I just had Kimi K2.7-code rebase my Fil-C OpenSSL patch from 3.3.1 to 3.5.7 with quite bare bones instructions and it seems to have worked.

177KB patch, so it's not a small change. The patch did not apply cleanly initially; the agent had to do nontrivial work.

I just showed it the patch against 3.3.1, what command to use to build, and the path to 3.5.7 along with a link to the documentation of the change (https://fil-c.org/constant_time_crypto).

Note, I use my own coding agent (T800, which isn't public, and was previously well tested and tuned for K2.5).

I think this cost me between $5 and $10 in API usage.

(EDIT: OpenSSL, not OpenSSH)