUT_FINALIZE_TX;
-            if (!bagl_finalize_tx()) {
+            if (!finalize_tx()) {
                 context_D.outputParsingState =
                     OUTPUT_PARSING_NONE;
                 context_D.transactionContext.transactionState =
@@ -622,8 +642,6 @@ unsigned char bagl_user_action(unsigned char confirming) {
                     TRANSACTION_SIGN_READY;
             }
         }
-        context_D.outLength -=
-            2; // status was already set by the last call
     } else {
         // Discard transaction
         context_D.transactionContext.transactionState =
@@ -631,17 +649,13 @@ unsigned char bagl_user_action(unsigned char confirming) {
         sw = SW_CONDITIONS_OF_USE_NOT_SATISFIED;
         context_D.outLength = 0;
     }
-    G_io_apdu_buffer[context_D.outLength++] = sw >> 8;
-    G_io_apdu_buffer[context_D.outLength++] = sw;
 
     if ((context_D.outputParsingState == OUTPUT_FINALIZE_TX) ||
         (sw != SW_OK)) {
 
         // we've finished the processing of the input
-        apdu_hash_input_finalize_full_reset();
+        hash_input_finalize_full_reset();
     }
+    return io_send_response_pointer(G_io_apdu_buffer, context_D.outLength, sw);
 
-    io_exchange(CHANNEL_APDU | IO_RETURN_AFTER_TX, context_D.outLength);
-
-    return 0;
 }
diff --git a/src/apdu_hash_input_start.c b/lib-app-bitcoin/handler/hash_input_start.c
similarity index 53%
rename from src/apdu_hash_input_start.c
rename to lib-app-bitcoin/handler/hash_input_start.c
index bc315ae5..f2906c67 100644
--- a/src/apdu_hash_input_start.c
+++ b/lib-app-bitcoin/handler/hash_input_start.c
@@ -15,9 +15,12 @@
 *  limitations under the License.
 ********************************************************************************/
 
-#include "internal.h"
+#include "io.h"
+
+#include "context.h"
+#include "transaction.h"
 #include "apdu_constants.h"
-#include "bagl_extensions.h"
+#include "extensions.h"
 #include "swap.h"
 
 #define P1_FIRST 0x00
@@ -29,58 +32,59 @@
 #define P2_NEW_SEGWIT_SAPLING 0x05
 #define P2_CONTINUE 0x80
 
-#define IS_INPUT()                                                          \
-    (G_io_apdu_buffer[ISO_OFFSET_LC] - 1 > 8                                \
-     && G_io_apdu_buffer[ISO_OFFSET_LC] - 1 <= TRUSTED_INPUT_TOTAL_SIZE + 2  \
-     && G_io_apdu_buffer[ISO_OFFSET_CDATA] <= 0x02)                         \
-
-#define IS_INPUT_TRUSTED()                                                  \
-    (G_io_apdu_buffer[ISO_OFFSET_CDATA] == 0x01                             \
-     && G_io_apdu_buffer[ISO_OFFSET_CDATA + 1] == TRUSTED_INPUT_TOTAL_SIZE   \
-     && G_io_apdu_buffer[ISO_OFFSET_CDATA + 2] == MAGIC_TRUSTED_INPUT       \
-     && G_io_apdu_buffer[ISO_OFFSET_CDATA + 3] == 0x00)
+#define IS_INPUT()                                        \
+    (buffer->size - 1 > 8                                 \
+     && buffer->size - 1 <= TRUSTED_INPUT_TOTAL_SIZE + 2  \
+     && buffer->ptr[0] <= 0x02)                           \
 
-unsigned short apdu_hash_input_start() {
-    unsigned char apduLength;
-    apduLength = G_io_apdu_buffer[ISO_OFFSET_LC];
+#define IS_INPUT_TRUSTED()                           \
+    (buffer->ptr[0] == 0x01                          \
+     && buffer->ptr[1] == TRUSTED_INPUT_TOTAL_SIZE   \
+     && buffer->ptr[2] == MAGIC_TRUSTED_INPUT        \
+     && buffer->ptr[3] == 0x00)
 
-    if (G_io_apdu_buffer[ISO_OFFSET_P1] == P1_FIRST) {
+WEAK unsigned short handler_hash_input_start(buffer_t* buffer, uint8_t p1, uint8_t p2) {
+    if (p1 == P1_FIRST) {
         // Initialize
         context_D.transactionContext.transactionState =
             TRANSACTION_NONE;
         context_D.transactionHashOption = TRANSACTION_HASH_BOTH;
-    } else if (G_io_apdu_buffer[ISO_OFFSET_P1] != P1_NEXT) {
-        return SW_INCORRECT_P1_P2;
+    } else if (p1 != P1_NEXT) {
+        return io_send_sw(SW_INCORRECT_P1_P2);
     }
 
-    if ((G_io_apdu_buffer[ISO_OFFSET_P2] == P2_NEW) ||
-        (G_io_apdu_buffer[ISO_OFFSET_P2] == P2_NEW_SEGWIT) ||
-        (G_io_apdu_buffer[ISO_OFFSET_P2] == P2_NEW_SEGWIT_CASHADDR) ||
-        (G_io_apdu_buffer[ISO_OFFSET_P2] == P2_NEW_SEGWIT_OVERWINTER) ||
-        (G_io_apdu_buffer[ISO_OFFSET_P2] == P2_NEW_SEGWIT_SAPLING)) {
-        if (G_io_apdu_buffer[ISO_OFFSET_P1] == P1_FIRST) {
+    if ((p2 == P2_NEW) ||
+        (p2 == P2_NEW_SEGWIT) ||
+        (p2 == P2_NEW_SEGWIT_CASHADDR) ||
+        (p2 == P2_NEW_SEGWIT_OVERWINTER) ||
+        (p2 == P2_NEW_SEGWIT_SAPLING)) {
+        if (p1 == P1_FIRST) {
             unsigned char usingSegwit =
-                (G_io_apdu_buffer[ISO_OFFSET_P2] == P2_NEW_SEGWIT) ||
-                (G_io_apdu_buffer[ISO_OFFSET_P2] == P2_NEW_SEGWIT_CASHADDR) ||
-                (G_io_apdu_buffer[ISO_OFFSET_P2] == P2_NEW_SEGWIT_OVERWINTER) ||
-                (G_io_apdu_buffer[ISO_OFFSET_P2] == P2_NEW_SEGWIT_SAPLING);
-            unsigned char usingCashAddr =
-                (G_io_apdu_buffer[ISO_OFFSET_P2] == P2_NEW_SEGWIT_CASHADDR);
+                (p2 == P2_NEW_SEGWIT) ||
+                (p2 == P2_NEW_SEGWIT_CASHADDR) ||
+                (p2 == P2_NEW_SEGWIT_OVERWINTER) ||
+                (p2 == P2_NEW_SEGWIT_SAPLING);
             // Master transaction reset
             context_D.transactionContext.firstSigned = 1;
             context_D.transactionContext.consumeP2SH = 0;
             context_D.transactionContext.relaxed = 0;
             context_D.usingSegwit = usingSegwit;
-            context_D.usingCashAddr =
-                (COIN_KIND == COIN_KIND_BITCOIN_CASH ? usingCashAddr
-                                                               : 0);
+
+            if (COIN_KIND == COIN_KIND_BITCOIN_CASH) {
+                unsigned char usingCashAddr = (p2 == P2_NEW_SEGWIT_CASHADDR);
+                context_D.usingCashAddr = usingCashAddr;
+            }
+            else {
+                context_D.usingCashAddr = 0;
+            }
+
             context_D.usingOverwinter = 0;
             if ((COIN_KIND == COIN_KIND_ZCASH) || (COIN_KIND == COIN_KIND_KOMODO) || (COIN_KIND == COIN_KIND_ZCLASSIC) || (COIN_KIND == COIN_KIND_RESISTANCE)) {
-                if (G_io_apdu_buffer[ISO_OFFSET_P2] == P2_NEW_SEGWIT_OVERWINTER) {
+                if (p2 == P2_NEW_SEGWIT_OVERWINTER) {
                     context_D.usingOverwinter = ZCASH_USING_OVERWINTER;
                 }
                 else
-                if (G_io_apdu_buffer[ISO_OFFSET_P2] == P2_NEW_SEGWIT_SAPLING) {
+                if (p2 == P2_NEW_SEGWIT_SAPLING) {
                     context_D.usingOverwinter = ZCASH_USING_OVERWINTER_SAPLING;
                 }
             }
@@ -94,15 +98,15 @@ unsigned short apdu_hash_input_start() {
             // segwit input when coontinuing from a previous session (P2=0x80)
             context_D.segwitWarningSeen = 0;
         }
-    } else if (G_io_apdu_buffer[ISO_OFFSET_P2] != P2_CONTINUE) {
-        return SW_INCORRECT_P1_P2;
+    } else if (p2 != P2_CONTINUE) {
+        return io_send_sw(SW_INCORRECT_P1_P2);
     }
 
     // In segwit mode, warn user one time only to update its client wallet...
     if (context_D.usingSegwit
         && !context_D.segwitWarningSeen
-        &&(G_io_apdu_buffer[ISO_OFFSET_P1] == P1_NEXT)
-        && (G_io_apdu_buffer[ISO_OFFSET_P2] != P2_CONTINUE)
+        && (p1 == P1_NEXT)
+        && (p2 != P2_CONTINUE)
         // ...if input is not passed as a TrustedInput
         && IS_INPUT()
         && !IS_INPUT_TRUSTED())
@@ -110,19 +114,23 @@ unsigned short apdu_hash_input_start() {
         if(G_called_from_swap){
             /* There is no point in displaying a warning when the app is signing
             in silent mode, as its UI is hidden behind the exchange app*/
-            return SW_SWAP_WITHOUT_TRUSTED_INPUTS;
+            return io_send_sw(SW_SWAP_WITHOUT_TRUSTED_INPUTS);
         }
         context_D.segwitWarningSeen = 1;
-        context_D.io_flags |= IO_ASYNCH_REPLY;
-        bagl_request_segwit_input_approval();
+        request_segwit_input_approval();
+        // Start parsing of the 1st chunk
+        context_D.transactionBufferPointer = (uint8_t*) buffer->ptr;
+        context_D.transactionDataRemaining = buffer->size;
+
+        transaction_parse(PARSE_MODE_SIGNATURE);
+        return 0;
     }
 
     // Start parsing of the 1st chunk
-    context_D.transactionBufferPointer =
-        G_io_apdu_buffer + ISO_OFFSET_CDATA;
-    context_D.transactionDataRemaining = apduLength;
+    context_D.transactionBufferPointer = (uint8_t*) buffer->ptr;
+    context_D.transactionDataRemaining = buffer->size;
 
     transaction_parse(PARSE_MODE_SIGNATURE);
 
-    return SW_OK;
+    return io_send_response_pointer(G_io_apdu_buffer, context_D.outLength, SW_OK);
 }
diff --git a/src/apdu_hash_sign.c b/lib-app-bitcoin/handler/hash_sign.c
similarity index 71%
rename from src/apdu_hash_sign.c
rename to lib-app-bitcoin/handler/hash_sign.c
index 9f670031..bd505aa7 100644
--- a/src/apdu_hash_sign.c
+++ b/lib-app-bitcoin/handler/hash_sign.c
@@ -15,15 +15,19 @@
 *  limitations under the License.
 ********************************************************************************/
 
-#include "internal.h"
+#include "macros.h"
+#include "io.h"
+#include "ledger_assert.h"
+#include "read.h"
+#include "write.h"
+#include "swap.h"
+
+#include "context.h"
+#include "helpers.h"
 #include "apdu_constants.h"
-#include "bagl_extensions.h"
+#include "extensions.h"
 #include "display_variables.h"
 #include "ui.h"
-#include "ledger_assert.h"
-#include "lib_standard_app/read.h"
-#include "lib_standard_app/write.h"
-#include "swap.h"
 
 #define SIGHASH_ALL 0x01
 
@@ -31,21 +35,20 @@
 #define COIN_FORKID 0
 #endif 
 
-unsigned short apdu_hash_sign() {
+WEAK unsigned short handler_hash_sign(buffer_t* buffer, uint8_t p1, uint8_t p2) {
     unsigned long int lockTime;
     uint32_t sighashType;
     unsigned char dataBuffer[8];
     unsigned char authorizationLength;
-    unsigned char *parameters = G_io_apdu_buffer + ISO_OFFSET_CDATA;
-    unsigned short sw = SW_TECHNICAL_DETAILS(0xF);
+    unsigned char *parameters = (uint8_t*)buffer->ptr;
 
-    if ((G_io_apdu_buffer[ISO_OFFSET_P1] != 0) ||
-        (G_io_apdu_buffer[ISO_OFFSET_P2] != 0)) {
-        return SW_INCORRECT_P1_P2;
+    if ((p1 != 0) || (p2 != 0)) {
+        return io_send_sw(SW_INCORRECT_P1_P2);
     }
 
-    if (G_io_apdu_buffer[ISO_OFFSET_LC] < (1 + 1 + 4 + 1)) {
-        return SW_INCORRECT_LENGTH;
+#define HASH_LENGTH 1 + 1 + 4 + 1
+    if (buffer->size < HASH_LENGTH) {
+        return io_send_sw(SW_INCORRECT_LENGTH);
     }
 
     // Zcash special - store parameters for later
@@ -55,7 +58,7 @@ unsigned short apdu_hash_sign() {
             (context_D.segwitParsedOnce) &&
             (context_D.transactionContext.transactionState == TRANSACTION_NONE)) {
         unsigned long int expiryHeight;
-        parameters += (4 * G_io_apdu_buffer[ISO_OFFSET_CDATA]) + 1;
+        parameters += (4 * buffer->ptr[0]) + 1;
         authorizationLength = *(parameters++);
         parameters += authorizationLength;
         lockTime = read_u32_be(parameters, 0);
@@ -66,31 +69,31 @@ unsigned short apdu_hash_sign() {
         write_u32_le(context_D.sigHashType, 0, sighashType);
         write_u32_le(context_D.nExpiryHeight, 0, expiryHeight);
         context_D.overwinterSignReady = 1;
-        return SW_OK;
+        return io_send_sw(SW_OK);
     }
 
     if (context_D.transactionContext.transactionState !=
             TRANSACTION_SIGN_READY) {
         PRINTF("Invalid transaction state %d\n", context_D.transactionContext.transactionState);
-        sw = SW_CONDITIONS_OF_USE_NOT_SATISFIED;
-        goto discardTransaction;
+        context_D.transactionContext.transactionState = TRANSACTION_NONE;
+        return io_send_sw(SW_CONDITIONS_OF_USE_NOT_SATISFIED);
     }
 
     if (context_D.usingOverwinter && !context_D.overwinterSignReady) {
         PRINTF("Overwinter not ready to sign\n");
-        sw = SW_CONDITIONS_OF_USE_NOT_SATISFIED;
-        goto discardTransaction;
+        context_D.transactionContext.transactionState = TRANSACTION_NONE;
+        return io_send_sw(SW_CONDITIONS_OF_USE_NOT_SATISFIED);
     }
 
     // Read parameters
-    if (G_io_apdu_buffer[ISO_OFFSET_CDATA] > MAX_BIP32_PATH) {
-        sw = SW_INCORRECT_DATA;
-        goto discardTransaction;
+    if (buffer->ptr[0] > MAX_BIP32_PATH) {
+        context_D.transactionContext.transactionState = TRANSACTION_NONE;
+        return io_send_sw(SW_INCORRECT_DATA);
     }
     memmove(context_D.transactionSummary.keyPath,
-            G_io_apdu_buffer + ISO_OFFSET_CDATA,
+            buffer->ptr,
             MAX_BIP32_PATH_LENGTH);
-    parameters += (4 * G_io_apdu_buffer[ISO_OFFSET_CDATA]) + 1;
+    parameters += (4 * buffer->ptr[0]) + 1;
     authorizationLength = *(parameters++);
     parameters += authorizationLength;
     lockTime = read_u32_be(parameters, 0);
@@ -98,18 +101,20 @@ unsigned short apdu_hash_sign() {
     sighashType = *(parameters++);
     context_D.transactionSummary.sighashType = sighashType;
 
-        // if bitcoin cash OR forkid is set, then use the fork id
-    if (COIN_KIND == COIN_KIND_BITCOIN_CASH || (COIN_FORKID)) {
+    // if bitcoin cash OR forkid is set, then use the fork id
+    if ((COIN_KIND == COIN_KIND_BITCOIN_CASH) ||
+            (COIN_FORKID)) {
 #define SIGHASH_FORKID 0x40
         if (sighashType != (SIGHASH_ALL | SIGHASH_FORKID)) {
-            sw = SW_INCORRECT_DATA;
-            goto discardTransaction;
+            context_D.transactionContext.transactionState = TRANSACTION_NONE;
+            return io_send_sw(SW_INCORRECT_DATA);
         }
         sighashType |= (COIN_FORKID << 8);
+
     } else {
         if (sighashType != SIGHASH_ALL) {
-            sw = SW_INCORRECT_DATA;
-            goto discardTransaction;
+            context_D.transactionContext.transactionState = TRANSACTION_NONE;
+            return io_send_sw(SW_INCORRECT_DATA);
         }
     }
 
@@ -120,20 +125,19 @@ unsigned short apdu_hash_sign() {
         PRINTF("--- ADD TO HASH FULL:\n%.*H\n", sizeof(dataBuffer), dataBuffer);
         if (cx_hash_no_throw(&context_D.transactionHashFull.sha256.header, 0,
                 dataBuffer, sizeof(dataBuffer), NULL, 0)) {
-            goto discardTransaction;
+            context_D.transactionContext.transactionState = TRANSACTION_NONE;
+            return io_send_sw(SW_INCORRECT_DATA);
         }
     }
 
     // Check if the path needs to be enforced
     if (!enforce_bip44_coin_type(context_D.transactionSummary.keyPath, false)) {
-        context_D.io_flags |= IO_ASYNCH_REPLY;
-        bagl_request_sign_path_approval(context_D.transactionSummary.keyPath);
+        request_sign_path_approval(context_D.transactionSummary.keyPath);
     }
     else {
         // Sign immediately
-        bagl_user_action_signtx(1, 1);
+        user_action_signtx(1, 0);
     }
-    sw = SW_OK;
     if (G_called_from_swap) {
         // if we signed all outputs we should exit,
         // but only after sending response, so lets raise the
@@ -142,17 +146,12 @@ unsigned short apdu_hash_sign() {
         if (vars.swap_data.alreadySignedInputs >= vars.swap_data.totalNumberOfInputs) {
             vars.swap_data.should_exit = 1;
         }
+        return io_send_response_pointer(G_io_apdu_buffer, context_D.outLength, SW_OK);
     }
-
-    return sw;
-
-    discardTransaction:
-        context_D.transactionContext.transactionState = TRANSACTION_NONE;
-        return sw;
+    return 0;
 }
 
-void bagl_user_action_signtx(unsigned char confirming, unsigned char direct) {
-    unsigned short sw = SW_OK;
+int user_action_signtx(unsigned char confirming, unsigned char direct) {
     // confirm and finish the apdu exchange //spaghetti
     if (confirming) {
         unsigned char hash[32];
@@ -174,23 +173,20 @@ void bagl_user_action_signtx(unsigned char confirming, unsigned char direct) {
             context_D.transactionSummary.keyPath,
             sizeof(context_D.transactionSummary.keyPath),
             hash, sizeof(hash),
-            G_io_apdu_buffer, &out_len,
-            1);
+            G_io_apdu_buffer, &out_len);
 
         context_D.outLength = G_io_apdu_buffer[1] + 2;
         G_io_apdu_buffer[context_D.outLength++] = context_D.transactionSummary.sighashType;
         ui_transaction_finish();
 
     } else {
-        sw = SW_CONDITIONS_OF_USE_NOT_SATISFIED;
         context_D.outLength = 0;
+        return io_send_sw(SW_CONDITIONS_OF_USE_NOT_SATISFIED);
     }
 
     if (!direct) {
-        G_io_apdu_buffer[context_D.outLength++] = sw >> 8;
-        G_io_apdu_buffer[context_D.outLength++] = sw;
-
-        io_exchange(CHANNEL_APDU | IO_RETURN_AFTER_TX, context_D.outLength);
+        return io_send_response_pointer(G_io_apdu_buffer, context_D.outLength, SW_OK);
     }
+    return 0;
 }
 
diff --git a/src/apdu_sign_message.c b/lib-app-bitcoin/handler/sign_message.c
similarity index 71%
rename from src/apdu_sign_message.c
rename to lib-app-bitcoin/handler/sign_message.c
index 9a5bbc54..782e27b4 100644
--- a/src/apdu_sign_message.c
+++ b/lib-app-bitcoin/handler/sign_message.c
@@ -15,11 +15,13 @@
 *  limitations under the License.
 ********************************************************************************/
 
-#include "internal.h"
+#include "context.h"
+#include "helpers.h"
 #include "apdu_constants.h"
-#include "bagl_extensions.h"
+#include "extensions.h"
 #include "lib_standard_app/read.h"
 #include "swap.h"
+#include "io.h"
 
 #define P1_PREPARE 0x00
 #define P1_SIGN 0x80
@@ -31,11 +33,11 @@
 #define BITID_POWERCYCLE 1
 #define BITID_MULTIPLE 2
 
-//#define SLIP_13 0x8000000D
+unsigned char const SIGNMAGIC[] = {' ', 'S', 'i', 'g', 'n', 'e', 'd', ' ', 'M',
+                                   'e', 's', 's', 'a', 'g', 'e', ':', '\n'};
 
-unsigned short compute_hash(void);
-
-unsigned char checkBitId(unsigned char *bip32Path) {
+// TODO : support longer messages
+unsigned char message_check_bit_id(unsigned char *bip32Path) {
     unsigned char i;
     unsigned char bip32PathLength = bip32Path[0];
     bip32Path++;
@@ -53,21 +55,48 @@ unsigned char checkBitId(unsigned char *bip32Path) {
     return BITID_NONE;
 }
 
-// TODO : support longer messages
+unsigned short message_compute_hash(void) {
+    unsigned char hash[32];
+    unsigned short sw = SW_OK;
+
+    context_D.outLength = 0;
+    if (cx_hash_no_throw(&context_D.transactionHashFull.sha256.header, CX_LAST, hash,
+                0, hash, 32)) {
+        goto discard;
+    }
+            
+    if (cx_hash_sha256(hash, sizeof(hash), hash, 32) == 0) {
+        goto discard;
+    }
+
+    size_t out_len = 100;
+    sign_finalhash(
+            context_D.transactionSummary.keyPath,
+            sizeof(context_D.transactionSummary.keyPath),
+            hash, sizeof(hash), // IN
+            G_io_apdu_buffer, &out_len);                        // OUT
+    context_D.outLength = G_io_apdu_buffer[1] + 2;
+            memset(&context_D.transactionSummary, 0,
+                      sizeof(transaction_summary_t));
+    return sw;
 
-unsigned short apdu_sign_message_internal() {
+    discard: 
+            sw = SW_TECHNICAL_PROBLEM_2;
+            return sw;
+}
+
+
+static unsigned short sign_message_internal(buffer_t* buffer, uint8_t p1, uint8_t p2) {
     unsigned short sw = SW_OK;
-    unsigned char p1 = G_io_apdu_buffer[ISO_OFFSET_P1];
-    unsigned char p2 = G_io_apdu_buffer[ISO_OFFSET_P2];
-    unsigned char apduLength = G_io_apdu_buffer[ISO_OFFSET_LC];
-    unsigned short offset = ISO_OFFSET_CDATA;
+    unsigned char apduLength = buffer->size;
+    unsigned short offset = 0;
 
     if ((p1 != P1_PREPARE) && (p1 != P1_SIGN)) {
-        return SW_INCORRECT_P1_P2;
+        return io_send_sw(SW_INCORRECT_P1_P2);
     }
     if (p1 == P1_PREPARE) {
         if ((p2 != P2_FIRST) && (p2 != P2_OTHER) && (p2 != P2_LEGACY)) {
-            return SW_INCORRECT_P1_P2;
+            return io_send_sw(SW_INCORRECT_P1_P2);
         }
     }
 
@@ -78,7 +107,7 @@ unsigned short apdu_sign_message_internal() {
             unsigned char messageLengthSize;
             memset(&context_D.transactionSummary, 0,
                     sizeof(transaction_summary_t));
-            if (G_io_apdu_buffer[offset] > MAX_BIP32_PATH) {
+            if (buffer->ptr[0] > MAX_BIP32_PATH) {
                 PRINTF("Invalid path\n");
                 sw = SW_INCORRECT_DATA;
                 goto discard;
@@ -87,16 +116,16 @@ unsigned short apdu_sign_message_internal() {
             context_D.transactionSummary.payToScriptHashVersion = COIN_P2SH_VERSION;
             memmove(
                     context_D.transactionSummary.keyPath,
-                    G_io_apdu_buffer + offset, MAX_BIP32_PATH_LENGTH);
-            offset += (4 * G_io_apdu_buffer[offset]) + 1;
+                    buffer->ptr, MAX_BIP32_PATH_LENGTH);
+            offset += (4 * buffer->ptr[0]) + 1;
             if (p2 == P2_LEGACY) {
                 context_D.transactionSummary.messageLength =
-                    G_io_apdu_buffer[offset];
+                    buffer->ptr[offset];
                 offset++;
             } else {
                 context_D.transactionSummary.messageLength =
-                    (G_io_apdu_buffer[offset] << 8) |
-                    (G_io_apdu_buffer[offset + 1]);
+                    (buffer->ptr[offset] << 8) |
+                    (buffer->ptr[offset + 1]);
                 offset += 2;
             }
             if (context_D.transactionSummary.messageLength ==
@@ -106,20 +135,16 @@ unsigned short apdu_sign_message_internal() {
                 goto discard;
             }
             context_D.hashedMessageLength = 0;
-            if (cx_sha256_init_no_throw(&context_D.transactionHashFull.sha256)) {
-                sw = SW_TECHNICAL_DETAILS(0x0F);
-                goto discard;
-            }
-            if (cx_sha256_init_no_throw(
-                        &context_D.transactionHashAuthorization)) {
-                sw = SW_TECHNICAL_DETAILS(0x0F);
-                goto discard;
-            }
+
             // Horizen signed message magic header is "Zcash"
             // See https://github.com/HorizenOfficial/zen/blob/v5.0.0/src/main.cpp#L122
             const char* magicHeader = (COIN_KIND != COIN_KIND_HORIZEN) ? COIN_COINID : "Zcash";
+
+            cx_sha256_init_no_throw(&context_D.transactionHashFull.sha256);
+            cx_sha256_init_no_throw(&context_D.transactionHashAuthorization);
+
             chunkLength =
-                strlen(magicHeader) + SIGNMAGIC_LENGTH;
+                strlen(magicHeader) + sizeof(SIGNMAGIC);
             if (cx_hash_no_throw(&context_D.transactionHashFull.sha256.header, 0,
                         &chunkLength, 1, NULL, 0)) {
                 goto discard;
@@ -127,12 +152,12 @@ unsigned short apdu_sign_message_internal() {
             if (cx_hash_no_throw(&context_D.transactionHashFull.sha256.header, 0,
                         (uint8_t *)magicHeader,
                         strlen(magicHeader), NULL, 0)) {
-                sw = SW_TECHNICAL_DETAILS(0x0F);
+                sw = SW_TECHNICAL_PROBLEM_2;
                 goto discard;
             }
             if (cx_hash_no_throw(&context_D.transactionHashFull.sha256.header, 0,
-                        (unsigned char *)SIGNMAGIC, SIGNMAGIC_LENGTH, NULL, 0)) {
-                sw = SW_TECHNICAL_DETAILS(0x0F);
+                        (unsigned char *)SIGNMAGIC, sizeof(SIGNMAGIC), NULL, 0)) {
+                sw = SW_TECHNICAL_PROBLEM_2;
                 goto discard;
             }
             if (context_D.transactionSummary.messageLength <
@@ -153,10 +178,10 @@ unsigned short apdu_sign_message_internal() {
             }
             if (cx_hash_no_throw(&context_D.transactionHashFull.sha256.header, 0,
                         messageLength, messageLengthSize, NULL, 0)) {
-                sw = SW_TECHNICAL_DETAILS(0x0F);
+                sw = SW_TECHNICAL_PROBLEM_2;
                 goto discard;
             }
-            chunkLength = apduLength - (offset - ISO_OFFSET_CDATA);
+            chunkLength = apduLength - offset;
             if ((context_D.hashedMessageLength + chunkLength) >
                     context_D.transactionSummary.messageLength) {
                 PRINTF("Invalid data length\n");
@@ -164,14 +189,14 @@ unsigned short apdu_sign_message_internal() {
                 goto discard;
             }
             if (cx_hash_no_throw(&context_D.transactionHashFull.sha256.header, 0,
-                        G_io_apdu_buffer + offset, chunkLength, NULL, 0)) {
-                sw = SW_TECHNICAL_DETAILS(0x0F);
+                        buffer->ptr + offset, chunkLength, NULL, 0)) {
+                sw = SW_TECHNICAL_PROBLEM_2;
                 goto discard;
             }
             if (cx_hash_no_throw(
                         &context_D.transactionHashAuthorization.header,
-                        0, G_io_apdu_buffer + offset, chunkLength, NULL, 0)) {
-                sw = SW_TECHNICAL_DETAILS(0x0F);
+                        0, buffer->ptr + offset, chunkLength, NULL, 0)) {
+                sw = SW_TECHNICAL_PROBLEM_2;
                 goto discard;
             }
             context_D.hashedMessageLength += chunkLength;
@@ -191,14 +216,14 @@ unsigned short apdu_sign_message_internal() {
                 goto discard;
             }
             if (cx_hash_no_throw(&context_D.transactionHashFull.sha256.header, 0,
-                        G_io_apdu_buffer + offset, apduLength, NULL, 0)) {
-                sw = SW_TECHNICAL_DETAILS(0x0F);
+                        buffer->ptr + offset, apduLength, NULL, 0)) {
+                sw = SW_TECHNICAL_PROBLEM_2;
                 goto discard;
             }
             if (cx_hash_no_throw(
                         &context_D.transactionHashAuthorization.header,
-                        0, G_io_apdu_buffer + offset, apduLength, NULL, 0)) {
-                sw = SW_TECHNICAL_DETAILS(0x0F);
+                        0, buffer->ptr + offset, apduLength, NULL, 0)) {
+                sw = SW_TECHNICAL_PROBLEM_2;
                 goto discard;
             }
             context_D.hashedMessageLength += apduLength;
@@ -219,72 +244,36 @@ unsigned short apdu_sign_message_internal() {
             sw = SW_INCORRECT_DATA;
             goto discard;
         }
-        if (checkBitId(context_D.transactionSummary.keyPath) != BITID_NONE) {
-            sw = compute_hash();
+        if (message_check_bit_id(context_D.transactionSummary.keyPath) != BITID_NONE) {
+            sw = message_compute_hash();
         } else {
-            context_D.io_flags |= IO_ASYNCH_REPLY;
-            return SW_OK;
+            confirm_message_signature();
+            return 0;
         }
     }
-    return sw;
+    return io_send_response_pointer(G_io_apdu_buffer, context_D.outLength, sw);
 
     discard : 
         memset(&context_D.transactionSummary, 0,
                   sizeof(transaction_summary_t));
-        return sw;
+        return io_send_sw(sw);
 }
 
-unsigned short apdu_sign_message() {
+WEAK unsigned short handler_sign_message(buffer_t* buffer, uint8_t p1, uint8_t p2) {
     if (G_called_from_swap) {
-        return SW_SECURITY_STATUS_NOT_SATISFIED;
-    }
-    unsigned short sw = apdu_sign_message_internal();
-    if (context_D.io_flags & IO_ASYNCH_REPLY) {
-        bagl_confirm_message_signature();
+        return io_send_sw(SW_SECURITY_STATUS_NOT_SATISFIED);
     }
-    return sw;
-}
 
-unsigned short compute_hash() {
-    unsigned char hash[32];
-    unsigned short sw = SW_OK;
-
-    context_D.outLength = 0;
-    if (cx_hash_no_throw(&context_D.transactionHashFull.sha256.header, CX_LAST, hash,
-                0, hash, 32)) {
-        goto discard;
-    }
-            
-    if (cx_hash_sha256(hash, sizeof(hash), hash, 32) == 0) {
-        goto discard;
-    }
-
-    size_t out_len = 100;
-    sign_finalhash(
-            context_D.transactionSummary.keyPath,
-            sizeof(context_D.transactionSummary.keyPath),
-            hash, sizeof(hash), // IN
-            G_io_apdu_buffer, &out_len,                        // OUT
-            1);
-    context_D.outLength = G_io_apdu_buffer[1] + 2;
-            memset(&context_D.transactionSummary, 0,
-                      sizeof(transaction_summary_t));
-    return sw;
-
-    discard: 
-            sw = SW_TECHNICAL_DETAILS(0x0F);
-            return sw;
+    return sign_message_internal(buffer, p1, p2);
 }
 
-void bagl_user_action_message_signing(unsigned char confirming) {
+int user_action_message_signing(unsigned char confirming) {
     unsigned short sw;
     if (confirming) {
-        sw = compute_hash();
+        sw = message_compute_hash();
+        return io_send_response_pointer(G_io_apdu_buffer, context_D.outLength, sw);
     } else {
-        sw = SW_CONDITIONS_OF_USE_NOT_SATISFIED;
+        context_D.outLength = 0;
+        return io_send_sw(SW_CONDITIONS_OF_USE_NOT_SATISFIED);
     }
-    G_io_apdu_buffer[context_D.outLength++] = sw >> 8;
-    G_io_apdu_buffer[context_D.outLength++] = sw;
-
-    io_exchange(CHANNEL_APDU | IO_RETURN_AFTER_TX, context_D.outLength);
 }
diff --git a/lib-app-bitcoin/helpers.c b/lib-app-bitcoin/helpers.c
new file mode 100644
index 00000000..b640fb6c
--- /dev/null
+++ b/lib-app-bitcoin/helpers.c
@@ -0,0 +1,233 @@
+/*******************************************************************************
+*   Ledger App - Bitcoin Wallet
+*   (c) 2016-2019 Ledger
+*
+*  Licensed under the Apache License, Version 2.0 (the "License");
+*  you may not use this file except in compliance with the License.
+*  You may obtain a copy of the License at
+*
+*      http://www.apache.org/licenses/LICENSE-2.0
+*
+*  Unless required by applicable law or agreed to in writing, software
+*  distributed under the License is distributed on an "AS IS" BASIS,
+*  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+*  See the License for the specific language governing permissions and
+*  limitations under the License.
+********************************************************************************/
+
+#include "lib_standard_app/crypto_helpers.h"
+#include "lib_standard_app/bip32.h"
+#include "ledger_assert.h"
+#include "io.h"
+#include "base58.h"
+#include "read.h"
+
+#include "context.h"
+#include "helpers.h"
+
+void public_key_hash160(unsigned char *in, unsigned short inlen,
+                               unsigned char *out) {
+    cx_ripemd160_t riprip;
+    unsigned char buffer[32];
+    cx_hash_sha256(in, inlen, buffer, 32);
+    cx_ripemd160_init(&riprip);
+    LEDGER_ASSERT(cx_hash_no_throw(&riprip.header, CX_LAST, buffer, 32, out, 20) == CX_OK, "hash160");
+}
+
+void compute_checksum(unsigned char* in, unsigned short inlen, unsigned char * output) {
+    unsigned char checksumBuffer[32];
+    cx_hash_sha256(in, inlen, checksumBuffer, 32);
+    cx_hash_sha256(checksumBuffer, 32, checksumBuffer, 32);
+
+    PRINTF("Checksum\n%.*H\n",4,checksumBuffer);
+    memmove(output, checksumBuffer, 4);
+}
+
+unsigned short public_key_to_encoded_base58(
+    unsigned char *in, unsigned short inlen, unsigned char *out,
+    unsigned short outlen, unsigned short version,
+    unsigned char alreadyHashed) {
+    unsigned char tmpBuffer[34];
+
+    unsigned char versionSize = (version > 255 ? 2 : 1);
+    short outputLen;
+
+    if (!alreadyHashed) {
+        PRINTF("To hash\n%.*H\n",inlen,in);
+        public_key_hash160(in, inlen, tmpBuffer + versionSize);
+        PRINTF("Hash160\n%.*H\n",20,(tmpBuffer + versionSize));
+        if (version > 255) {
+            tmpBuffer[0] = (version >> 8);
+            tmpBuffer[1] = version;
+        } else {
+            tmpBuffer[0] = version;
+        }
+    } else {
+        memmove(tmpBuffer, in, 20 + versionSize);
+    }
+
+    compute_checksum(tmpBuffer, 20 + versionSize, tmpBuffer + 20 + versionSize);
+
+    outputLen = base58_encode(tmpBuffer, 24 + versionSize, (char *)out, outlen);
+    LEDGER_ASSERT(outputLen >= 0, "Error encoding public key");
+
+    return outputLen;
+}
+
+void swap_bytes(unsigned char *target, unsigned char *source,
+                       unsigned char size) {
+    unsigned char i;
+    for (i = 0; i < size; i++) {
+        target[i] = source[size - 1 - i];
+    }
+}
+
+/*
+Checks if the values of a derivation path are within "normal" (arbitrary) ranges:
+Account < 100, change == 1 or 0, address index < 50000
+Returns 1 if the path is unusual, or not compliant with BIP44*/
+unsigned char bip44_derivation_guard(const unsigned char *bip32Path, bool is_change_path) {
+    unsigned char path_len;
+    bip32_path_t bip32PathInt;
+
+    path_len = bip32Path[0];
+    if (!parse_serialized_path(&bip32PathInt, bip32Path, MAX_BIP32_PATH_LENGTH)) {
+        return 1;
+    }
+
+    // If the path length is not compliant with BIP44 or if the purpose don't match regular usage, return a warning
+    if(path_len != BIP44_PATH_LEN ||
+       ((bip32PathInt.path[BIP44_PURPOSE_OFFSET]^0x80000000) != 44 &&
+       (bip32PathInt.path[BIP44_PURPOSE_OFFSET]^0x80000000) != 49 &&
+       (bip32PathInt.path[BIP44_PURPOSE_OFFSET]^0x80000000) != 84)) {
+        return 1;
+    }
+
+    // If the coin type doesn't match, return a warning
+    if ((BIP44_COIN_TYPE != 0) &&
+        (((bip32PathInt.path[BIP44_COIN_TYPE_OFFSET]^0x80000000) != BIP44_COIN_TYPE) &&
+          ((bip32PathInt.path[BIP44_COIN_TYPE_OFFSET]^0x80000000) != BIP44_COIN_TYPE_2))) {
+        return 1;
+    }
+
+    // If the account or address index is very high or if the change isn't 1, return a warning
+    if((bip32PathInt.path[BIP44_ACCOUNT_OFFSET]^0x80000000) > MAX_BIP44_ACCOUNT_RECOMMENDED ||
+       bip32PathInt.path[BIP44_CHANGE_OFFSET] != is_change_path?1:0 ||
+       bip32PathInt.path[BIP44_ADDRESS_INDEX_OFFSET] > MAX_BIP44_ADDRESS_INDEX_RECOMMENDED) {
+        return 1;
+    }
+
+    return 0;
+}
+
+/*
+Only enforce the structure or coin type for consumed UTXOs or a public address
+Returns 0 if the path is non compliant, or 1 if compliant
+*/
+unsigned char enforce_bip44_coin_type(const unsigned char *bip32Path, bool for_pubkey) {
+    bip32_path_t bip32PathInt;
+    // No enforcement required
+    if (BIP44_COIN_TYPE == 0) {
+        return 1;
+    }
+    // Path is too short - always require a user validation if signing
+    if (bip32Path[0] < 2) {
+        return for_pubkey;
+    }
+
+    if (!parse_serialized_path(&bip32PathInt, bip32Path, MAX_BIP32_PATH_LENGTH)) {
+        return 1;
+    }
+
+    // Path is not compliant with BIP 44 or derivatives - valid if not signing
+    if (!(((bip32PathInt.path[BIP44_PURPOSE_OFFSET]^0x80000000) == 44 ||
+       (bip32PathInt.path[BIP44_PURPOSE_OFFSET]^0x80000000) == 49 ||
+       (bip32PathInt.path[BIP44_PURPOSE_OFFSET]^0x80000000) == 84))) {
+        return for_pubkey;
+    }
+
+    if  (((bip32PathInt.path[BIP44_COIN_TYPE_OFFSET]^0x80000000) == BIP44_COIN_TYPE) ||
+        ((bip32PathInt.path[BIP44_COIN_TYPE_OFFSET]^0x80000000) == BIP44_COIN_TYPE_2)) {
+        // Valid BIP 44 path
+        return 1;
+    }
+    // Everything else needs a user validation
+    return 0;
+}
+
+int sign_finalhash(unsigned char* path, size_t path_len, unsigned char *in, unsigned short inlen,
+                                 unsigned char *out, size_t* outlen) {
+
+    unsigned int info = 0;
+
+    io_seproxyhal_io_heartbeat();
+    
+    bip32_path_t bip32Path;
+    bip32Path.length = path[0];
+
+    if (!parse_serialized_path(&bip32Path, path, path_len)) {
+        return -1;
+    }
+
+    if (bip32_derive_ecdsa_sign_hash_256(
+            CX_CURVE_SECP256K1,
+            bip32Path.path, 
+            bip32Path.length,
+            CX_LAST | CX_RND_RFC6979,
+            CX_SHA256,
+            in, 
+            inlen, 
+            out, 
+            outlen,
+            &info) != CX_OK) {
+        return -1;
+    }
+
+    // Store information about the parity of the 'y' coordinate
+    if (info & CX_ECCINFO_PARITY_ODD) {
+        out[0] |= 0x01;
+    }
+
+    io_seproxyhal_io_heartbeat();
+    return 0;
+}
+
+int get_public_key(const unsigned char* keyPath, size_t keyPath_len, uint8_t raw_pubkey[static 65], unsigned char* chainCode) {
+
+    bip32_path_t bip32Path;
+
+    if (!parse_serialized_path(&bip32Path, keyPath, keyPath_len)) {
+        return -1;
+    }
+
+    if (bip32_derive_get_pubkey_256(
+        CX_CURVE_SECP256K1,
+        bip32Path.path, 
+        bip32Path.length,
+        raw_pubkey,
+        chainCode,
+        CX_SHA512) != CX_OK) 
+    {
+        return -1;
+    }
+
+    return 0;
+}
+
+void compress_public_key_value(unsigned char *value) {
+    bool odd = (value[64] & 1);
+    value[0] = odd ? 0x03 : 0x02;
+}
+
+bool parse_serialized_path(bip32_path_t* path, const unsigned char* serialized_path, unsigned char serialized_path_length) {
+    if (serialized_path_length < 1 ||
+        serialized_path[0] > MAX_BIP32_PATH ||
+        serialized_path[0] * 4 + 1 > serialized_path_length)
+        return false;
+    path->length = serialized_path[0];
+    serialized_path++;
+    for (int i = 0; i < path->length; i += 1, serialized_path += 4) {
+        path->path[i] = read_u32_be(serialized_path, 0);
+    }
+    return true;
+}
diff --git a/include/helpers.h b/lib-app-bitcoin/helpers.h
similarity index 57%
rename from include/helpers.h
rename to lib-app-bitcoin/helpers.h
index febe122a..713dfa1b 100644
--- a/include/helpers.h
+++ b/lib-app-bitcoin/helpers.h
@@ -15,13 +15,12 @@
 *  limitations under the License.
 ********************************************************************************/
 
-#ifndef HELPERS_H
-
-#define HELPERS_H
+#pragma once
 
 #include "os.h"
 #include "cx.h"
 #include "stdbool.h"
+#include "filesystem_tx.h"
 
 #define OUTPUT_SCRIPT_REGULAR_PRE_LENGTH 4
 #define OUTPUT_SCRIPT_REGULAR_POST_LENGTH 2
@@ -30,15 +29,10 @@
 
 #define OUTPUT_SCRIPT_NATIVE_WITNESS_PROGRAM_OFFSET 3
 
-unsigned char output_script_is_regular(unsigned char *buffer);
-unsigned char output_script_is_p2sh(unsigned char *buffer);
-unsigned char output_script_is_op_return(unsigned char *buffer);
-unsigned char output_script_is_native_witness(unsigned char *buffer);
-
-unsigned char output_script_is_op_create(unsigned char *buffer,
-                                                size_t size);
-unsigned char output_script_is_op_call(unsigned char *buffer,
-                                                size_t size);
+typedef struct bip32_path {
+    unsigned char length;
+    unsigned int path[MAX_BIP32_PATH];
+} bip32_path_t;
 
 void public_key_hash160(unsigned char *in, unsigned short inlen,
                                unsigned char *out);
@@ -46,20 +40,18 @@ unsigned short public_key_to_encoded_base58(
     unsigned char *in, unsigned short inlen, unsigned char *out,
     unsigned short outlen, unsigned short version, unsigned char alreadyHashed);
 
-unsigned char bip44_derivation_guard(unsigned char *bip32Path, bool is_change_path);
-unsigned char enforce_bip44_coin_type(unsigned char *bip32Path, bool for_pubkey);
-unsigned char bip32_print_path(unsigned char *bip32Path, char* out, unsigned char max_out_len);
+unsigned char bip44_derivation_guard(const unsigned char *bip32Path, bool is_change_path);
+unsigned char enforce_bip44_coin_type(const unsigned char *bip32Path, bool for_pubkey);
 
 void swap_bytes(unsigned char *target, unsigned char *source,
                        unsigned char size);
 
 int sign_finalhash(unsigned char *path, size_t path_len,
                            unsigned char *in, unsigned short inlen,
-                           unsigned char *out, size_t* outlen,
-                           unsigned char rfc6979);
+                           unsigned char *out, size_t* outlen);
+
+int get_public_key(const unsigned char* keyPath, size_t keyPath_len, uint8_t raw_pubkey[static 65], unsigned char* chainCode);
 
-void transaction_add_output(unsigned char *hash160Address,
-                                   unsigned char *amount, unsigned char p2sh);
-int get_public_key(unsigned char* keyPath, size_t keyPath_len, uint8_t raw_pubkey[static 65], unsigned char* chainCode);
+void compress_public_key_value(unsigned char *value);
 
-#endif
+bool parse_serialized_path(bip32_path_t* path, const unsigned char* serialized_path, unsigned char serialized_path_length);
diff --git a/src/swap/handle_check_address.c b/lib-app-bitcoin/swap/handle_check_address.c
similarity index 93%
rename from src/swap/handle_check_address.c
rename to lib-app-bitcoin/swap/handle_check_address.c
index 1fd13dec..95e6d166 100644
--- a/src/swap/handle_check_address.c
+++ b/lib-app-bitcoin/swap/handle_check_address.c
@@ -1,14 +1,19 @@
 #include "handle_check_address.h"
-#include "os.h"
 #include "helpers.h"
-#include "bip32_path.h"
-#include "ecc.h"
-#include "apdu_get_wallet_public_key.h"
+#include "context.h"
 #include "cashaddr.h"
 #include "segwit_addr.h"
-#include <string.h>
 
-bool derive_compressed_public_key(
+#define P1_NO_DISPLAY 0x00
+#define P1_DISPLAY 0x01
+#define P1_REQUEST_TOKEN 0x02
+
+#define P2_LEGACY 0x00
+#define P2_SEGWIT 0x01
+#define P2_NATIVE_SEGWIT 0x02
+#define P2_CASHADDR 0x03
+
+static bool derive_compressed_public_key(
     unsigned char* serialized_path, unsigned char serialized_path_length,
     unsigned char* public_key, unsigned char public_key_length) {
     UNUSED(public_key_length);
@@ -23,7 +28,7 @@ bool derive_compressed_public_key(
     return true;
 }
 
-bool get_address_from_compressed_public_key(
+static bool get_address_from_compressed_public_key(
     unsigned char format,
     unsigned char* compressed_pub_key,
     unsigned short payToAddressVersion,
diff --git a/src/swap/handle_check_address.h b/lib-app-bitcoin/swap/handle_check_address.h
similarity index 91%
rename from src/swap/handle_check_address.h
rename to lib-app-bitcoin/swap/handle_check_address.h
index 01d8e138..2e5eaa54 100644
--- a/src/swap/handle_check_address.h
+++ b/lib-app-bitcoin/swap/handle_check_address.h
@@ -2,7 +2,6 @@
 #define _HANDLE_CHECK_ADDRESS_H_
 
 #include "swap_lib_calls.h"
-#include "context.h"
 
 void swap_handle_check_address(check_address_parameters_t* check_address_params);
 
diff --git a/lib-app-bitcoin/swap/handle_get_printable_amount.c b/lib-app-bitcoin/swap/handle_get_printable_amount.c
new file mode 100644
index 00000000..d801bfab
--- /dev/null
+++ b/lib-app-bitcoin/swap/handle_get_printable_amount.c
@@ -0,0 +1,20 @@
+#include "read.h"
+
+#include "handle_get_printable_amount.h"
+#include "display_utils.h"
+
+void swap_handle_get_printable_amount(get_printable_amount_parameters_t* params) {
+    params->printable_amount[0] = 0;
+    if (params->amount_length > 8) {
+        PRINTF("Amount is too big");
+        return;
+    }
+    unsigned char amount[8];
+    memset(amount, 0, 8);
+    memcpy(amount + (8 - params->amount_length), params->amount, params->amount_length);
+
+    format_sats_amount(COIN_COINID_SHORT,
+            (uint64_t)(read_u64_be(amount, 0)), // Cast prevents weird compilo bug
+            params->printable_amount);
+    return;
+}
\ No newline at end of file
diff --git a/src/swap/handle_get_printable_amount.h b/lib-app-bitcoin/swap/handle_get_printable_amount.h
similarity index 100%
rename from src/swap/handle_get_printable_amount.h
rename to lib-app-bitcoin/swap/handle_get_printable_amount.h
diff --git a/src/swap/handle_swap_sign_transaction.c b/lib-app-bitcoin/swap/handle_swap_sign_transaction.c
similarity index 98%
rename from src/swap/handle_swap_sign_transaction.c
rename to lib-app-bitcoin/swap/handle_swap_sign_transaction.c
index c29af60c..61e4d0a1 100644
--- a/src/swap/handle_swap_sign_transaction.c
+++ b/lib-app-bitcoin/swap/handle_swap_sign_transaction.c
@@ -1,6 +1,5 @@
 #include "handle_swap_sign_transaction.h"
 #include "os_io_seproxyhal.h"
-#include "public_ram_variables.h"
 #include "display_variables.h"
 #include "context.h"
 #include "usbd_core.h"
diff --git a/src/swap/handle_swap_sign_transaction.h b/lib-app-bitcoin/swap/handle_swap_sign_transaction.h
similarity index 94%
rename from src/swap/handle_swap_sign_transaction.h
rename to lib-app-bitcoin/swap/handle_swap_sign_transaction.h
index 7203d065..be98246e 100644
--- a/src/swap/handle_swap_sign_transaction.h
+++ b/lib-app-bitcoin/swap/handle_swap_sign_transaction.h
@@ -2,7 +2,6 @@
 #define _HANDLE_SWAP_SIGN_TRANSACTION_H_
 
 #include "swap_lib_calls.h"
-#include "context.h"
 
 bool swap_copy_transaction_parameters(create_transaction_parameters_t* sign_transaction_params);
 
diff --git a/src/transaction.c b/lib-app-bitcoin/transaction.c
similarity index 89%
rename from src/transaction.c
rename to lib-app-bitcoin/transaction.c
index 2806d623..cf47caa4 100644
--- a/src/transaction.c
+++ b/lib-app-bitcoin/transaction.c
@@ -15,14 +15,19 @@
 *  limitations under the License.
 ********************************************************************************/
 
-#include "internal.h"
-#include "apdu_constants.h"
-#include "display_variables.h"
 #include "ledger_assert.h"
 #include "lib_standard_app/read.h"
 #include "lib_standard_app/write.h"
 #include "swap.h"
 
+#include "apdu_constants.h"
+#include "display_variables.h"
+#include "be_operations.h"
+#include "transaction.h"
+#include "context.h"
+#include "filesystem.h"
+#include "helpers.h"
+
 #ifndef COIN_CONSENSUS_BRANCH_ID
 #define COIN_CONSENSUS_BRANCH_ID 0
 #endif 
@@ -31,6 +36,12 @@
 #define CONSENSUS_BRANCH_ID_SAPLING 0x76b809bb
 #define CONSENSUS_BRANCH_ID_ZCLASSIC 0x930b540d
 
+unsigned char const OVERWINTER_PARAM_PREVOUTS[16] = { 'Z', 'c', 'a', 's', 'h', 'P', 'r', 'e', 'v', 'o', 'u', 't', 'H', 'a', 's', 'h' };
+unsigned char const OVERWINTER_PARAM_SEQUENCE[16] = { 'Z', 'c', 'a', 's', 'h', 'S', 'e', 'q', 'u', 'e', 'n', 'c', 'H', 'a', 's', 'h' };
+unsigned char const OVERWINTER_PARAM_OUTPUTS[16] = { 'Z', 'c', 'a', 's', 'h', 'O', 'u', 't', 'p', 'u', 't', 's', 'H', 'a', 's', 'h' };
+unsigned char const OVERWINTER_PARAM_SIGHASH[16] = { 'Z', 'c', 'a', 's', 'h', 'S', 'i', 'g', 'H', 'a', 's', 'h', 0, 0, 0, 0 };
+unsigned char const OVERWINTER_NO_JOINSPLITS[32] = { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 };
+
 // Check if fOverwintered flag is set and if nVersion is >= 0x03
 #define TRUSTED_INPUT_OVERWINTER ( (COIN_KIND == COIN_KIND_ZCASH || \
                                     COIN_KIND == COIN_KIND_ZCLASSIC || \
@@ -39,59 +50,15 @@
                                     (read_u32_le(context_D.transactionVersion, 0) ^ (1<<31)) >= 0x03 \
                                 )
 
-#define DEBUG_LONG "%d"
-
-void check_transaction_available(unsigned char x) {
-    if (context_D.transactionDataRemaining < x) {
-        PRINTF("Check transaction available failed %d < %d\n", context_D.transactionDataRemaining, x);
-        THROW(EXCEPTION);
-    }
+static void check_transaction_available(unsigned char x) {
+    LEDGER_ASSERT(context_D.transactionDataRemaining >= x, "Check transaction available failed %d < %d\n", context_D.transactionDataRemaining, x);
 }
 
 #define OP_HASH160 0xA9
 #define OP_EQUAL 0x87
 #define OP_CHECKMULTISIG 0xAE
 
-unsigned char transaction_amount_add_be(unsigned char *target,
-                                        unsigned char *a,
-                                        unsigned char *b) {
-    unsigned char carry = 0;
-    unsigned char i;
-    for (i = 0; i < 8; i++) {
-        unsigned short val = a[8 - 1 - i] + b[8 - 1 - i] + (carry ? 1 : 0);
-        carry = (val > 255);
-        target[8 - 1 - i] = (val & 255);
-    }
-    return carry;
-}
-
-unsigned char transaction_amount_sub_be(unsigned char *target,
-                                        unsigned char *a,
-                                        unsigned char *b) {
-    unsigned char borrow = 0;
-    unsigned char i;
-    for (i = 0; i < 8; i++) {
-        unsigned short tmpA = a[8 - 1 - i];
-        unsigned short tmpB = b[8 - 1 - i];
-        if (borrow) {
-            if (tmpA <= tmpB) {
-                tmpA += (255 + 1) - 1;
-            } else {
-                borrow = 0;
-                tmpA--;
-            }
-        }
-        if (tmpA < tmpB) {
-            borrow = 1;
-            tmpA += 255 + 1;
-        }
-        target[8 - 1 - i] = (unsigned char)(tmpA - tmpB);
-    }
-
-    return borrow;
-}
-
-void transaction_offset(unsigned char value) {
+static void transaction_offset(unsigned char value) {
     if ((context_D.transactionHashOption & TRANSACTION_HASH_FULL) != 0) {
         PRINTF("--- ADD TO HASH FULL:\n%.*H\n", value, context_D.transactionBufferPointer);
         if (context_D.usingOverwinter) {
@@ -110,13 +77,13 @@ void transaction_offset(unsigned char value) {
     }
 }
 
-void transaction_offset_increase(unsigned char value) {
+static void transaction_offset_increase(unsigned char value) {
     transaction_offset(value);
     context_D.transactionBufferPointer += value;
     context_D.transactionDataRemaining -= value;
 }
 
-unsigned long int transaction_get_varint(void) {
+static unsigned long int transaction_get_varint(void) {
     unsigned char firstByte;
     check_transaction_available(1);
     firstByte = *context_D.transactionBufferPointer;
@@ -142,17 +109,12 @@ unsigned long int transaction_get_varint(void) {
         transaction_offset_increase(4);
         return result;
     } else {
-        PRINTF("Varint parsing failed\n");
-        THROW(INVALID_PARAMETER);
-        return 0;
+        LEDGER_ASSERT(false, "Varint parsing failed");
+        __builtin_unreachable();
     }
 }
 
 void transaction_parse(unsigned char parseMode) {
-    unsigned char optionP2SHSkip2FA =
-        ((N_btchip.bkp.config.options & OPTION_SKIP_2FA_P2SH) != 0);
-    BEGIN_TRY {
-        TRY {
             for (;;) {
                 switch (context_D.transactionContext.transactionState) {
                 case TRANSACTION_NONE: {
@@ -334,7 +296,7 @@ void transaction_parse(unsigned char parseMode) {
                     context_D.transactionContext
                         .transactionRemainingInputsOutputs =
                         transaction_get_varint();
-                    PRINTF("Number of inputs : " DEBUG_LONG "\n",context_D.transactionContext.transactionRemainingInputsOutputs);
+                    PRINTF("Number of inputs : %d\n", context_D.transactionContext.transactionRemainingInputsOutputs);
                     if (G_called_from_swap && parseMode == PARSE_MODE_SIGNATURE) {
                         // remember number of inputs to know when to exit from library
                         // we will count number of already signed inputs and compare with this value
@@ -408,14 +370,6 @@ void transaction_parse(unsigned char parseMode) {
                             PRINTF("Invalid trusted input flag\n");
                             goto fail;
                         }
-                        /*
-                        trustedInputLength =
-                        *(context_D.transactionBufferPointer + 1);
-                        if (trustedInputLength > sizeof(trustedInput)) {
-                          PRINTF("Trusted input too long\n");
-                          goto fail;
-                        }
-                        */
                         // Check TrustedInput (TI) integrity, be it a non-segwit TI or a segwit TI
                         if (trustedInputFlag) {
                             trustedInputLength = *(
@@ -514,21 +468,8 @@ void transaction_parse(unsigned char parseMode) {
                         }
                         // Handle non-segwit inputs (i.e. InputHashStart 1st APDU's P2==00 && data[0]==0x00)
                         else if (!trustedInputFlag) {
-                            if (!optionP2SHSkip2FA) {
-                                PRINTF("Untrusted input not authorized\n");
-                                goto fail;
-                            }
-                            context_D.transactionBufferPointer++;
-                            context_D.transactionDataRemaining--;
-                            check_transaction_available(
-                                36); // prevout : 32 hash + 4 index
-                            transaction_offset_increase(36);
-                            PRINTF("Marking relaxed input\n");
-                            context_D.transactionContext.relaxed = 1;
-                            /*
-                            PRINTF("Clearing P2SH consumption\n");
-                            context_D.transactionContext.consumeP2SH = 0;
-                            */
+                            PRINTF("Untrusted input not authorized\n");
+                            goto fail;
                         }
                         // Handle non-segwit TrustedInput (i.e. InputHashStart 1st APDU's P2==00 & data[0]==0x01)
                         else if (trustedInputFlag && !context_D.usingSegwit) {
@@ -543,15 +484,6 @@ void transaction_parse(unsigned char parseMode) {
                             // Update the hash with prevout data
                             savePointer =
                                 context_D.transactionBufferPointer;
-                            /*
-                            // Check if a P2SH script is used
-                            if ((trustedInput[1] & FLAG_TRUSTED_INPUT_P2SH) ==
-                            0) {
-                              PRINTF("Clearing P2SH consumption\n");
-                              context_D.transactionContext.consumeP2SH =
-                            0;
-                            }
-                            */
                             context_D.transactionBufferPointer =
                                 trustedInput + 4;
                             PRINTF("Trusted input hash\n%.*H\n",36,context_D.transactionBufferPointer);
@@ -589,7 +521,7 @@ void transaction_parse(unsigned char parseMode) {
                     // Read the script length
                     context_D.transactionContext.scriptRemaining =
                         transaction_get_varint();
-                    PRINTF("Script to read " DEBUG_LONG "\n",context_D.transactionContext.scriptRemaining);
+                    PRINTF("Script to read %d\n", context_D.transactionContext.scriptRemaining);
 
                     if ((parseMode == PARSE_MODE_SIGNATURE) &&
                         !trustedInputFlag && !context_D.usingSegwit) {
@@ -598,9 +530,7 @@ void transaction_parse(unsigned char parseMode) {
                         if (context_D.transactionContext
                                 .scriptRemaining != 0) {
                             PRINTF("Request to sign relaxed input\n");
-                            if (!optionP2SHSkip2FA) {
-                                goto fail;
-                            }
+                            goto fail;
                         }
                     }
                     // Move on
@@ -611,7 +541,7 @@ void transaction_parse(unsigned char parseMode) {
                 }
                 case TRANSACTION_INPUT_HASHING_IN_PROGRESS_INPUT_SCRIPT: {
                     unsigned char dataAvailable;
-                    PRINTF("Process input script, remaining " DEBUG_LONG "\n",context_D.transactionContext.scriptRemaining);
+                    PRINTF("Process input script, remaining %d\n", context_D.transactionContext.scriptRemaining);
                     if (context_D.transactionDataRemaining < 1) {
                         // No more data to read, ok
                         goto ok;
@@ -623,11 +553,8 @@ void transaction_parse(unsigned char parseMode) {
                         1) {
                         if (*context_D.transactionBufferPointer ==
                             OP_CHECKMULTISIG) {
-                            if (optionP2SHSkip2FA) {
-                                PRINTF("Marking P2SH consumption\n");
-                                context_D.transactionContext
-                                    .consumeP2SH = 1;
-                            }
+                            PRINTF("Marking P2SH consumption\n");
+                            context_D.transactionContext.consumeP2SH = 1;
                         } else {
                             // When using the P2SH shortcut, all inputs must use
                             // P2SH
@@ -819,7 +746,7 @@ void transaction_parse(unsigned char parseMode) {
                         transaction_get_varint();
                     context_D.transactionContext
                         .transactionCurrentInputOutput = 0;
-                    PRINTF("Number of outputs : " DEBUG_LONG "\n",
+                    PRINTF("Number of outputs : %d\n",
                         context_D.transactionContext.transactionRemainingInputsOutputs);
                     // Ready to proceed
                     context_D.transactionContext.transactionState =
@@ -857,7 +784,7 @@ void transaction_parse(unsigned char parseMode) {
                     context_D.transactionContext.scriptRemaining =
                         transaction_get_varint();
 
-                    PRINTF("Script to read " DEBUG_LONG "\n",context_D.transactionContext.scriptRemaining);
+                    PRINTF("Script to read %d\n", context_D.transactionContext.scriptRemaining);
                     // Move on
                     context_D.transactionContext.transactionState =
                         TRANSACTION_OUTPUT_HASHING_IN_PROGRESS_OUTPUT_SCRIPT;
@@ -866,21 +793,7 @@ void transaction_parse(unsigned char parseMode) {
                 }
                 case TRANSACTION_OUTPUT_HASHING_IN_PROGRESS_OUTPUT_SCRIPT: {
                     unsigned char dataAvailable;
-                    PRINTF("Process output script, remaining " DEBUG_LONG "\n",context_D.transactionContext.scriptRemaining);
-                    /*
-                    // Special check if consuming a P2SH script
-                    if (parseMode == PARSE_MODE_TRUSTED_INPUT) {
-                      // Assume the full input script is sent in a single APDU,
-                    then do the ghetto validation
-                      if ((context_D.transactionBufferPointer[0] ==
-                    OP_HASH160) &&
-                          (context_D.transactionBufferPointer[context_D.transactionDataRemaining
-                    - 1] == OP_EQUAL)) {
-                        PRINTF("Marking P2SH output\n");
-                        context_D.transactionContext.consumeP2SH = 1;
-                      }
-                    }
-                    */
+                    PRINTF("Process output script, remaining %d\n", context_D.transactionContext.scriptRemaining);
                     if (context_D.transactionDataRemaining < 1) {
                         // No more data to read, ok
                         goto ok;
@@ -986,20 +899,8 @@ void transaction_parse(unsigned char parseMode) {
             }
 
         fail:
-            PRINTF("Transaction parse - fail\n");
-            THROW(EXCEPTION);
-        ok : {}
-        }
-        CATCH_OTHER(e) {
-            PRINTF("Transaction parse - surprise fail\n");
-            context_D.transactionContext.transactionState =
-                TRANSACTION_NONE;
-            THROW(e);
-        }
-        // before the finally to restore the surrounding context if an exception
-        // is raised during finally
-        FINALLY {
-        }
-    }
-    END_TRY;
+            LEDGER_ASSERT(false, "Transaction parse - fail\n");
+        ok: 
+            return;
+
 }
diff --git a/include/btchip.h b/lib-app-bitcoin/transaction.h
similarity index 67%
rename from include/btchip.h
rename to lib-app-bitcoin/transaction.h
index f53e0e1d..fa88a83b 100644
--- a/include/btchip.h
+++ b/lib-app-bitcoin/transaction.h
@@ -15,22 +15,19 @@
 *  limitations under the License.
 ********************************************************************************/
 
-#ifndef H
+#pragma once
 
-#define H
 
-#include "config.h"
-#include "os.h"
-#include "os_io_seproxyhal.h"
+#define TRANSACTION_HASH_NONE 0x00
+#define TRANSACTION_HASH_FULL 0x01
+#define TRANSACTION_HASH_AUTHORIZATION 0x02
+#define TRANSACTION_HASH_BOTH 0x03
 
-#include "stdlib.h"
-#include "stdbool.h"
-#include "string.h"
+#define PARSE_MODE_TRUSTED_INPUT 0x01
+#define PARSE_MODE_SIGNATURE 0x02
 
-#define L_DEBUG_NOPREFIX(x)
+#define TRUSTED_INPUT_SIZE   48
+#define TRUSTED_INPUT_TOTAL_SIZE (TRUSTED_INPUT_SIZE + 8)
 
-#define SW_TECHNICAL_DETAILS(x) SW_TECHNICAL_PROBLEM
+void transaction_parse(unsigned char parseMode);
 
-#include "secure_value.h"
-
-#endif
diff --git a/src/display_variables.h b/lib-app-bitcoin/ui/display_variables.h
similarity index 87%
rename from src/display_variables.h
rename to lib-app-bitcoin/ui/display_variables.h
index c0ac6f8f..723009ab 100644
--- a/src/display_variables.h
+++ b/lib-app-bitcoin/ui/display_variables.h
@@ -1,7 +1,7 @@
-#ifndef _DISPLAY_VARIABLES_H_
-#define _DISPLAY_VARIABLES_H_
+#pragma once 
 
 #include "os.h"
+
 // A path contains 10 elements max, which max length in ascii is 1 whitespace + 10 char + optional quote "'" + "/" + \0"
 #define MAX_DERIV_PATH_ASCII_LENGTH 1 + 10*(10+2) + 1
 #define MAX_CHAR_PER_LINE 25
@@ -26,8 +26,8 @@ union display_variables {
         // of
 
         char fullAddress[65]; // the address
-        char fullAmount[20];  // full amount
-        char feesAmount[20];  // fees
+        char fullAmount[28];  // full amount
+        char feesAmount[28];  // fees
     } tmp;
 
     struct {
@@ -38,5 +38,3 @@ union display_variables {
 };
 
 extern union display_variables vars;
-
-#endif
diff --git a/src/bagl_extensions.h b/lib-app-bitcoin/ui/extensions.h
similarity index 57%
rename from src/bagl_extensions.h
rename to lib-app-bitcoin/ui/extensions.h
index c3029694..7aed64c9 100644
--- a/src/bagl_extensions.h
+++ b/lib-app-bitcoin/ui/extensions.h
@@ -15,44 +15,40 @@
 *  limitations under the License.
 ********************************************************************************/
 
-#ifndef _BAGL_H_
-#define _BAGL_H_
+#pragma once 
 
 // btchip asking the per-output UI
-unsigned int bagl_confirm_single_output(void);
+unsigned int confirm_single_output(void);
 
 // btchip display token
-void bagl_display_token(void);
+void display_token(void);
 
 // btchip finalizing the transaction
-unsigned int bagl_finalize_tx(void);
+unsigned int finalize_tx(void);
 
 // UI response to btchip to finish the exchange
-unsigned char bagl_user_action(unsigned char confirming);
+unsigned char user_action(unsigned char confirming);
 
 // request the UI to redisplay the idle screen
-void bagl_idle(void);
+void idle(void);
 
 // btchip asking message signing confirmation
-void bagl_confirm_message_signature(void);
+void confirm_message_signature(void);
 
 // UI response to message signature
-void bagl_user_action_message_signing(unsigned char confirming);
+int user_action_message_signing(unsigned char confirming);
 
 // Public key display
-uint8_t set_key_path_to_display(unsigned char* keyPath);
-void bagl_display_public_key(uint8_t is_derivation_path_unusual);
-void bagl_user_action_display(unsigned char confirming);
+uint8_t set_key_path_to_display(const unsigned char* keyPath);
+void display_public_key(uint8_t is_derivation_path_unusual);
+int user_action_display(unsigned char confirming);
 
-void bagl_request_pubkey_approval(void);
-void bagl_request_change_path_approval(unsigned char* change_path);
+void request_pubkey_approval(void);
+void request_change_path_approval(unsigned char* change_path);
 
 // UI to confirm processing of tx with segwit inputs
-void bagl_request_segwit_input_approval(void);
+void request_segwit_input_approval(void);
 
 // UI to confirm signing path
-void bagl_request_sign_path_approval(unsigned char *derivation_path);
-void bagl_user_action_signtx(unsigned char confirming, unsigned char direct);
-
-
-#endif /* _BAGL_H_ */
+void request_sign_path_approval(unsigned char* change_path);
+int user_action_signtx(unsigned char confirming, unsigned char direct);
diff --git a/lib-app-bitcoin/ui/main_ui.c b/lib-app-bitcoin/ui/main_ui.c
new file mode 100644
index 00000000..850e6016
--- /dev/null
+++ b/lib-app-bitcoin/ui/main_ui.c
@@ -0,0 +1,311 @@
+/*******************************************************************************
+*   Ledger App - Bitcoin Wallet
+*   (c) 2016-2019 Ledger
+*
+*  Licensed under the Apache License, Version 2.0 (the "License");
+*  you may not use this file except in compliance with the License.
+*  You may obtain a copy of the License at
+*
+*      http://www.apache.org/licenses/LICENSE-2.0
+*
+*  Unless required by applicable law or agreed to in writing, software
+*  distributed under the License is distributed on an "AS IS" BASIS,
+*  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+*  See the License for the specific language governing permissions and
+*  limitations under the License.
+********************************************************************************/
+#include "os.h"
+#include "cx.h"
+#include "format.h"
+#include "read.h"
+#include "write.h"
+#include "bip32.h"
+#include "swap.h"
+#include "string.h"
+
+
+#include "context.h"
+#include "helpers.h"
+#include "customizable_helpers.h"
+#include "customizable_ui.h"
+#include "extensions.h"
+#include "display_utils.h"
+#include "ux.h"
+#include "display_variables.h"
+#include "swap_lib_calls.h"
+#include "handle_swap_sign_transaction.h"
+#include "handle_get_printable_amount.h"
+#include "handle_check_address.h"
+#include "ui.h"
+#include "be_operations.h"
+
+#define OMNI_ASSETID 1
+#define MAIDSAFE_ASSETID 3
+#define USDT_ASSETID 31
+
+static uint8_t check_fee_swap() {
+    unsigned char fees[8];
+    unsigned char borrow;
+
+    borrow = transaction_amount_sub_be(
+            fees, context_D.transactionContext.transactionAmount,
+            context_D.totalOutputAmount);
+    if ((borrow != 0) || (memcmp(fees, vars.swap_data.fees, 8) != 0))
+        return 0;
+    context_D.transactionContext.firstSigned = 0;
+
+    if (context_D.usingSegwit &&  !context_D.segwitParsedOnce) {
+        // This input cannot be signed when using segwit - just restart.
+        context_D.segwitParsedOnce = 1;
+        PRINTF("Segwit parsed once\n");
+        context_D.transactionContext.transactionState =
+        TRANSACTION_NONE;
+    } else {
+        context_D.transactionContext.transactionState =
+        TRANSACTION_SIGN_READY;
+    }
+    context_D.sw = 0x9000;
+    context_D.outLength = 0;
+    G_io_apdu_buffer[context_D.outLength++] = 0x90;
+    G_io_apdu_buffer[context_D.outLength++] = 0x00;
+
+    return 1;
+}
+
+#define OMNI_ASSETID 1
+#define MAIDSAFE_ASSETID 3
+#define USDT_ASSETID 31
+
+static void prepare_single_output(void) {
+    // TODO : special display for OP_RETURN
+    unsigned char amount[8];
+    unsigned int offset = 0;
+    char tmp[80] = {0};
+
+    swap_bytes(amount, context_D.currentOutput + offset, 8);
+    offset += 8;
+
+    get_address_from_output_script(context_D.currentOutput + offset,  sizeof(context_D.currentOutput) - offset, tmp, sizeof(tmp));
+    strncpy(vars.tmp.fullAddress, tmp, sizeof(vars.tmp.fullAddress) - 1);
+
+    // Prepare amount
+
+    // Handle Omni simple send
+    if ((context_D.currentOutput[offset + 2] == 0x14) &&
+        (memcmp(context_D.currentOutput + offset + 3, "omni", 4) == 0) &&
+        (memcmp(context_D.currentOutput + offset + 3 + 4, "\0\0\0\0", 4) == 0)) {
+            uint32_t omniAssetId = read_u32_be(context_D.currentOutput, offset + 3 + 4 + 4);
+            switch(omniAssetId) {
+                case OMNI_ASSETID:
+                    strcpy(vars.tmp.fullAmount, "OMNI ");
+                    break;
+                case USDT_ASSETID:
+                    strcpy(vars.tmp.fullAmount, "USDT ");
+                    break;
+                case MAIDSAFE_ASSETID:
+                    strcpy(vars.tmp.fullAmount, "MAID ");
+                    break;
+                default:
+                    snprintf(vars.tmp.fullAmount, sizeof(vars.tmp.fullAmount), "OMNI asset %d ", omniAssetId);
+                    break;
+            }
+            format_sats_amount(vars.tmp.fullAmount,
+                    (uint64_t) read_u64_be(context_D.currentOutput, offset + 3 + 4 + 4 + 4), // Cast prevents weird compilo bug
+                    vars.tmp.fullAmount);
+    }
+    else {
+        format_sats_amount(COIN_COINID_SHORT,
+                (uint64_t)read_u64_be(amount, 0),  // Cast prevents weird compilo bug
+                vars.tmp.fullAmount);
+    }
+}
+
+static uint8_t prepare_message_signature(void) {
+    uint8_t buffer[32];
+
+    if (cx_hash_no_throw(&context_D.transactionHashAuthorization.header, CX_LAST,
+            (uint8_t*)vars.tmp.fullAmount, 0, buffer, 32)) {
+        return 0;
+    }
+
+    format_hex((const uint8_t*) buffer, sizeof(buffer), vars.tmp.fullAddress, sizeof(vars.tmp.fullAddress));
+
+    return 1;
+}
+
+
+extern int handle_output_state(unsigned int* processed);
+extern void hash_input_finalize_full_reset(void);
+
+// Analog of confirm_single_output to work
+// in silent mode, when called from SWAP app
+unsigned int silent_confirm_single_output() {
+    char tmp[80] = {0};
+    unsigned char amount[8];
+    while (true) {
+        // in swap operation we can only have 1 "external" output
+        if (vars.swap_data.was_address_checked) {
+            PRINTF("Address was already checked\n");
+            return 0;
+        }
+        vars.swap_data.was_address_checked = 1;
+        // check amount
+        swap_bytes(amount, context_D.currentOutput, 8);
+        if (memcmp(amount, vars.swap_data.amount, 8) != 0) {
+            PRINTF("Amount not matched\n");
+            return 0;
+        }
+        get_address_from_output_script(context_D.currentOutput + 8, sizeof(context_D.currentOutput) - 8, tmp, sizeof(tmp));
+        if (strcmp(tmp, vars.swap_data.destination_address) != 0) {
+            PRINTF("Address not matched\n");
+            return 0;
+        }
+
+        // Check if all inputs have been confirmed
+
+        if (context_D.outputParsingState ==
+            OUTPUT_PARSING_OUTPUT) {
+            context_D.remainingOutputs--;
+            if (context_D.remainingOutputs == 0)
+                break;
+        }
+
+        memmove(context_D.currentOutput,
+                    context_D.currentOutput +
+                        context_D.discardSize,
+                    context_D.currentOutputOffset -
+                        context_D.discardSize);
+        context_D.currentOutputOffset -= context_D.discardSize;
+        unsigned int processed = true;
+        while (processed == 1) {
+            if (handle_output_state(&processed)) {
+                PRINTF("Error in handle output state \n");
+                return 0;
+            }
+        }
+
+        if (processed != 2) {
+            // Out of data to process, wait for the next call
+            break;
+        }
+    }
+
+    if ((context_D.outputParsingState == OUTPUT_PARSING_OUTPUT) &&
+        (context_D.remainingOutputs == 0)) {
+        context_D.outputParsingState = OUTPUT_FINALIZE_TX;
+        // check fees
+        unsigned char fees[8];
+
+        if ((transaction_amount_sub_be(fees,
+                                       context_D.transactionContext.transactionAmount,
+                                       context_D.totalOutputAmount) != 0) ||
+            (memcmp(fees, vars.swap_data.fees, 8) != 0)) {
+            PRINTF("Fees is not matched\n");
+            return 0;
+        }
+    }
+
+    if (context_D.outputParsingState == OUTPUT_FINALIZE_TX) {
+        context_D.transactionContext.firstSigned = 0;
+
+        if (context_D.usingSegwit &&
+            !context_D.segwitParsedOnce) {
+            // This input cannot be signed when using segwit - just restart.
+            context_D.segwitParsedOnce = 1;
+            PRINTF("Segwit parsed once\n");
+            context_D.transactionContext.transactionState =
+                TRANSACTION_NONE;
+        } else {
+            context_D.transactionContext.transactionState =
+                TRANSACTION_SIGN_READY;
+        }
+    }
+    if (context_D.outputParsingState == OUTPUT_FINALIZE_TX) {
+        // we've finished the processing of the input
+        hash_input_finalize_full_reset();
+    }
+
+    return 1;
+}
+
+unsigned int confirm_single_output(void) {
+    if (G_called_from_swap) {
+        if (silent_confirm_single_output()) {
+            return 2;
+        }
+        return 0;
+    }
+    prepare_single_output();
+
+    ui_confirm_single_flow();
+    return 1;
+}
+
+unsigned int finalize_tx(void) {
+    if (G_called_from_swap) {
+        if (check_fee_swap()) {
+            return 2;
+        }
+    }
+
+    if (!prepare_fees()) {
+        return 0;
+    }
+
+    ui_finalize_flow();
+    return 1;
+}
+
+void confirm_message_signature(void) {
+    if (!prepare_message_signature()) {
+        return;
+    }
+
+    ui_sign_message_flow();
+}
+
+uint8_t set_key_path_to_display(const unsigned char* keyPath) {
+    format_path(keyPath, vars.tmp_warning.derivation_path, sizeof(vars.tmp_warning.derivation_path));
+    return bip44_derivation_guard(keyPath, false);
+}
+
+void display_public_key(uint8_t is_derivation_path_unusual) {
+    // append a white space at the end of the address to avoid glitch on nano S
+    strlcat((char *)G_io_apdu_buffer + 200, " ", sizeof(G_io_apdu_buffer) - 200);
+
+    if (is_derivation_path_unusual) {
+        ui_display_public_with_warning_flow();
+    }
+    else {
+        ui_display_public_flow();
+    }
+}
+
+void display_token(void)
+{
+    ui_display_token_flow();
+}
+
+void request_pubkey_approval(void)
+{
+    ui_request_pubkey_approval_flow();
+}
+
+void request_change_path_approval(unsigned char* change_path)
+{
+    format_path(change_path, vars.tmp_warning.derivation_path, sizeof(vars.tmp_warning.derivation_path));
+    ui_request_change_path_approval_flow();
+}
+
+void request_sign_path_approval(unsigned char* change_path)
+{
+    format_path(change_path, vars.tmp_warning.derivation_path, sizeof(vars.tmp_warning.derivation_path));
+    ui_request_sign_path_approval_flow();
+}
+
+void request_segwit_input_approval(void)
+{
+    ui_request_segwit_input_approval_flow();
+}
+
+
diff --git a/src/ui.h b/lib-app-bitcoin/ui/ui.h
similarity index 100%
rename from src/ui.h
rename to lib-app-bitcoin/ui/ui.h
diff --git a/src/ui_bagl.c b/lib-app-bitcoin/ui/ui_bagl.c
similarity index 97%
rename from src/ui_bagl.c
rename to lib-app-bitcoin/ui/ui_bagl.c
index 6c4ee66e..a7e0e1b8 100644
--- a/src/ui_bagl.c
+++ b/lib-app-bitcoin/ui/ui_bagl.c
@@ -18,17 +18,18 @@
 #ifdef HAVE_BAGL
 //////////////////////////////////////////////////////////////////////
 #include "display_variables.h"
-#include "internal.h"
+#include "transaction.h"
+#include "context.h"
 #include "ui.h"
 
-#include "bagl_extensions.h"
+#include "extensions.h"
 
 bagl_element_t tmp_element;
 
 static unsigned int io_seproxyhal_touch_verify_cancel(const bagl_element_t *e) {
   UNUSED(e);
   // user denied the transaction, tell the USB side
-  if (!bagl_user_action(0)) {
+  if (!user_action(0)) {
     // redraw ui
     ui_idle_flow();
   }
@@ -38,7 +39,7 @@ static unsigned int io_seproxyhal_touch_verify_cancel(const bagl_element_t *e) {
 static unsigned int io_seproxyhal_touch_verify_ok(const bagl_element_t *e) {
   UNUSED(e);
   // user accepted the transaction, tell the USB side
-  if (!bagl_user_action(1)) {
+  if (!user_action(1)) {
     // redraw ui
     ui_idle_flow();
   }
@@ -49,7 +50,7 @@ static unsigned int
 io_seproxyhal_touch_message_signature_verify_cancel(const bagl_element_t *e) {
   UNUSED(e);
   // user denied the transaction, tell the USB side
-  bagl_user_action_message_signing(0);
+  user_action_message_signing(0);
   // redraw ui
   ui_idle_flow();
   return 0; // DO NOT REDRAW THE BUTTON
@@ -59,7 +60,7 @@ static unsigned int
 io_seproxyhal_touch_message_signature_verify_ok(const bagl_element_t *e) {
   UNUSED(e);
   // user accepted the transaction, tell the USB side
-  bagl_user_action_message_signing(1);
+  user_action_message_signing(1);
   // redraw ui
   ui_idle_flow();
   return 0; // DO NOT REDRAW THE BUTTON
@@ -69,7 +70,7 @@ static unsigned int
 io_seproxyhal_touch_display_cancel(const bagl_element_t *e) {
   UNUSED(e);
   // user denied the transaction, tell the USB side
-  bagl_user_action_display(0);
+  user_action_display(0);
   // redraw ui
   ui_idle_flow();
   return 0; // DO NOT REDRAW THE BUTTON
@@ -78,16 +79,15 @@ io_seproxyhal_touch_display_cancel(const bagl_element_t *e) {
 static unsigned int io_seproxyhal_touch_display_ok(const bagl_element_t *e) {
   UNUSED(e);
   // user accepted the transaction, tell the USB side
-  bagl_user_action_display(1);
   // redraw ui
   ui_idle_flow();
-  return 0; // DO NOT REDRAW THE BUTTON
+  return user_action_display(1);
 }
 
 static unsigned int io_seproxyhal_touch_sign_cancel(const bagl_element_t *e) {
   UNUSED(e);
   // user denied the transaction, tell the USB side
-  bagl_user_action_signtx(0, 0);
+  user_action_signtx(0, 0);
   // redraw ui
   ui_idle_flow();
   return 0; // DO NOT REDRAW THE BUTTON
@@ -96,7 +96,7 @@ static unsigned int io_seproxyhal_touch_sign_cancel(const bagl_element_t *e) {
 static unsigned int io_seproxyhal_touch_sign_ok(const bagl_element_t *e) {
   UNUSED(e);
   // user accepted the transaction, tell the USB side
-  bagl_user_action_signtx(1, 0);
+  user_action_signtx(1, 0);
   // redraw ui
   ui_idle_flow();
   return 0; // DO NOT REDRAW THE BUTTON
@@ -107,8 +107,7 @@ void io_seproxyhal_display(const bagl_element_t *element) {
     io_seproxyhal_display_default((bagl_element_t *)element);
   }
 }
-
-//////////////////////////////////////////////////////////////////////
+//////////////////////////////////////////////////////////////////////////////////////
 UX_STEP_NOCB(ux_idle_flow_1_step, nn,
              {
                  "Application",
diff --git a/src/ui_menu_nbgl.c b/lib-app-bitcoin/ui/ui_menu_nbgl.c
similarity index 97%
rename from src/ui_menu_nbgl.c
rename to lib-app-bitcoin/ui/ui_menu_nbgl.c
index 20b865e6..de876fc7 100644
--- a/src/ui_menu_nbgl.c
+++ b/lib-app-bitcoin/ui/ui_menu_nbgl.c
@@ -17,10 +17,9 @@
 
 #ifdef HAVE_NBGL
 #include "display_variables.h"
-#include "internal.h"
 #include "ui.h"
 
-#include "bagl_extensions.h"
+#include "extensions.h"
 #include "nbgl_use_case.h"
 
 #define NB_INFO_FIELDS 2
diff --git a/src/ui_nbgl.c b/lib-app-bitcoin/ui/ui_nbgl.c
similarity index 97%
rename from src/ui_nbgl.c
rename to lib-app-bitcoin/ui/ui_nbgl.c
index ee41f795..642b8747 100644
--- a/src/ui_nbgl.c
+++ b/lib-app-bitcoin/ui/ui_nbgl.c
@@ -19,9 +19,9 @@
 #include "ui.h"
 #include "nbgl_use_case.h"
 #include "display_variables.h"
-#include "internal.h"
+#include "context.h"
 
-#include "bagl_extensions.h"
+#include "extensions.h"
 
 typedef enum { 
     MESSAGE_TYPE, 
@@ -55,55 +55,55 @@ static UiContext_t uiContext = {.transaction_prompt_done = 0};
 
 // User action callbacks
 static void approved_user_action_callback(void) {
-  if (!bagl_user_action(1)) {
+  if (!user_action(1)) {
     ui_idle_flow();
   }
 }
 
 static void approved_user_action_processing_callback(void) {
-  if (!bagl_user_action(1)) {
+  if (!user_action(1)) {
     nbgl_useCaseSpinner("Processing");
   }
 }
 
 static void abandon_user_action_callback(void) {
-  if (!bagl_user_action(0)) {
+  if (!user_action(0)) {
     ui_idle_flow();
   }
 }
 
 static void approved_user_action_message_signing_callback(void) {
-  bagl_user_action_message_signing(1);
+  user_action_message_signing(1);
   ui_idle_flow();
 }
 
 static void abandon_user_action_message_signing_callback(void) {
-  bagl_user_action_message_signing(0);
+  user_action_message_signing(0);
   ui_idle_flow();
 }
 
 static void approved_user_action_display_processing_callback(void) {
-  bagl_user_action_display(1);
+  user_action_display(1);
   nbgl_useCaseSpinner("Processing");
 }
 
 static void approved_user_action_display_callback(void) {
-  bagl_user_action_display(1);
+  user_action_display(1);
   ui_idle_flow();
 }
 
 static void abandon_user_action_display_callback(void) {
-  bagl_user_action_display(0);
+  user_action_display(0);
   ui_idle_flow();
 }
 
 static void approved_user_action_signtx_callback(void) {
-  bagl_user_action_signtx(1, 0);
+  user_action_signtx(1, 0);
   ui_idle_flow();
 }
 
 static void abandon_user_action_signtx_callback(void) {
-  bagl_user_action_signtx(0, 0);
+  user_action_signtx(0, 0);
   ui_idle_flow();
 }
 
@@ -479,7 +479,7 @@ static void prompt_public_key(bool warning) {
   }
 }
 
-static void display_public_key(bool warning) {
+static void display_show_public_key(bool warning) {
   uiContext.abandon_status = "Address verification\ncancelled";
   uiContext.approved_status = "ADDRESS\nVERIFIED";
   uiContext.prompt_cancel_message = "Reject\nAddress?";
@@ -507,11 +507,11 @@ static void display_public_key(bool warning) {
 }
 
 void ui_display_public_with_warning_flow(void) {
-  display_public_key(true);
+  display_show_public_key(true);
 }
 
 void ui_display_public_flow(void) {
-  display_public_key(false);
+  display_show_public_key(false);
 }
 
 void ui_transaction_finish(void) {
diff --git a/lib-app-bitcoin/utils/be_operations.c b/lib-app-bitcoin/utils/be_operations.c
new file mode 100644
index 00000000..43c916e3
--- /dev/null
+++ b/lib-app-bitcoin/utils/be_operations.c
@@ -0,0 +1,42 @@
+#include "be_operations.h"
+
+unsigned char transaction_amount_add_be(unsigned char *target,
+                                        unsigned char *a,
+                                        unsigned char *b) {
+    unsigned char carry = 0;
+    unsigned char i;
+    for (i = 0; i < 8; i++) {
+        unsigned short val = a[8 - 1 - i] + b[8 - 1 - i] + (carry ? 1 : 0);
+        carry = (val > 255);
+        target[8 - 1 - i] = (val & 255);
+    }
+    return carry;
+}
+
+unsigned char transaction_amount_sub_be(unsigned char *target,
+                                        unsigned char *a,
+                                        unsigned char *b) {
+    unsigned char borrow = 0;
+    unsigned char i;
+    for (i = 0; i < 8; i++) {
+        unsigned short tmpA = a[8 - 1 - i];
+        unsigned short tmpB = b[8 - 1 - i];
+        if (borrow) {
+            if (tmpA <= tmpB) {
+                tmpA += (255 + 1) - 1;
+            } else {
+                borrow = 0;
+                tmpA--;
+            }
+        }
+        if (tmpA < tmpB) {
+            borrow = 1;
+            tmpA += 255 + 1;
+        }
+        target[8 - 1 - i] = (unsigned char)(tmpA - tmpB);
+    }
+
+    return borrow;
+}
+
+
diff --git a/src/transaction.h b/lib-app-bitcoin/utils/be_operations.h
similarity index 71%
rename from src/transaction.h
rename to lib-app-bitcoin/utils/be_operations.h
index 01b50048..8dc7a9a2 100644
--- a/src/transaction.h
+++ b/lib-app-bitcoin/utils/be_operations.h
@@ -15,23 +15,7 @@
 *  limitations under the License.
 ********************************************************************************/
 
-#ifndef _TRANSACTION_H_
-#define _TRANSACTION_H_
-
-#include "secure_value.h"
-
-#define TRANSACTION_HASH_NONE 0x00
-#define TRANSACTION_HASH_FULL 0x01
-#define TRANSACTION_HASH_AUTHORIZATION 0x02
-#define TRANSACTION_HASH_BOTH 0x03
-
-#define PARSE_MODE_TRUSTED_INPUT 0x01
-#define PARSE_MODE_SIGNATURE 0x02
-
-#define TRUSTED_INPUT_SIZE   48
-#define TRUSTED_INPUT_TOTAL_SIZE (TRUSTED_INPUT_SIZE + 8)
-
-void transaction_parse(unsigned char parseMode);
+#pragma once
 
 // target = a + b
 unsigned char transaction_amount_add_be(unsigned char *target,
@@ -42,5 +26,3 @@ unsigned char transaction_amount_add_be(unsigned char *target,
 unsigned char transaction_amount_sub_be(unsigned char *target,
                                         unsigned char *a,
                                         unsigned char *b);
-
-#endif /* _TRANSACTION_H_ */
diff --git a/src/cashaddr.c b/lib-app-bitcoin/utils/cashaddr.c
similarity index 100%
rename from src/cashaddr.c
rename to lib-app-bitcoin/utils/cashaddr.c
diff --git a/src/cashaddr.h b/lib-app-bitcoin/utils/cashaddr.h
similarity index 100%
rename from src/cashaddr.h
rename to lib-app-bitcoin/utils/cashaddr.h
diff --git a/src/segwit_addr.c b/lib-app-bitcoin/utils/segwit_addr.c
similarity index 100%
rename from src/segwit_addr.c
rename to lib-app-bitcoin/utils/segwit_addr.c
diff --git a/src/segwit_addr.h b/lib-app-bitcoin/utils/segwit_addr.h
similarity index 100%
rename from src/segwit_addr.h
rename to lib-app-bitcoin/utils/segwit_addr.h
diff --git a/src/apdu_get_wallet_public_key.h b/src/apdu_get_wallet_public_key.h
deleted file mode 100644
index 429076d6..00000000
--- a/src/apdu_get_wallet_public_key.h
+++ /dev/null
@@ -1,13 +0,0 @@
-#ifndef _APDU_GET_WALLET_PUBLIC_KEY_H_
-#define _APDU_GET_WALLET_PUBLIC_KEY_H_
-
-#define P1_NO_DISPLAY 0x00
-#define P1_DISPLAY 0x01
-#define P1_REQUEST_TOKEN 0x02
-
-#define P2_LEGACY 0x00
-#define P2_SEGWIT 0x01
-#define P2_NATIVE_SEGWIT 0x02
-#define P2_CASHADDR 0x03
-
-#endif //_APDU_GET_WALLET_PUBLIC_KEY_H_
\ No newline at end of file
diff --git a/src/bcd.c b/src/bcd.c
deleted file mode 100644
index a7878d0b..00000000
--- a/src/bcd.c
+++ /dev/null
@@ -1,103 +0,0 @@
-/*******************************************************************************
-*   Ledger App - Bitcoin Wallet
-*   (c) 2016-2019 Ledger
-*
-*  Licensed under the Apache License, Version 2.0 (the "License");
-*  you may not use this file except in compliance with the License.
-*  You may obtain a copy of the License at
-*
-*      http://www.apache.org/licenses/LICENSE-2.0
-*
-*  Unless required by applicable law or agreed to in writing, software
-*  distributed under the License is distributed on an "AS IS" BASIS,
-*  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-*  See the License for the specific language governing permissions and
-*  limitations under the License.
-********************************************************************************/
-
-#include "internal.h"
-
-#define SCRATCH_SIZE 21
-
-unsigned char
-convert_hex_amount_to_displayable_no_globals(unsigned char *amount, unsigned int config_flag, unsigned char* out) {
-    unsigned char LOOP1;
-    unsigned char LOOP2;
-    if (!(config_flag & FLAG_PEERCOIN_UNITS)) {
-        LOOP1 = 13;
-        LOOP2 = 8;
-    } else {
-        LOOP1 = 15;
-        LOOP2 = 6;
-    }
-    unsigned short scratch[SCRATCH_SIZE];
-    unsigned char offset = 0;
-    unsigned char nonZero = 0;
-    unsigned char i;
-    unsigned char targetOffset = 0;
-    unsigned char workOffset;
-    unsigned char j;
-    unsigned char nscratch = SCRATCH_SIZE;
-    unsigned char smin = nscratch - 2;
-    unsigned char comma = 0;
-
-    for (i = 0; i < SCRATCH_SIZE; i++) {
-        scratch[i] = 0;
-    }
-    for (i = 0; i < 8; i++) {
-        for (j = 0; j < 8; j++) {
-            unsigned char k;
-            unsigned short shifted_in =
-                (((amount[i] & 0xff) & ((1 << (7 - j)))) != 0) ? (short)1
-                                                               : (short)0;
-            for (k = smin; k < nscratch; k++) {
-                scratch[k] += ((scratch[k] >= 5) ? 3 : 0);
-            }
-            if (scratch[smin] >= 8) {
-                smin -= 1;
-            }
-            for (k = smin; k < nscratch - 1; k++) {
-                scratch[k] =
-                    ((scratch[k] << 1) & 0xF) | ((scratch[k + 1] >= 8) ? 1 : 0);
-            }
-            scratch[nscratch - 1] = ((scratch[nscratch - 1] << 1) & 0x0F) |
-                                    (shifted_in == 1 ? 1 : 0);
-        }
-    }
-
-    for (i = 0; i < LOOP1; i++) {
-        if (!nonZero && (scratch[offset] == 0)) {
-            offset++;
-        } else {
-            nonZero = 1;
-            out[targetOffset++] = scratch[offset++] + '0';
-        }
-    }
-    if (targetOffset == 0) {
-        out[targetOffset++] = '0';
-    }
-    workOffset = offset;
-    for (i = 0; i < LOOP2; i++) {
-        unsigned char allZero = 1;
-        for (j = i; j < LOOP2; j++) {
-            if (scratch[workOffset + j] != 0) {
-                allZero = 0;
-                break;
-            }
-        }
-        if (allZero) {
-            break;
-        }
-        if (!comma) {
-            out[targetOffset++] = '.';
-            comma = 1;
-        }
-        out[targetOffset++] = scratch[offset++] + '0';
-    }
-    return targetOffset;
-}
-
-unsigned char
-convert_hex_amount_to_displayable(unsigned char *amount) {
-    return convert_hex_amount_to_displayable_no_globals(amount, COIN_FLAGS, context_D.tmp);
-}
diff --git a/src/bip32_path.c b/src/bip32_path.c
deleted file mode 100644
index 8be5d787..00000000
--- a/src/bip32_path.c
+++ /dev/null
@@ -1,16 +0,0 @@
-#include "lib_standard_app/read.h"
-#include "bip32_path.h"
-#include "helpers.h"
-
-bool parse_serialized_path(bip32_path_t* path, unsigned char* serialized_path, unsigned char serialized_path_length) {
-    if (serialized_path_length < 1 ||
-        serialized_path[0] > MAX_BIP32_PATH ||
-        serialized_path[0] * 4 + 1 > serialized_path_length)
-        return false;
-    path->length = serialized_path[0];
-    serialized_path++;
-    for (int i = 0; i < path->length; i += 1, serialized_path += 4) {
-        path->path[i] = read_u32_be(serialized_path, 0);
-    }
-    return true;
-}
diff --git a/src/bip32_path.h b/src/bip32_path.h
deleted file mode 100644
index 819ea8c9..00000000
--- a/src/bip32_path.h
+++ /dev/null
@@ -1,16 +0,0 @@
-#ifndef _BIP32_PATH_H_
-#define _BIP32_PATH_H_
-
-#include "stdbool.h"
-
-#define MAX_BIP32_PATH 10
-#define MAX_BIP32_PATH_LENGTH (4 * MAX_BIP32_PATH) + 1
-
-typedef struct bip32_path {
-    unsigned char length;
-    unsigned int path[MAX_BIP32_PATH];
-} bip32_path_t;
-
-bool parse_serialized_path(bip32_path_t* path, unsigned char* serialized_path, unsigned char serialized_path_length);
-
-#endif
\ No newline at end of file
diff --git a/src/btchip.c b/src/btchip.c
deleted file mode 100644
index 2d65d16f..00000000
--- a/src/btchip.c
+++ /dev/null
@@ -1,606 +0,0 @@
-/*******************************************************************************
-*   Ledger App - Bitcoin Wallet
-*   (c) 2016-2019 Ledger
-*
-*  Licensed under the Apache License, Version 2.0 (the "License");
-*  you may not use this file except in compliance with the License.
-*  You may obtain a copy of the License at
-*
-*      http://www.apache.org/licenses/LICENSE-2.0
-*
-*  Unless required by applicable law or agreed to in writing, software
-*  distributed under the License is distributed on an "AS IS" BASIS,
-*  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-*  See the License for the specific language governing permissions and
-*  limitations under the License.
-********************************************************************************/
-#include "os.h"
-#include "cx.h"
-
-#include "string.h"
-
-#include "internal.h"
-
-#include "bagl_extensions.h"
-
-#include "segwit_addr.h"
-#include "cashaddr.h"
-
-#include "ux.h"
-#include "display_variables.h"
-#include "swap_lib_calls.h"
-
-#include "handle_swap_sign_transaction.h"
-#include "handle_get_printable_amount.h"
-#include "handle_check_address.h"
-#include "ui.h"
-#include "lib_standard_app/format.h"
-#include "read.h"
-#include "write.h"
-#include "bip32.h"
-#include "swap.h"
-
-unsigned short io_exchange_al(unsigned char channel, unsigned short tx_len) {
-    switch (channel & ~(IO_FLAGS)) {
-    case CHANNEL_KEYBOARD:
-        break;
-
-    // multiplexed io exchange over a SPI channel and TLV encapsulated protocol
-    case CHANNEL_SPI:
-        if (tx_len) {
-            io_seproxyhal_spi_send(G_io_apdu_buffer, tx_len);
-
-            if (channel & IO_RESET_AFTER_REPLIED) {
-                reset();
-            }
-            return 0; // nothing received from the master so far (it's a tx
-                      // transaction)
-        } else {
-            return io_seproxyhal_spi_recv(G_io_apdu_buffer,
-                                          sizeof(G_io_apdu_buffer), 0);
-        }
-
-    default:
-        THROW(INVALID_PARAMETER);
-    }
-    return 0;
-}
-
-unsigned char io_event(unsigned char channel) {
-    UNUSED(channel);
-    // nothing done with the event, throw an error on the transport layer if
-    // needed
-
-    // can't have more than one tag in the reply, not supported yet.
-    switch (G_io_seproxyhal_spi_buffer[0]) {
-#ifdef HAVE_NBGL
-    case SEPROXYHAL_TAG_FINGER_EVENT:
-        UX_FINGER_EVENT(G_io_seproxyhal_spi_buffer);
-        break;
-#endif  // HAVE_NBGL
-
-    case SEPROXYHAL_TAG_BUTTON_PUSH_EVENT:
-#ifdef HAVE_BAGL
-        UX_BUTTON_PUSH_EVENT(G_io_seproxyhal_spi_buffer);
-#endif // HAVE_BAGL
-        break;
-
-    case SEPROXYHAL_TAG_STATUS_EVENT:
-        if (G_io_apdu_media == IO_APDU_MEDIA_USB_HID &&
-            !(U4BE(G_io_seproxyhal_spi_buffer, 3) &
-              SEPROXYHAL_TAG_STATUS_EVENT_FLAG_USB_POWERED)) {
-            THROW(EXCEPTION_IO_RESET);
-        }
-        __attribute__((fallthrough));
-    default:
-        UX_DEFAULT_EVENT();
-        break;
-
-    case SEPROXYHAL_TAG_DISPLAY_PROCESSED_EVENT:
-#ifdef HAVE_BAGL
-        UX_DISPLAYED_EVENT({});
-#endif // HAVE_BAGL
-#ifdef HAVE_NBGL
-        UX_DEFAULT_EVENT();
-#endif // HAVE_NBGL
-        break;
-
-    case SEPROXYHAL_TAG_TICKER_EVENT:
-        // TODO: found less hacky way to exit library after sending response
-        // this mechanism is used for Swap/Exchange functionality
-        // when application is in silent mode, and should return to caller,
-        // after responding some APDUs
-        UX_TICKER_EVENT(G_io_seproxyhal_spi_buffer, {});
-        break;
-    }
-
-    // close the event if not done previously (by a display or whatever)
-    if (!io_seproxyhal_spi_is_status_sent()) {
-        io_seproxyhal_general_status();
-    }
-
-    // command has been processed, DO NOT reset the current APDU transport
-    return 1;
-}
-
-uint8_t check_fee_swap() {
-    unsigned char fees[8];
-    unsigned char borrow;
-
-    borrow = transaction_amount_sub_be(
-            fees, context_D.transactionContext.transactionAmount,
-            context_D.totalOutputAmount);
-    if ((borrow != 0) || (memcmp(fees, vars.swap_data.fees, 8) != 0))
-        return 0;
-    context_D.transactionContext.firstSigned = 0;
-
-    if (context_D.usingSegwit &&  !context_D.segwitParsedOnce) {
-        // This input cannot be signed when using segwit - just restart.
-        context_D.segwitParsedOnce = 1;
-        PRINTF("Segwit parsed once\n");
-        context_D.transactionContext.transactionState =
-        TRANSACTION_NONE;
-    } else {
-        context_D.transactionContext.transactionState =
-        TRANSACTION_SIGN_READY;
-    }
-    context_D.sw = 0x9000;
-    context_D.outLength = 0;
-    G_io_apdu_buffer[context_D.outLength++] = 0x90;
-    G_io_apdu_buffer[context_D.outLength++] = 0x00;
-
-    return 1;
-}
-
-uint8_t prepare_fees(void) {
-    if (context_D.transactionContext.relaxed) {
-        memmove(vars.tmp.feesAmount, "UNKNOWN", 7);
-        vars.tmp.feesAmount[7] = '\0';
-    } else {
-        unsigned char fees[8];
-        unsigned short textSize;
-        unsigned char borrow;
-
-        borrow = transaction_amount_sub_be(
-                fees, context_D.transactionContext.transactionAmount,
-                context_D.totalOutputAmount);
-        if (borrow && COIN_KIND == COIN_KIND_KOMODO) {
-            memmove(vars.tmp.feesAmount, "REWARD", 6);
-            vars.tmp.feesAmount[6] = '\0';
-        }
-        else {
-            if (borrow) {
-                PRINTF("Error : Fees not consistent");
-                goto error;
-            }
-            memmove(vars.tmp.feesAmount, COIN_COINID_SHORT,
-                       strlen(COIN_COINID_SHORT));
-            vars.tmp.feesAmount[strlen(COIN_COINID_SHORT)] = ' ';
-            context_D.tmp =
-                (unsigned char *)(vars.tmp.feesAmount +
-                              strlen(COIN_COINID_SHORT) + 1);
-            textSize = convert_hex_amount_to_displayable(fees);
-            vars.tmp.feesAmount[textSize + strlen(COIN_COINID_SHORT) + 1] =
-                '\0';
-        }
-    }
-    return 1;
-error:
-    return 0;
-}
-
-#define OMNI_ASSETID 1
-#define MAIDSAFE_ASSETID 3
-#define USDT_ASSETID 31
-
-void get_address_from_output_script(unsigned char* script, int script_size, char* out, int out_size) {
-    if (output_script_is_op_return(script)) {
-        strncpy(out, "OP_RETURN", out_size);
-        return;
-    }
-    if ((COIN_KIND == COIN_KIND_HYDRA) &&
-        output_script_is_op_create(script, script_size)) {
-        strncpy(out, "OP_CREATE", out_size);
-        return;
-    }
-    if ((COIN_KIND == COIN_KIND_HYDRA) &&
-        output_script_is_op_call(script, script_size)) {
-        strncpy(out, "OP_CALL", out_size);
-        return;
-    }
-    if (output_script_is_native_witness(script)) {
-        if (COIN_NATIVE_SEGWIT_PREFIX) {
-            segwit_addr_encode(
-                out, (char *)PIC(COIN_NATIVE_SEGWIT_PREFIX), 0,
-                script + OUTPUT_SCRIPT_NATIVE_WITNESS_PROGRAM_OFFSET,
-                script[OUTPUT_SCRIPT_NATIVE_WITNESS_PROGRAM_OFFSET - 1]);
-        }
-        return;
-    }
-    unsigned char versionSize;
-    unsigned char address[22];
-    unsigned short textSize;
-    int addressOffset = 3;
-    unsigned short version = COIN_P2SH_VERSION;
-
-    if (output_script_is_regular(script)) {
-        addressOffset = 4;
-        version = COIN_P2PKH_VERSION;
-    }
-
-    if (version > 255) {
-        versionSize = 2;
-        address[0] = (version >> 8);
-        address[1] = version;
-    } else {
-        versionSize = 1;
-        address[0] = version;
-    }
-    memmove(address + versionSize, script + addressOffset, 20);
-
-    // Prepare address
-    if (context_D.usingCashAddr) {
-        cashaddr_encode(
-            address + versionSize, 20, (uint8_t *)out, out_size,
-            (version == COIN_P2SH_VERSION
-                    ? CASHADDR_P2SH
-                    : CASHADDR_P2PKH));
-    } else {
-        textSize = public_key_to_encoded_base58(
-            address, 20 + versionSize, (unsigned char *)out,
-            out_size, version, 1);
-        out[textSize] = '\0';
-    }
-}
-
-uint8_t prepare_single_output(void) {
-    // TODO : special display for OP_RETURN
-    unsigned char amount[8];
-    unsigned int offset = 0;
-    unsigned short textSize;
-    char tmp[80] = {0};
-
-    swap_bytes(amount, context_D.currentOutput + offset, 8);
-    offset += 8;
-
-    get_address_from_output_script(context_D.currentOutput + offset,  sizeof(context_D.currentOutput) - offset, tmp, sizeof(tmp));
-    strncpy(vars.tmp.fullAddress, tmp, sizeof(vars.tmp.fullAddress) - 1);
-
-    // Prepare amount
-
-    // Handle Omni simple send
-    if ((context_D.currentOutput[offset + 2] == 0x14) &&
-        (memcmp(context_D.currentOutput + offset + 3, "omni", 4) == 0) &&
-        (memcmp(context_D.currentOutput + offset + 3 + 4, "\0\0\0\0", 4) == 0)) {
-            uint8_t headerLength;
-            uint32_t omniAssetId = read_u32_be(context_D.currentOutput, offset + 3 + 4 + 4);
-            switch(omniAssetId) {
-                case OMNI_ASSETID:
-                    strcpy(vars.tmp.fullAmount, "OMNI ");
-                    break;
-                case USDT_ASSETID:
-                    strcpy(vars.tmp.fullAmount, "USDT ");
-                    break;
-                case MAIDSAFE_ASSETID:
-                    strcpy(vars.tmp.fullAmount, "MAID ");
-                    break;
-                default:
-                    snprintf(vars.tmp.fullAmount, sizeof(vars.tmp.fullAmount), "OMNI asset %d ", omniAssetId);
-                    break;
-            }
-            headerLength = strlen(vars.tmp.fullAmount);
-            context_D.tmp = (uint8_t *)vars.tmp.fullAmount + headerLength;
-            textSize = convert_hex_amount_to_displayable(context_D.currentOutput + offset + 3 + 4 + 4 + 4);
-            vars.tmp.fullAmount[textSize + headerLength] = '\0';
-    }
-    else {
-        memmove(vars.tmp.fullAmount, COIN_COINID_SHORT,
-               strlen(COIN_COINID_SHORT));
-        vars.tmp.fullAmount[strlen(COIN_COINID_SHORT)] = ' ';
-        context_D.tmp =
-            (unsigned char *)(vars.tmp.fullAmount +
-                          strlen(COIN_COINID_SHORT) + 1);
-        textSize = convert_hex_amount_to_displayable(amount);
-        vars.tmp.fullAmount[textSize + strlen(COIN_COINID_SHORT) + 1] =
-            '\0';
-    }
-
-    return 1;
-}
-
-uint8_t prepare_message_signature(void) {
-    uint8_t buffer[32];
-
-    if (cx_hash_no_throw(&context_D.transactionHashAuthorization.header, CX_LAST,
-            (uint8_t*)vars.tmp.fullAmount, 0, buffer, 32)) {
-        return 0;
-    }
-
-    format_hex((const uint8_t*) buffer, sizeof(buffer), vars.tmp.fullAddress, sizeof(vars.tmp.fullAddress));
-
-    return 1;
-}
-
-
-extern bool handle_output_state(void);
-extern void apdu_hash_input_finalize_full_reset(void);
-
-// Analog of bagl_confirm_single_output to work
-// in silent mode, when called from SWAP app
-unsigned int silent_confirm_single_output() {
-    char tmp[80] = {0};
-    unsigned char amount[8];
-    while (true) {
-        // in swap operation we can only have 1 "external" output
-        if (vars.swap_data.was_address_checked) {
-            PRINTF("Address was already checked\n");
-            return 0;
-        }
-        vars.swap_data.was_address_checked = 1;
-        // check amount
-        swap_bytes(amount, context_D.currentOutput, 8);
-        if (memcmp(amount, vars.swap_data.amount, 8) != 0) {
-            PRINTF("Amount not matched\n");
-            return 0;
-        }
-        get_address_from_output_script(context_D.currentOutput + 8, sizeof(context_D.currentOutput) - 8, tmp, sizeof(tmp));
-        if (strcmp(tmp, vars.swap_data.destination_address) != 0) {
-            PRINTF("Address not matched\n");
-            return 0;
-        }
-
-        // Check if all inputs have been confirmed
-
-        if (context_D.outputParsingState ==
-            OUTPUT_PARSING_OUTPUT) {
-            context_D.remainingOutputs--;
-            if (context_D.remainingOutputs == 0)
-                break;
-        }
-
-        memmove(context_D.currentOutput,
-                    context_D.currentOutput +
-                        context_D.discardSize,
-                    context_D.currentOutputOffset -
-                        context_D.discardSize);
-        context_D.currentOutputOffset -= context_D.discardSize;
-        context_D.io_flags &= ~IO_ASYNCH_REPLY;
-        while (handle_output_state() &&
-                (!(context_D.io_flags & IO_ASYNCH_REPLY)))
-            ;
-        if (!(context_D.io_flags & IO_ASYNCH_REPLY)) {
-            // Out of data to process, wait for the next call
-            break;
-        }
-    }
-
-    if ((context_D.outputParsingState == OUTPUT_PARSING_OUTPUT) &&
-        (context_D.remainingOutputs == 0)) {
-        context_D.outputParsingState = OUTPUT_FINALIZE_TX;
-        // check fees
-        unsigned char fees[8];
-
-        if ((transaction_amount_sub_be(fees,
-                                       context_D.transactionContext.transactionAmount,
-                                       context_D.totalOutputAmount) != 0) ||
-            (memcmp(fees, vars.swap_data.fees, 8) != 0)) {
-            PRINTF("Fees is not matched\n");
-            return 0;
-        }
-    }
-
-    if (context_D.outputParsingState == OUTPUT_FINALIZE_TX) {
-        context_D.transactionContext.firstSigned = 0;
-
-        if (context_D.usingSegwit &&
-            !context_D.segwitParsedOnce) {
-            // This input cannot be signed when using segwit - just restart.
-            context_D.segwitParsedOnce = 1;
-            PRINTF("Segwit parsed once\n");
-            context_D.transactionContext.transactionState =
-                TRANSACTION_NONE;
-        } else {
-            context_D.transactionContext.transactionState =
-                TRANSACTION_SIGN_READY;
-        }
-    }
-    if (context_D.outputParsingState == OUTPUT_FINALIZE_TX) {
-        // we've finished the processing of the input
-        apdu_hash_input_finalize_full_reset();
-    }
-
-    return 1;
-}
-
-unsigned int bagl_confirm_single_output(void) {
-    if (G_called_from_swap) {
-        return silent_confirm_single_output();
-    }
-    if (!prepare_single_output()) {
-        return 0;
-    }
-
-    ui_confirm_single_flow();
-    return 1;
-}
-
-unsigned int bagl_finalize_tx(void) {
-    if (G_called_from_swap) {
-        return check_fee_swap();
-    }
-
-    if (!prepare_fees()) {
-        return 0;
-    }
-
-    ui_finalize_flow();
-    return 1;
-}
-
-void bagl_confirm_message_signature(void) {
-    if (!prepare_message_signature()) {
-        return;
-    }
-
-    ui_sign_message_flow();
-}
-
-uint8_t set_key_path_to_display(unsigned char* keyPath) {
-    bip32_print_path(keyPath, vars.tmp_warning.derivation_path, MAX_DERIV_PATH_ASCII_LENGTH);
-    return bip44_derivation_guard(keyPath, false);
-}
-
-void bagl_display_public_key(uint8_t is_derivation_path_unusual) {
-    // append a white space at the end of the address to avoid glitch on nano S
-    strlcat((char *)G_io_apdu_buffer + 200, " ", sizeof(G_io_apdu_buffer) - 200);
-
-    if (is_derivation_path_unusual) {
-        ui_display_public_with_warning_flow();
-    }
-    else {
-        ui_display_public_flow();
-    }
-}
-
-void bagl_display_token(void)
-{
-    ui_display_token_flow();
-}
-
-void bagl_request_pubkey_approval(void)
-{
-    ui_request_pubkey_approval_flow();
-}
-
-void bagl_request_change_path_approval(unsigned char* change_path)
-{
-
-    bip32_print_path(change_path, vars.tmp_warning.derivation_path, sizeof(vars.tmp_warning.derivation_path));
-    ui_request_change_path_approval_flow();
-}
-
-void bagl_request_sign_path_approval(unsigned char* change_path)
-{
-    bip32_print_path(change_path, vars.tmp_warning.derivation_path, sizeof(vars.tmp_warning.derivation_path));
-    ui_request_sign_path_approval_flow();
-}
-
-void bagl_request_segwit_input_approval(void)
-{
-    ui_request_segwit_input_approval_flow();
-}
-
-
-#include "os.h"
-
-#include "internal.h"
-
-#include "os_io_seproxyhal.h"
-
-#include "apdu_constants.h"
-#include "display_variables.h"
-
-#include "handle_swap_sign_transaction.h"
-
-#define TECHNICAL_NOT_IMPLEMENTED 0x99
-
-#define COMMON_CLA               0xB0
-
-void app_dispatch(void) {
-    unsigned char cla;
-    unsigned char ins;
-    unsigned char dispatched;
-
-    // nothing to reply for now
-    context_D.outLength = 0;
-    context_D.io_flags = 0;
-
-    cla = G_io_apdu_buffer[ISO_OFFSET_CLA];
-    ins = G_io_apdu_buffer[ISO_OFFSET_INS];
-    for (dispatched = 0; dispatched < DISPATCHER_APDUS; dispatched++) {
-        if ((cla == DISPATCHER_CLA[dispatched]) &&
-                (ins == DISPATCHER_INS[dispatched])) {
-            break;
-        }
-    }
-    if (dispatched == DISPATCHER_APDUS) {
-        context_D.sw = SW_INS_NOT_SUPPORTED;
-        goto sendSW;
-    }
-    if (DISPATCHER_DATA_IN[dispatched]) {
-        if (G_io_apdu_buffer[ISO_OFFSET_LC] == 0x00 ||
-                context_D.inLength - 5 == 0) {
-            context_D.sw = SW_INCORRECT_LENGTH;
-            goto sendSW;
-        }
-        // notify we need to receive data
-        // io_exchange(CHANNEL_APDU | IO_RECEIVE_DATA, 0);
-    }
-    // call the apdu handler
-    context_D.sw = ((apduProcessingFunction)PIC(
-                DISPATCHER_FUNCTIONS[dispatched]))();
-
-    // an APDU has been replied. request for power off time extension from the
-    // common ux
-#ifdef IO_APP_ACTIVITY
-    IO_APP_ACTIVITY();
-#endif // IO_APP_ACTIVITY
-
-sendSW:
-    if (G_called_from_swap) {
-        context_D.io_flags &= ~IO_ASYNCH_REPLY;
-        if(context_D.sw != SW_OK) {
-            vars.swap_data.should_exit = 1;
-        }
-    }
-    // prepare SW after replied data
-    G_io_apdu_buffer[context_D.outLength] =
-        (context_D.sw >> 8);
-    G_io_apdu_buffer[context_D.outLength + 1] =
-        (context_D.sw & 0xff);
-    context_D.outLength += 2;
-    return;
-}
-
-void app_main(void) {
-    context_init();
-
-    ui_idle_flow();
-
-    memset(G_io_apdu_buffer, 0, 255); // paranoia
-
-    // Process the incoming APDUs
-
-    // first exchange, no out length :) only wait the apdu
-    context_D.outLength = 0;
-    context_D.io_flags = 0;
-    for (;;) {
-
-        // memset(G_io_apdu_buffer, 0, 255); // paranoia
-
-        if (G_called_from_swap && vars.swap_data.should_exit) {
-            context_D.io_flags |= IO_RETURN_AFTER_TX;
-        }
-
-        // receive the whole apdu using the 7 bytes headers (ledger transport)
-        context_D.inLength =
-            io_exchange(CHANNEL_APDU | context_D.io_flags,
-                        // use the previous outlength as the reply
-                        context_D.outLength);
-
-        if (G_called_from_swap && vars.swap_data.should_exit) {
-            swap_finalize_exchange_sign_transaction(context_D.sw == SW_OK);
-        }
-
-        PRINTF("New APDU received:\n%.*H\n", context_D.inLength, G_io_apdu_buffer);
-
-        app_dispatch();
-
-        // reply during reception of next apdu
-    }
-
-    PRINTF("End of main loop\n");
-
-    // in case reached
-    reset();
-}
diff --git a/src/ecc.c b/src/ecc.c
deleted file mode 100644
index 69092c81..00000000
--- a/src/ecc.c
+++ /dev/null
@@ -1,22 +0,0 @@
-/*******************************************************************************
-*   Ledger App - Bitcoin Wallet
-*   (c) 2016-2019 Ledger
-*
-*  Licensed under the Apache License, Version 2.0 (the "License");
-*  you may not use this file except in compliance with the License.
-*  You may obtain a copy of the License at
-*
-*      http://www.apache.org/licenses/LICENSE-2.0
-*
-*  Unless required by applicable law or agreed to in writing, software
-*  distributed under the License is distributed on an "AS IS" BASIS,
-*  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-*  See the License for the specific language governing permissions and
-*  limitations under the License.
-********************************************************************************/
-
-#include "internal.h"
-
-void compress_public_key_value(unsigned char *value) {
-    value[0] = ((value[64] & 1) ? 0x03 : 0x02);
-}
diff --git a/src/helpers.c b/src/helpers.c
deleted file mode 100644
index 605acb06..00000000
--- a/src/helpers.c
+++ /dev/null
@@ -1,407 +0,0 @@
-/*******************************************************************************
-*   Ledger App - Bitcoin Wallet
-*   (c) 2016-2019 Ledger
-*
-*  Licensed under the Apache License, Version 2.0 (the "License");
-*  you may not use this file except in compliance with the License.
-*  You may obtain a copy of the License at
-*
-*      http://www.apache.org/licenses/LICENSE-2.0
-*
-*  Unless required by applicable law or agreed to in writing, software
-*  distributed under the License is distributed on an "AS IS" BASIS,
-*  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-*  See the License for the specific language governing permissions and
-*  limitations under the License.
-********************************************************************************/
-
-#include "internal.h"
-#include "apdu_constants.h"
-#include "lib_standard_app/crypto_helpers.h"
-#include "lib_standard_app/read.h"
-#include "lib_standard_app/base58.h"
-#include "bip32_path.h"
-#include "ledger_assert.h"
-
-const unsigned char TRANSACTION_OUTPUT_SCRIPT_PRE[] = {
-    0x19, 0x76, 0xA9,
-    0x14}; // script length, OP_DUP, OP_HASH160, address length
-const unsigned char TRANSACTION_OUTPUT_SCRIPT_POST[] = {
-    0x88, 0xAC}; // OP_EQUALVERIFY, OP_CHECKSIG
-
-const unsigned char TRANSACTION_OUTPUT_SCRIPT_P2SH_PRE[] = {
-    0x17, 0xA9, 0x14}; // script length, OP_HASH160, address length
-const unsigned char TRANSACTION_OUTPUT_SCRIPT_P2SH_POST[] = {0x87}; // OP_EQUAL
-
-const unsigned char ZEN_TRANSACTION_OUTPUT_SCRIPT_P2SH_PRE[] = {
-        0x3D, 0xA9,
-        0x14}; // script length, OP_HASH160, address length
-
-const unsigned char ZEN_TRANSACTION_OUTPUT_SCRIPT_P2SH_POST[] = {
-        0x87, // OP_EQUAL
-        0x20, 0x9E, 0xC9, 0x84, 0x5A, 0xCB, 0x02, 0xFA, 0XB2, 0X4E,
-        0x1C, 0x03, 0x68, 0xB3, 0xB5, 0x17, 0xC1, 0xA4, 0x48, 0x8F,
-        0xBA, 0x97, 0xF0, 0xE3, 0x45, 0x9A, 0xC0, 0x53, 0xEA, 0x01,
-        0x00, 0x00, 0x00, // ParamHash
-        0x03, // Push 3 bytes to stack to make ParamHeight line up properly
-        0xC0, 0x1F, 0x02, // ParamHeight (139200) -> hex -> endianness swapped
-        0xB4};            // OP_CHECKBLOCKATHEIGHT
-
-const unsigned char TRANSACTION_OUTPUT_SCRIPT_P2WPKH_PRE[] = {0x16, 0x00, 0x14};
-const unsigned char TRANSACTION_OUTPUT_SCRIPT_P2WSH_PRE[] = {0x22, 0x00, 0x20};
-
-const unsigned char ZEN_OUTPUT_SCRIPT_PRE[] = {
-    0x3F, 0x76, 0xA9,
-    0x14}; // script length, OP_DUP, OP_HASH160, address length
-const unsigned char ZEN_OUTPUT_SCRIPT_POST[] = {
-    0x88, 0xAC, // OP_EQUALVERIFY, OP_CHECKSIG
-    0x20, 0x9e, 0xc9, 0x84, 0x5a, 0xcb, 0x02, 0xfa, 0xb2, 0x4e, 0x1c, 0x03,
-    0x68, 0xb3, 0xb5, 0x17, 0xc1, 0xa4, 0x48, 0x8f, 0xba, 0x97, 0xf0, 0xe3,
-    0x45, 0x9a, 0xc0, 0x53, 0xea, 0x01, 0x00, 0x00, 0x00, // ParamHash
-    0x03, // Push 3 bytes to stack to make ParamHeight line up properly
-    0xc0, 0x1f, 0x02, // ParamHeight (139200) -> hex -> endianness swapped
-    0xb4              // OP_CHECKBLOCKATHEIGHT
-};                    // BIP0115 Replay Protection
-
-unsigned char output_script_is_regular(unsigned char *buffer) {
-    if (COIN_NATIVE_SEGWIT_PREFIX) {
-        if ((memcmp(buffer, TRANSACTION_OUTPUT_SCRIPT_P2WPKH_PRE,
-                       sizeof(TRANSACTION_OUTPUT_SCRIPT_P2WPKH_PRE)) == 0) ||
-            (memcmp(buffer, TRANSACTION_OUTPUT_SCRIPT_P2WSH_PRE,
-                       sizeof(TRANSACTION_OUTPUT_SCRIPT_P2WSH_PRE)) == 0)) {
-            return 1;
-        }
-    }
-    if ((memcmp(buffer, TRANSACTION_OUTPUT_SCRIPT_PRE,
-                       sizeof(TRANSACTION_OUTPUT_SCRIPT_PRE)) == 0) &&
-        (memcmp(buffer + sizeof(TRANSACTION_OUTPUT_SCRIPT_PRE) + 20,
-                       TRANSACTION_OUTPUT_SCRIPT_POST,
-                       sizeof(TRANSACTION_OUTPUT_SCRIPT_POST)) == 0)) {
-        return 1;
-    }
-    if (COIN_KIND == COIN_KIND_HORIZEN) {
-        if ((memcmp(buffer, ZEN_OUTPUT_SCRIPT_PRE,
-                       sizeof(ZEN_OUTPUT_SCRIPT_PRE)) == 0) &&
-            (memcmp(buffer + sizeof(ZEN_OUTPUT_SCRIPT_PRE) + 20,
-                       ZEN_OUTPUT_SCRIPT_POST,
-                       sizeof(ZEN_OUTPUT_SCRIPT_POST)) == 0)) {
-            return 1;
-        }
-    }
-
-    return 0;
-}
-
-unsigned char output_script_is_p2sh(unsigned char *buffer) {
-    if ((memcmp(buffer, TRANSACTION_OUTPUT_SCRIPT_P2SH_PRE,
-                    sizeof(TRANSACTION_OUTPUT_SCRIPT_P2SH_PRE)) == 0) &&
-        (memcmp(buffer + sizeof(TRANSACTION_OUTPUT_SCRIPT_P2SH_PRE) + 20,
-                    TRANSACTION_OUTPUT_SCRIPT_P2SH_POST,
-                    sizeof(TRANSACTION_OUTPUT_SCRIPT_P2SH_POST)) == 0)) {
-        return 1;
-    }
-    if (COIN_KIND == COIN_KIND_HORIZEN) {
-        if ((memcmp(buffer, ZEN_TRANSACTION_OUTPUT_SCRIPT_P2SH_PRE,
-                       sizeof(ZEN_TRANSACTION_OUTPUT_SCRIPT_P2SH_PRE)) == 0) &&
-            (memcmp(buffer + sizeof(ZEN_TRANSACTION_OUTPUT_SCRIPT_P2SH_PRE) + 20,
-                       ZEN_TRANSACTION_OUTPUT_SCRIPT_P2SH_POST,
-                       sizeof(ZEN_TRANSACTION_OUTPUT_SCRIPT_P2SH_POST)) == 0)) {
-            return 1;
-        }
-    }
-    return 0;
-}
-
-unsigned char output_script_is_native_witness(unsigned char *buffer) {
-    if (COIN_NATIVE_SEGWIT_PREFIX) {
-        if ((memcmp(buffer, TRANSACTION_OUTPUT_SCRIPT_P2WPKH_PRE,
-                       sizeof(TRANSACTION_OUTPUT_SCRIPT_P2WPKH_PRE)) == 0) ||
-            (memcmp(buffer, TRANSACTION_OUTPUT_SCRIPT_P2WSH_PRE,
-                       sizeof(TRANSACTION_OUTPUT_SCRIPT_P2WSH_PRE)) == 0)) {
-            return 1;
-        }
-    }
-    return 0;
-}
-
-unsigned char output_script_is_op_return(unsigned char *buffer) {
-    if (COIN_KIND == COIN_KIND_BITCOIN_CASH) {
-        return ((buffer[1] == 0x6A) || ((buffer[1] == 0x00) && (buffer[2] == 0x6A)));
-    }
-    else {
-        return (buffer[1] == 0x6A);
-    }
-}
-
-static unsigned char output_script_is_op_create_or_call(unsigned char *buffer,
-                                                        size_t size,
-                                                        unsigned char value) {
-    return (!output_script_is_regular(buffer) &&
-            !output_script_is_p2sh(buffer) &&
-            !output_script_is_op_return(buffer) && (buffer[0] <= 0xEA) &&
-            (buffer[0] < size) &&
-            (buffer[buffer[0]] == value));
-}
-
-unsigned char output_script_is_op_create(unsigned char *buffer,
-                                                size_t size) {
-    return output_script_is_op_create_or_call(buffer, size, 0xC1);
-}
-
-unsigned char output_script_is_op_call(unsigned char *buffer,
-                                              size_t size) {
-    return output_script_is_op_create_or_call(buffer, size, 0xC2);
-}
-
-void public_key_hash160(unsigned char *in, unsigned short inlen,
-                               unsigned char *out) {
-    cx_ripemd160_t riprip;
-    unsigned char buffer[32];
-    cx_hash_sha256(in, inlen, buffer, 32);
-    cx_ripemd160_init(&riprip);
-    LEDGER_ASSERT(cx_hash_no_throw(&riprip.header, CX_LAST, buffer, 32, out, 20) == CX_OK, "hash160");
-}
-
-void compute_checksum(unsigned char* in, unsigned short inlen, unsigned char * output) {
-    unsigned char checksumBuffer[32];
-    cx_hash_sha256(in, inlen, checksumBuffer, 32);
-    cx_hash_sha256(checksumBuffer, 32, checksumBuffer, 32);
-
-    PRINTF("Checksum\n%.*H\n",4,checksumBuffer);
-    memmove(output, checksumBuffer, 4);
-}
-
-unsigned short public_key_to_encoded_base58(
-    unsigned char *in, unsigned short inlen, unsigned char *out,
-    unsigned short outlen, unsigned short version,
-    unsigned char alreadyHashed) {
-    unsigned char tmpBuffer[34];
-
-    unsigned char versionSize = (version > 255 ? 2 : 1);
-    size_t outputLen;
-
-    if (!alreadyHashed) {
-        PRINTF("To hash\n%.*H\n",inlen,in);
-        public_key_hash160(in, inlen, tmpBuffer + versionSize);
-        PRINTF("Hash160\n%.*H\n",20,(tmpBuffer + versionSize));
-        if (version > 255) {
-            tmpBuffer[0] = (version >> 8);
-            tmpBuffer[1] = version;
-        } else {
-            tmpBuffer[0] = version;
-        }
-    } else {
-        memmove(tmpBuffer, in, 20 + versionSize);
-    }
-
-    compute_checksum(tmpBuffer, 20 + versionSize, tmpBuffer + 20 + versionSize);
-
-    outputLen = base58_encode(tmpBuffer, 24 + versionSize, (char *)out, outlen);
-    if (outputLen < 0) {
-        THROW(EXCEPTION);
-    }
-    return outputLen;
-}
-
-void swap_bytes(unsigned char *target, unsigned char *source,
-                       unsigned char size) {
-    unsigned char i;
-    for (i = 0; i < size; i++) {
-        target[i] = source[size - 1 - i];
-    }
-}
-
-/*
-Checks if the values of a derivation path are within "normal" (arbitrary) ranges:
-Account < 100, change == 1 or 0, address index < 50000
-Returns 1 if the path is unusual, or not compliant with BIP44*/
-unsigned char bip44_derivation_guard(unsigned char *bip32Path, bool is_change_path) {
-
-    unsigned char path_len;
-    bip32_path_t bip32PathInt;
-
-    path_len = bip32Path[0];
-    if (!parse_serialized_path(&bip32PathInt, bip32Path, MAX_BIP32_PATH_LENGTH)) {
-        return 1;
-    }
-
-    // If the path length is not compliant with BIP44 or if the purpose don't match regular usage, return a warning
-    if(path_len != BIP44_PATH_LEN ||
-       ((bip32PathInt.path[BIP44_PURPOSE_OFFSET]^0x80000000) != 44 &&
-       (bip32PathInt.path[BIP44_PURPOSE_OFFSET]^0x80000000) != 49 &&
-       (bip32PathInt.path[BIP44_PURPOSE_OFFSET]^0x80000000) != 84)) {
-        return 1;
-    }
-
-    // If the coin type doesn't match, return a warning
-    if ((BIP44_COIN_TYPE != 0) &&
-        (((bip32PathInt.path[BIP44_COIN_TYPE_OFFSET]^0x80000000) != BIP44_COIN_TYPE) &&
-          ((bip32PathInt.path[BIP44_COIN_TYPE_OFFSET]^0x80000000) != BIP44_COIN_TYPE_2))) {
-        return 1;
-    }
-
-    // If the account or address index is very high or if the change isn't 1, return a warning
-    if((bip32PathInt.path[BIP44_ACCOUNT_OFFSET]^0x80000000) > MAX_BIP44_ACCOUNT_RECOMMENDED ||
-       bip32PathInt.path[BIP44_CHANGE_OFFSET] != is_change_path?1:0 ||
-       bip32PathInt.path[BIP44_ADDRESS_INDEX_OFFSET] > MAX_BIP44_ADDRESS_INDEX_RECOMMENDED) {
-        return 1;
-    }
-
-    return 0;
-}
-
-/*
-Only enforce the structure or coin type for consumed UTXOs or a public address
-Returns 0 if the path is non compliant, or 1 if compliant
-*/
-unsigned char enforce_bip44_coin_type(unsigned char *bip32Path, bool for_pubkey) {
-    bip32_path_t bip32PathInt;
-    // No enforcement required
-    if (BIP44_COIN_TYPE == 0) {
-        return 1;
-    }
-    // Path is too short - always require a user validation if signing
-    if (bip32Path[0] < 2) {
-        return for_pubkey;
-    }
-
-    if (!parse_serialized_path(&bip32PathInt, bip32Path, MAX_BIP32_PATH_LENGTH)) {
-        return 1;
-    }
-
-    // Path is not compliant with BIP 44 or derivatives - valid if not signing
-    if (!(((bip32PathInt.path[BIP44_PURPOSE_OFFSET]^0x80000000) == 44 ||
-       (bip32PathInt.path[BIP44_PURPOSE_OFFSET]^0x80000000) == 49 ||
-       (bip32PathInt.path[BIP44_PURPOSE_OFFSET]^0x80000000) == 84))) {
-        return for_pubkey;
-    }
-
-    if  (((bip32PathInt.path[BIP44_COIN_TYPE_OFFSET]^0x80000000) == BIP44_COIN_TYPE) ||
-        ((bip32PathInt.path[BIP44_COIN_TYPE_OFFSET]^0x80000000) == BIP44_COIN_TYPE_2)) {
-        // Valid BIP 44 path
-        return 1;
-    }
-    // Everything else needs a user validation
-    return 0;
-}
-
-// Print a BIP32 path as an ascii string to display on the device screen
-// On the Ledger Blue, if the string is longer than 30 char, the string will be split in multiple lines
-unsigned char bip32_print_path(unsigned char *bip32Path, char* out, unsigned char max_out_len) {
-
-    unsigned char bip32PathLength;
-    unsigned char i, offset;
-    unsigned int current_level;
-    bool hardened;
-
-    bip32PathLength = bip32Path[0];
-    if (bip32PathLength > MAX_BIP32_PATH) {
-        THROW(INVALID_PARAMETER);
-    }
-    bip32Path++;
-    out[0] = ' ';
-    offset=1;
-    for (i = 0; i < bip32PathLength; i++) {
-        current_level = read_u32_be(bip32Path, 0);
-        hardened = (bool)(current_level & 0x80000000);
-        if(hardened) {
-            //remove hardening flag
-            current_level ^= 0x80000000;
-        }
-        bip32Path += 4;
-        snprintf(out+offset, max_out_len-offset, "%u", current_level);
-        offset = strnlen(out, max_out_len);
-        if(offset >= max_out_len - 2) THROW(EXCEPTION_OVERFLOW);
-        if(hardened) out[offset++] = '\'';
-
-        out[offset++] = '/';
-        out[offset] = '\0';
-    }
-    // remove last '/'
-    out[offset-1] = '\0';
-
-    return offset -1;
-}
-
-void transaction_add_output(unsigned char *hash160Address,
-                                   unsigned char *amount, unsigned char p2sh) {
-    const unsigned char *pre = (p2sh ? TRANSACTION_OUTPUT_SCRIPT_P2SH_PRE
-                                     : TRANSACTION_OUTPUT_SCRIPT_PRE);
-    const unsigned char *post = (p2sh ? TRANSACTION_OUTPUT_SCRIPT_P2SH_POST
-                                      : TRANSACTION_OUTPUT_SCRIPT_POST);
-    unsigned char sizePre = (p2sh ? sizeof(TRANSACTION_OUTPUT_SCRIPT_P2SH_PRE)
-                                  : sizeof(TRANSACTION_OUTPUT_SCRIPT_PRE));
-    unsigned char sizePost = (p2sh ? sizeof(TRANSACTION_OUTPUT_SCRIPT_P2SH_POST)
-                                   : sizeof(TRANSACTION_OUTPUT_SCRIPT_POST));
-    if (amount != NULL) {
-        swap_bytes(context_D.tmp, amount, 8);
-        context_D.tmp += 8;
-    }
-    memmove(context_D.tmp, (void *)pre, sizePre);
-    context_D.tmp += sizePre;
-    memmove(context_D.tmp, hash160Address, 20);
-    context_D.tmp += 20;
-    memmove(context_D.tmp, (void *)post, sizePost);
-    context_D.tmp += sizePost;
-}
-
-
-int sign_finalhash(unsigned char* path, size_t path_len, unsigned char *in, unsigned short inlen,
-                                 unsigned char *out, size_t* outlen,
-                                 unsigned char rfc6979) {
-
-    unsigned int info = 0;
-
-    io_seproxyhal_io_heartbeat();
-    
-    bip32_path_t bip32Path;
-    bip32Path.length = path[0];
-
-    if (!parse_serialized_path(&bip32Path, path, path_len)) {
-        return -1;
-    }
-
-    if (bip32_derive_ecdsa_sign_hash_256(
-            CX_CURVE_SECP256K1,
-            bip32Path.path, 
-            bip32Path.length,
-            CX_LAST | (rfc6979 ? CX_RND_RFC6979 : CX_RND_TRNG), 
-            CX_SHA256,
-            in, 
-            inlen, 
-            out, 
-            outlen,
-            &info) != CX_OK) {
-        return -1;
-    }
-
-    // Store information about the parity of the 'y' coordinate
-    if (info & CX_ECCINFO_PARITY_ODD) {
-        out[0] |= 0x01;
-    }
-
-    io_seproxyhal_io_heartbeat();
-    return 0;
-}
-
-int get_public_key(unsigned char* keyPath, size_t keyPath_len, uint8_t raw_pubkey[static 65], unsigned char* chainCode) {
-
-    bip32_path_t bip32Path;
-
-    if (!parse_serialized_path(&bip32Path, keyPath, keyPath_len)) {
-        return -1;
-    }
-
-    if (bip32_derive_get_pubkey_256(
-        CX_CURVE_SECP256K1,
-        bip32Path.path, 
-        bip32Path.length,
-        raw_pubkey,
-        chainCode,
-        CX_SHA512) != CX_OK) 
-    {
-        return -1;
-    }
-
-    return 0;
-}
diff --git a/src/internal.h b/src/internal.h
deleted file mode 100644
index 1b84471e..00000000
--- a/src/internal.h
+++ /dev/null
@@ -1,30 +0,0 @@
-/*******************************************************************************
-*   Ledger App - Bitcoin Wallet
-*   (c) 2016-2019 Ledger
-*
-*  Licensed under the Apache License, Version 2.0 (the "License");
-*  you may not use this file except in compliance with the License.
-*  You may obtain a copy of the License at
-*
-*      http://www.apache.org/licenses/LICENSE-2.0
-*
-*  Unless required by applicable law or agreed to in writing, software
-*  distributed under the License is distributed on an "AS IS" BASIS,
-*  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-*  See the License for the specific language governing permissions and
-*  limitations under the License.
-********************************************************************************/
-
-#ifndef INTERNAL_H
-#define INTERNAL_H
-
-#include "btchip.h"
-#include "public_ram_variables.h"
-#include "rom_variables.h"
-#include "filesystem.h"
-#include "bcd.h"
-#include "ecc.h"
-#include "helpers.h"
-#include "transaction.h"
-
-#endif
diff --git a/src/nvram.c b/src/nvram.c
deleted file mode 100644
index a956708f..00000000
--- a/src/nvram.c
+++ /dev/null
@@ -1,22 +0,0 @@
-/*******************************************************************************
-*   Ledger App - Bitcoin Wallet
-*   (c) 2016-2019 Ledger
-*
-*  Licensed under the Apache License, Version 2.0 (the "License");
-*  you may not use this file except in compliance with the License.
-*  You may obtain a copy of the License at
-*
-*      http://www.apache.org/licenses/LICENSE-2.0
-*
-*  Unless required by applicable law or agreed to in writing, software
-*  distributed under the License is distributed on an "AS IS" BASIS,
-*  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-*  See the License for the specific language governing permissions and
-*  limitations under the License.
-********************************************************************************/
-
-#include "internal.h"
-
-#include "public_ram_variables.h"
-
-storage_t const N_real;
diff --git a/src/public_ram_variables.c b/src/public_ram_variables.c
deleted file mode 100644
index a0acc359..00000000
--- a/src/public_ram_variables.c
+++ /dev/null
@@ -1,21 +0,0 @@
-/*******************************************************************************
-*   Ledger App - Bitcoin Wallet
-*   (c) 2016-2019 Ledger
-*
-*  Licensed under the Apache License, Version 2.0 (the "License");
-*  you may not use this file except in compliance with the License.
-*  You may obtain a copy of the License at
-*
-*      http://www.apache.org/licenses/LICENSE-2.0
-*
-*  Unless required by applicable law or agreed to in writing, software
-*  distributed under the License is distributed on an "AS IS" BASIS,
-*  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-*  See the License for the specific language governing permissions and
-*  limitations under the License.
-********************************************************************************/
-
-#include "public_ram_variables.h"
-
-context_t context_D;
-
diff --git a/src/rom_variables.c b/src/rom_variables.c
deleted file mode 100644
index 375e3d86..00000000
--- a/src/rom_variables.c
+++ /dev/null
@@ -1,72 +0,0 @@
-/*******************************************************************************
-*   Ledger App - Bitcoin Wallet
-*   (c) 2016-2019 Ledger
-*
-*  Licensed under the Apache License, Version 2.0 (the "License");
-*  you may not use this file except in compliance with the License.
-*  You may obtain a copy of the License at
-*
-*      http://www.apache.org/licenses/LICENSE-2.0
-*
-*  Unless required by applicable law or agreed to in writing, software
-*  distributed under the License is distributed on an "AS IS" BASIS,
-*  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-*  See the License for the specific language governing permissions and
-*  limitations under the License.
-********************************************************************************/
-
-#include "internal.h"
-#include "apdu_constants.h"
-
-unsigned char const SIGNMAGIC[] = {' ', 'S', 'i', 'g', 'n', 'e', 'd', ' ', 'M',
-                                   'e', 's', 's', 'a', 'g', 'e', ':', '\n'};
-
-unsigned char const OVERWINTER_PARAM_PREVOUTS[16] = { 'Z', 'c', 'a', 's', 'h', 'P', 'r', 'e', 'v', 'o', 'u', 't', 'H', 'a', 's', 'h' };
-unsigned char const OVERWINTER_PARAM_SEQUENCE[16] = { 'Z', 'c', 'a', 's', 'h', 'S', 'e', 'q', 'u', 'e', 'n', 'c', 'H', 'a', 's', 'h' };
-unsigned char const OVERWINTER_PARAM_OUTPUTS[16] = { 'Z', 'c', 'a', 's', 'h', 'O', 'u', 't', 'p', 'u', 't', 's', 'H', 'a', 's', 'h' };
-unsigned char const OVERWINTER_PARAM_SIGHASH[16] = { 'Z', 'c', 'a', 's', 'h', 'S', 'i', 'g', 'H', 'a', 's', 'h', 0, 0, 0, 0 };
-unsigned char const OVERWINTER_NO_JOINSPLITS[32] = { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 };
-
-unsigned char const DISPATCHER_CLA[] = {
-    CLA, // apdu_get_wallet_public_key,
-    CLA, // apdu_get_trusted_input,
-    CLA, // apdu_hash_input_start,
-    CLA, // apdu_hash_sign,
-    CLA, // apdu_hash_input_finalize_full,
-    CLA, // apdu_sign_message,
-    CLA, // apdu_get_firmware_version,
-    CLA, // apdu_get_coin_version
-};
-
-unsigned char const DISPATCHER_INS[] = {
-    INS_GET_WALLET_PUBLIC_KEY,    // apdu_get_wallet_public_key,
-    INS_GET_TRUSTED_INPUT,        // apdu_get_trusted_input,
-    INS_HASH_INPUT_START,         // apdu_hash_input_start,
-    INS_HASH_SIGN,                // apdu_hash_sign,
-    INS_HASH_INPUT_FINALIZE_FULL, // apdu_hash_input_finalize_full,
-    INS_SIGN_MESSAGE,             // apdu_sign_message,
-    INS_GET_FIRMWARE_VERSION,     // apdu_get_firmware_version,
-    INS_GET_COIN_VER,           // apdu_get_coin_version
-};
-
-unsigned char const DISPATCHER_DATA_IN[] = {
-    1, // apdu_get_wallet_public_key,
-    1, // apdu_get_trusted_input,
-    1, // apdu_hash_input_start,
-    1, // apdu_hash_sign,
-    1, // apdu_hash_input_finalize_full,
-    1, // apdu_sign_message,
-    0, // apdu_get_firmware_version,
-    0, // apdu_get_coin_version
-};
-
-apduProcessingFunction const DISPATCHER_FUNCTIONS[] = {
-    apdu_get_wallet_public_key,
-    apdu_get_trusted_input,
-    apdu_hash_input_start,
-    apdu_hash_sign,
-    apdu_hash_input_finalize_full,
-    apdu_sign_message,
-    apdu_get_firmware_version,
-    apdu_get_coin_version,
-};
diff --git a/src/rom_variables.h b/src/rom_variables.h
deleted file mode 100644
index 82d5fa89..00000000
--- a/src/rom_variables.h
+++ /dev/null
@@ -1,64 +0,0 @@
-/*******************************************************************************
-*   Ledger App - Bitcoin Wallet
-*   (c) 2016-2019 Ledger
-*
-*  Licensed under the Apache License, Version 2.0 (the "License");
-*  you may not use this file except in compliance with the License.
-*  You may obtain a copy of the License at
-*
-*      http://www.apache.org/licenses/LICENSE-2.0
-*
-*  Unless required by applicable law or agreed to in writing, software
-*  distributed under the License is distributed on an "AS IS" BASIS,
-*  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-*  See the License for the specific language governing permissions and
-*  limitations under the License.
-********************************************************************************/
-
-#ifndef _ROM_VARIABLES_
-#define _ROM_VARIABLES_
-
-#include "internal.h"
-
-#define SIGNMAGIC_LENGTH 17
-
-extern unsigned char const SIGNMAGIC[SIGNMAGIC_LENGTH];
-
-extern unsigned char const OVERWINTER_PARAM_PREVOUTS[16];
-extern unsigned char const OVERWINTER_PARAM_SEQUENCE[16];
-extern unsigned char const OVERWINTER_PARAM_OUTPUTS[16];
-extern unsigned char const OVERWINTER_PARAM_SIGHASH[16];
-extern unsigned char const OVERWINTER_NO_JOINSPLITS[32];
-
-#define HDKEY_VERSION_LENGTH 4
-
-#define APDU_DEBUG_LENGTH 0
-
-#define APDU_NFCPAYMENT_LENGTH 0
-
-#define APDU_BIP70_LENGTH 0
-
-#define APDU_MOFN_LENGTH 0
-
-#define APDU_KEYCARD_LENGTH 0
-
-#define APDU_PORTABLE_LENGTH 5
-
-#define APDU_KEYBOARD_LENGTH 0
-
-#define APDU_LEGACY_SETUP_LENGTH 0
-
-#define APDU_DEVELOPER_MODE_LENGTH 0
-
-#define APDU_BASE_LENGTH 13
-
-#define DISPATCHER_APDUS 13
-
-typedef unsigned short (*apduProcessingFunction)(void);
-
-extern unsigned char const DISPATCHER_CLA[DISPATCHER_APDUS];
-extern unsigned char const DISPATCHER_INS[DISPATCHER_APDUS];
-extern unsigned char const DISPATCHER_DATA_IN[DISPATCHER_APDUS];
-extern apduProcessingFunction const DISPATCHER_FUNCTIONS[DISPATCHER_APDUS];
-
-#endif /* _ROM_VARIABLES_ */
\ No newline at end of file
diff --git a/src/swap/handle_get_printable_amount.c b/src/swap/handle_get_printable_amount.c
deleted file mode 100644
index 8f9d8fd7..00000000
--- a/src/swap/handle_get_printable_amount.c
+++ /dev/null
@@ -1,21 +0,0 @@
-#include "handle_get_printable_amount.h"
-#include "bcd.h"
-#include <string.h>
-
-void swap_handle_get_printable_amount(get_printable_amount_parameters_t* params) {
-    params->printable_amount[0] = 0;
-    if (params->amount_length > 8) {
-        PRINTF("Amount is too big");
-        return;
-    }
-    unsigned char amount[8];
-    memset(amount, 0, 8);
-    memcpy(amount + (8 - params->amount_length), params->amount, params->amount_length);
-    unsigned char coin_name_length = strlen(COIN_COINID_SHORT);
-    memmove(params->printable_amount, COIN_COINID_SHORT, coin_name_length);
-    params->printable_amount[coin_name_length] = ' ';
-    int res_length = convert_hex_amount_to_displayable_no_globals(amount, COIN_FLAGS, (uint8_t *)params->printable_amount + coin_name_length + 1);
-    params->printable_amount[res_length + coin_name_length + 1] = '\0';
-
-    return;
-}
\ No newline at end of file