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Chunk sidecars - Validate agent-generated code before it ever reaches CI

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AI agents write code fast. Validation still happens after the push — by then the context is gone. Chunk sidecars run scoped microbuilds before commit, in a real CI mirror. Auto-detects your stack. ~27s average vs ~5 min billable compute for a full run. 3x–5x fewer tokens in retry loops. If something fails, the agent iterates before anything reaches shared CI. Run chunk init. Works with Claude Code, Codex, Cursor, or custom agents. Free for all CircleCI users.

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Maker
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Hey Product Hunt 👋 One thing that became obvious while experimenting with agent workflows internally: the code generation is becoming the easy part. The expensive part is when validation happens after the push, CI fails, and now the agent has already moved on and lost the useful context around the change. We’re also seeing this show up in the broader data. In our 2026 State of Software Delivery report, build volume increased 59% year over year while main branch success rates dropped to a 5-year low. That’s why we built Chunk sidecars. They run lightweight microbuilds against environments that mirror your CI stack while the agent is still iterating on the code. Feedback comes back in under 60 seconds, so failures get caught before they ever hit shared CI. Here’s a short demo: Would love feedback from people already experimenting with AI-assisted development workflows!

This is a strong wedge if the sidecar output is easy to review inside a normal PR. For agent-generated code, the hard part is not only catching failures, but making the failure cheap enough that developers actually read it before CI.

I’d be curious whether Chunk sidecars can show “why this changed” next to tests, touched files, and risk areas, rather than only a pass/fail validation result.

Maker

 Tnx for your great thoughts and feedback! The current premise for Chunk sidecars is that it can validate and trigger for (agent)fixes autonomously and transparently, before even hitting the CI, and thus not polluting the PR with unnecessary info for a human reviewer. Though I can imagine that passing some kind of summary/event-log to the "outer loop" CI pipeline with issues and fixes might be valuable for a PR review. Thanks for sharing!