diff --git a/RollbarNotifier/Sources/RollbarCrash/Util/RollbarCrashMachineContext.c b/RollbarNotifier/Sources/RollbarCrash/Util/RollbarCrashMachineContext.c
index d3f55d6e..199186de 100644
--- a/RollbarNotifier/Sources/RollbarCrash/Util/RollbarCrashMachineContext.c
+++ b/RollbarNotifier/Sources/RollbarCrash/Util/RollbarCrashMachineContext.c
@@ -39,7 +39,8 @@
 #ifdef __arm64__
     #define UC_MCONTEXT uc_mcontext64
 
-typedef ucontext64_t SignalUserContext;
+    #include <sys/_types/_ucontext64.h>
+    typedef ucontext64_t SignalUserContext;
 #else
     #define UC_MCONTEXT uc_mcontext
     typedef ucontext_t SignalUserContext;