Show HN: Chunk sidecars for validating agent-generated code before pushing to CI

CircleCI released Chunk sidecars, an open-source tool that runs lightweight microbuilds in a Firecracker microVM to validate agent-generated code before commit or push. It auto-detects a project's stack and test commands, mirroring the CI environment to catch failures earlier. Internal tests showed ~27 second average microbuilds and reduced billable compute versus full CI runs.