musl libc

musl is lightweight, fast, simple, free, and strives to be correct in the sense of standards-conformance and safety.

Home page: https://www.musl-libc.org/
Source code: https://git.musl-libc.org/cgit/musl/tree
Comparison with other libcs: http://www.etalabs.net/compare_libcs.html

>>6
Linux is not an operating system.