I suspect they just use no_std whenever its applicable https://github.com/facebook/buck2/commit/4a1ccdd36e0de0b69ee185fc9dae8c9d9dfdf3de https://github.com/fac

I suspect they just use no_std whenever its applicable https://github.com/facebook/buck2/commit/4a1ccdd36e0de0b69ee185fc9dae8c9d9dfdf3de https://github.com/facebook/buck2/commit/4a1ccdd36e0de0b69ee... https://github.com/facebook/buck2/commit/bee72b29bc9b67b59ba775ce65057f122c75aa70 https://github.com/facebook/buck2/commit/bee72b29bc9b67b59ba... Turn out if you have strong control over the compiler and linker instrumentations, there are a lot of ways to optimize binary size