diff --git a/src/CWL/ARCtrl.CWL.fsproj b/src/CWL/ARCtrl.CWL.fsproj
index b709cf8c..6db6da17 100644
--- a/src/CWL/ARCtrl.CWL.fsproj
+++ b/src/CWL/ARCtrl.CWL.fsproj
@@ -8,6 +8,30 @@
   <Import Project="../Package.Metadata.props" />
   
   <ItemGroup> 
+    <Compile Include="CWLTypes.fs" /> 
+    <Compile Include="Requirements.fs" /> 
+    <Compile Include="Inputs.fs" /> 
+    <Compile Include="Outputs.fs" /> 
+    <Compile Include="CWL.fs" /> 
+    <Compile Include="Decode.fs" />
+    <Compile Include="Encode.fs" />
     <Compile Include="Library.fs" />
   </ItemGroup>
+  <ItemGroup>
+    <None Include="../../build/logo.png" Pack="true" PackagePath="\" />
+  </ItemGroup>
+  <ItemGroup>
+    <PackageReference Include="YAMLicious" Version="[0.0.2]" />
+    <PackageReference Include="DynamicObj" Version="[2.0.0]" />
+  </ItemGroup>
+  <PropertyGroup>
+    <Authors>nfdi4plants</Authors>
+    <Description>ARC helper functions for Common workflow language.</Description>
+    <PackageLicenseExpression>MIT</PackageLicenseExpression>
+    <PackageIcon>logo.png</PackageIcon>
+    <PackageTags>ARC F# FSharp dotnet .Net bioinformatics biology fable-library datascience dataplant nfdi metadata</PackageTags>
+    <PackageProjectUrl>https://github.com/nfdi4plants/ARCtrl/tree/main/src/CWL</PackageProjectUrl>
+    <RepositoryUrl>https://github.com/nfdi4plants/ARCtrl</RepositoryUrl>
+    <RepositoryType>git</RepositoryType>
+  </PropertyGroup>
 </Project>
diff --git a/src/CWL/Decode.fs b/src/CWL/Decode.fs
new file mode 100644
index 00000000..5f494a0b
--- /dev/null
+++ b/src/CWL/Decode.fs
@@ -0,0 +1,185 @@
+namespace ARCtrl.CWL
+
+open YAMLicious
+
+module Decode =
+    
+    let outputBindingGlobDecoder: (YAMLiciousTypes.YAMLElement -> OutputBinding) =
+        Decode.object (fun get ->
+            let glob = get.Optional.Field "glob" Decode.string
+            { Glob = glob }
+        )
+
+    let outputBindingDecoder: (YAMLiciousTypes.YAMLElement -> OutputBinding) =
+        Decode.object(fun get ->
+            let outputBinding = get.Required.Field "outputBinding" outputBindingGlobDecoder
+            outputBinding
+        )
+
+    let cwlArrayTypeDecoder: (YAMLiciousTypes.YAMLElement -> CWLType) =
+        Decode.object (fun get ->
+            let items = get.Required.Field "items" Decode.string
+            match items with
+            | "File" -> Array (File (FileInstance ()))
+            | "Directory" -> Array (Directory (DirectoryInstance ()))
+            | "Dirent" -> Array (Dirent { Entry = ""; Entryname = None; Writable = None })
+            | "string" -> Array String
+            | "int" -> Array Int
+            | "long" -> Array Long
+            | "float" -> Array Float
+            | "double" -> Array Double
+            | "boolean" -> Array Boolean
+            | _ -> failwith "Invalid CWL type"
+        )
+
+    let cwlTypeDecoder: (YAMLiciousTypes.YAMLElement -> CWLType) =
+        Decode.object (fun get ->
+            let cwlType = 
+                get.Required.Field 
+                    "type" 
+                    (
+                        fun value ->
+                            match value with
+                            | YAMLElement.Value v | YAMLElement.Object [YAMLElement.Value v] -> Some v.Value
+                            | YAMLElement.Object o -> None
+                            | _ -> failwith "Unexpected YAMLElement"
+                    )
+            match cwlType with
+            | Some t ->
+                match t with
+                | "File" -> File (FileInstance ())
+                | "Directory" -> Directory (DirectoryInstance ())
+                | "Dirent" -> Dirent { Entry = ""; Entryname = None; Writable = None }
+                | "string" -> String
+                | "int" -> Int
+                | "long" -> Long
+                | "float" -> Float
+                | "double" -> Double
+                | "boolean" -> Boolean
+                | "File[]" -> Array (File (FileInstance ()))
+                | "Directory[]" -> Array (Directory (DirectoryInstance ()))
+                | "Dirent[]" -> Array (Dirent { Entry = ""; Entryname = None; Writable = None })
+                | "string[]" -> Array String
+                | "int[]" -> Array Int
+                | "long[]" -> Array Long
+                | "float[]" -> Array Float
+                | "double[]" -> Array Double
+                | "boolean[]" -> Array Boolean
+                | "stdout" -> Stdout
+                | "null" -> Null
+                | _ -> failwith "Invalid CWL type"
+            | None -> 
+                let cwlTypeArray = get.Required.Field "type" cwlArrayTypeDecoder
+                cwlTypeArray
+        )
+
+    let outputArrayDecoder: (YAMLiciousTypes.YAMLElement -> Output[]) =
+        Decode.object (fun get ->
+            let dict = get.Overflow.FieldList []
+            [|
+                for key in dict.Keys do
+                    let value = dict.[key]
+                    let outputBinding = outputBindingDecoder value
+                    let cwlType = cwlTypeDecoder value
+                    { Name = key; Type = cwlType; OutputBinding = Some outputBinding }
+            |]     
+        )
+    
+    let outputsDecoder: (YAMLiciousTypes.YAMLElement -> Output[]) =
+        Decode.object (fun get ->
+            let outputs = get.Required.Field "outputs" outputArrayDecoder
+            outputs
+        )
+
+    let requirementArrayDecoder: (YAMLiciousTypes.YAMLElement -> Requirement[]) =
+        Decode.array 
+            (
+                Decode.object (fun get ->
+                    let cls = get.Required.Field "class" Decode.string
+                    match cls with
+                    | "InlineJavascriptRequirement" -> InlineJavascriptRequirement
+                    | "SchemaDefRequirement" -> SchemaDefRequirement [||]
+                    | "DockerRequirement" ->
+                        let dockerReq = {
+                            DockerPull = get.Optional.Field "dockerPull" Decode.string
+                            DockerFile = Some ""
+                            DockerImageId = get.Optional.Field "dockerImageId" Decode.string
+                        }
+                        DockerRequirement dockerReq
+                    | "SoftwareRequirement" -> SoftwareRequirement [||]
+                    | "InitialWorkDirRequirement" -> InitialWorkDirRequirement [||]
+                    | "EnvVarRequirement" -> EnvVarRequirement {EnvName = ""; EnvValue = ""}
+                    | "ShellCommandRequirement" -> ShellCommandRequirement
+                    | "ResourceRequirement" -> ResourceRequirement (ResourceRequirementInstance())
+                    | "NetworkAccess" -> NetworkAccessRequirement
+ 
+                )
+            )
+
+    let requirementsDecoder: (YAMLiciousTypes.YAMLElement -> Requirement[]) =
+        Decode.object (fun get ->
+            let requirements = get.Required.Field "requirements" requirementArrayDecoder
+            requirements
+        )
+
+    let hintsDecoder: (YAMLiciousTypes.YAMLElement -> Requirement[]) =
+        Decode.object (fun get ->
+            let requirements = get.Required.Field "hints" requirementArrayDecoder
+            requirements
+        )
+
+    let inputBindingDecoder: (YAMLiciousTypes.YAMLElement -> InputBinding option) =
+        Decode.object(fun get ->
+            let outputBinding = 
+                get.Optional.Field 
+                    "inputBinding" 
+                    (
+                        Decode.object (fun get' ->
+                            {
+                                Prefix = get'.Optional.Field "prefix" Decode.string
+                                Position = get'.Optional.Field "position" Decode.int
+                                ItemSeparator = get'.Optional.Field "itemSeparator" Decode.string
+                                Separate = get'.Optional.Field "separate" Decode.bool
+                            }
+                        )         
+                    )
+            outputBinding
+        )
+
+    let inputArrayDecoder: (YAMLiciousTypes.YAMLElement -> Input[]) =
+        Decode.object (fun get ->
+            let dict = get.Overflow.FieldList []
+            [|
+                for key in dict.Keys do
+                    let value = dict.[key]
+                    let inputBinding = inputBindingDecoder value
+                    let cwlType = cwlTypeDecoder value
+                    { Name = key; Type = cwlType; InputBinding = inputBinding }
+            |]     
+        )
+    
+    let inputsDecoder: (YAMLiciousTypes.YAMLElement -> Input[]) =
+        Decode.object (fun get ->
+            let outputs = get.Required.Field "inputs" inputArrayDecoder
+            outputs
+        )
+
+    let decodeAll =
+        let yamlCWL = Decode.read exampleCWL
+        CWL(
+            cwlVersion = Decode.object (fun get -> get.Required.Field "cwlVersion" Decode.string) yamlCWL,
+            cls = 
+                Decode.object (fun get ->
+                    match get.Required.Field "class" Decode.string with
+                    | "Workflow" -> Workflow
+                    | "CommandLineTool" -> CommandLineTool
+                    | "ExpressionTool" -> ExpressionTool
+                    | _ -> failwith "Invalid class"
+                ) yamlCWL
+                ,
+            outputs = outputsDecoder yamlCWL,
+            inputs = inputsDecoder yamlCWL,
+            //baseCommand = Decode.object (fun get -> get.Optional.Field "baseCommand" (Decode.array Decode.string)) yamlCWL,
+            requirements = requirementsDecoder yamlCWL,
+            hints = hintsDecoder yamlCWL
+        )
\ No newline at end of file
diff --git a/src/CWL/Encode.fs b/src/CWL/Encode.fs
new file mode 100644
index 00000000..e69de29b