[durin42]

Go isn't really a huge win for hg, and it doesn't support being used as a shared library, so we couldn't easily use it as a replacement for C for native extensions. main() has to be in Go, and even then you've got two GCs in the mix which is not great.

[neandrake]

Using rust for a shared library implementation seems like it would mean a big improvement for mercurial's tooling in the long run. Right now the options are command line invocation or using the python library (effectively puts a requirement on implementation). Though I'm not sure the integrations I'm aware of[0] would benefit from a shared library.

[0] https://secure.phabricator.com/T9548