Yup. OpenWRT uses (patched!) Linux, but with a much smaller set of libraries/utilities to fit in small storage footprints. I'm using ye normal FreeBSD libc, libcrypto, etc - things are pretty big.

It could be fun to take something like the BSD kernel and an alternative BSD licenced userland to make a much smaller footprint device, but I don't have the energy to /also/ do that.

If someone would like to do that then please do step up and do it! I wouldn't even mind if the FreeBSD wifi stack and Atheros MIPS support was ported back to NetBSD and NetBSD was used for this purpose.