AI coding has made CI a bottleneck, so we reworked ours to keep up
- ID
- 27206
- Status
- summarized
- Published
- 22 Sep 2026, 3:23 AM
- Fetched
- 24 Sep 2026, 4:22 AM
- Provider
- Hacker News
- Category
- dev-community
- Original URL
- https://linear.app/now/ci-bottleneck-reworked
- Source URL
- https://hnrss.org/best
Summary
- Score
- 8.0
- Created
- 24 Sep 2026, 4:23 AM
- Tags
- Audience
- developersvibe_coderssaas_founders
What happened
Linear's engineering team reworked their CI pipeline because AI coding agents accelerated code production faster than validation could keep up, making CI a bottleneck. Despite test suites nearly quadrupling since January, they cut PR wait time from 6+ minutes to ~5 minutes and halved runner time per test by moving off GitHub Actions to faster third-party runners (34% faster jobs), switching to tsgo native TypeScript compiler (73% faster tsc), rewriting lint rules to drop TypeScript type dependency (68% faster API lint), and adopting Oxlint.
Why it matters
If you're using AI agents to ship code faster, your CI costs and wait times will scale with throughput, not team size. The highest-leverage moves here were infrastructure-level (switching runners, swapping compilers) rather than test-level micro-optimization—evaluate whether your CI runner choice and toolchain are the real bottleneck before optimizing individual tests.
Discussion angle
As AI agents generate more PRs, CI becomes the new bottleneck—what's the cost-per-PR math for your team, and at what point does migrating off GitHub Actions to dedicated runners pay for itself?