I just installed it via homebrew on macos and used the anthropic-compatible custom provider option to configure it to use with deepseek-flash and then used this setup to build a quick rust project that I had been deferring for months - total cost: 1 us cent and under 10 minutes total for setup and etc. Thank you for making such a lean and clean option.
This is cool! There were a few rust attempts I played around with last year, but they all seemed to fizzle out in favor of everything running on top of js or python.
I know that Google just launched a go version a couple months ago, but I haven't really spent any time with it, because well, gemini isn't really useful to me right now.
The thing I constantly ran into with using non-platform (ie. claude code or codex) agents is that even though their tool call API seems flexible, they've finetuned these "agentic" models around their specific agents. Opus is the worst I've seen about this. It really wants to use specific bash tools and if you restrict or hide it, it'll start writing python code to call into bash to do it.
Generally, the models seem to adapt really well. I am using GPT models in hax a lot, and they have no trouble whatsoever using hax tools instead of their "native" codex tools.
Also since hax tools are just "read", "edit", "write", "bash" and "task_wait", it would be expected that the models would use one-off scripts to achieve their goals (either shell scripts, or python scripts, etc).
> I don't understand why anyone would still start a new software project in C today, given the long track record of mistakes developers can make in it.
If you think that unintended consequences can result from using C, boy do I have some news for you for "programmers" from 2026.
I just installed it via homebrew on macos and used the anthropic-compatible custom provider option to configure it to use with deepseek-flash and then used this setup to build a quick rust project that I had been deferring for months - total cost: 1 us cent and under 10 minutes total for setup and etc. Thank you for making such a lean and clean option.
Would love to hear more about the decision to create the terminal in C? Also what did you use to record your demo video? It looks awesome!
The main reason to use C is that it's the easiest way to achieve minimal resource footprint. Also it's the language I know really well already.
The demo was recorded with asciinema.
asciinema is so good! Love seeing the player on the site.
This is cool! There were a few rust attempts I played around with last year, but they all seemed to fizzle out in favor of everything running on top of js or python.
I know that Google just launched a go version a couple months ago, but I haven't really spent any time with it, because well, gemini isn't really useful to me right now.
The thing I constantly ran into with using non-platform (ie. claude code or codex) agents is that even though their tool call API seems flexible, they've finetuned these "agentic" models around their specific agents. Opus is the worst I've seen about this. It really wants to use specific bash tools and if you restrict or hide it, it'll start writing python code to call into bash to do it.
https://github.com/vinhnx/vtcode (not affiliated, just saw someone posting it here) and of course Codex are still active.
Generally, the models seem to adapt really well. I am using GPT models in hax a lot, and they have no trouble whatsoever using hax tools instead of their "native" codex tools.
Also since hax tools are just "read", "edit", "write", "bash" and "task_wait", it would be expected that the models would use one-off scripts to achieve their goals (either shell scripts, or python scripts, etc).
I know the Pi [0] folks had some trouble with newer models [1].
[0]: https://pi.dev/
[1]: https://lucumr.pocoo.org/2026/7/4/better-models-worse-tools/
A minimalist, terminal-native coding agent written in C is such a clean approach to lightweight local tooling. Love the tech stack choice.
Note to be confused with Haxe: https://haxe.org/
If it's minimalist and written in C why does it have such specific system requirements?
Probably because of the 'minimalist' qualifier.
I just built and installed this harness on my MacBook Pro and am very happy with its clean, fast performance with local models and llama.cpp.
Well done, Oleksandr!
I don't understand why anyone would still start a new software project in C today, given the long track record of mistakes developers can make in it.
What are your thoughts on JavaScript?
> I don't understand why anyone would still start a new software project in C today, given the long track record of mistakes developers can make in it.
If you think that unintended consequences can result from using C, boy do I have some news for you for "programmers" from 2026.
Because C is the best.
oh cool! how do I contribute? :)
As usual, I suppose :) - by filing bug reports, and opening pull requests.
Nice work! Thank you for sharing it.
This looks really interesting! Excited to give it a try.