TL;DW: This error means you have a static library (that's already being "pasted" into your app binary) but try to embed it in the app bundle. Remove the embedding to fix this, linking suffices. The full write-up: https://christiantietze.de/posts/2021/07/mach-o-0x72613c21-static-library/ The Apple TN2435: https://developer.apple.com/library/archive/technotes/tn2435/_index.html