I'm getting an assertion failed error in NBFFICallout The debugger is point to this line: self assert: type loader notNil. <==========AssertionFailure:AssertionFailed ^ type when I run this code: +++++++++++++++ myBytes := ByteArray new: 20. (GMPfrWrapper new) test4: myBytes withLength: 20. ++++++++++++++++ GMPfrWrapper>> test4:bytes withLength: length <primitive: #primitiveNativeCall module: #NativeBoostPlugin> ^ NBFFICallout cdecl: #( int _ByteTest(ulong length, NBByteArrayPtr byteArray) ) module: '/Users/lawsonenglish/Library/Developer/Xcode/DerivedData/Mandelbrot_Set-budpkxrcvoxdiocqojopadbgogzi/Build/Products/Debug/libMandelDraw.dylib' ++++++++++++++++++ I'ved checked with nm "/Users/lawsonenglish/Library/Developer/Xcode/DerivedData/Mandelbrot_Set-budpkxrcvoxdiocqojopadbgogzi/Build/Products/Debug/libMandelDraw.dylib" and get: 00000e30 T _ByteTest ... I can load the file by doing: string := FileStream readOnlyFileNamed:'/Users/lawsonenglish/Library/Developer/Xcode/DerivedData/Mandelbrot_Set-budpkxrcvoxdiocqojopadbgogzi/Build/Products/Debug/libMandelDraw.dylib' do: [:stream| stream binary. stream contents]. Suggestions? Thanks, L -- Squeak from the very start (introduction to Squeak and Pharo Smalltalk for the (almost) complete and compleate beginner). https://www.youtube.com/playlist?list=PL6601A198DF14788D&feature=view_all