CodeCaster

Inspiration

What it does

How we built it

Challenges we ran into

Accomplishments that we're proud of

What we learned

What's next for CodeCaster

CodeCaster is a live-coding hackathon MVP for the Codex × TwitchCon challenge. Viewers type !ship or !fix in Twitch chat. A Node bot listens on IRC, queues one patch job at a time (with per-user rate limits), and runs a sandboxed agent that proposes a small unified diff against a toy React + Express app—hard-capped at one file and about fifty lines changed.

An OBS Browser Source overlay shows the last command, a short diff summary, and a green or red status while the job runs and smoke-tests. The streamer stays in control: Accept applies the patch to the toy app; Reject (or a timeout) discards the sandbox with no change. No Twitch Extension—just IRC chat, local Node services, and a transparent overlay—so the demo works on free tiers and offline mock mode when Twitch credentials are not configured.

How we built / Codex: npm workspaces monorepo—apps/toy (React + Vite + Express), apps/bot (Twitch IRC via tmi.js), apps/agent (sandbox → LLM/unified diff → git apply → smoke), apps/overlay (OBS). npm run simulate drives !ship without Twitch. Real Codex session ID recorded: 01a176d5-3063-7842-a2d6-7e78bdd4fc34.

Built With

• browser
• obs
• openai
• twitch