- All playbooks
- Run the whole test suite under a leak sanitizer with a curated suppression list
Run the whole test suite under a leak sanitizer with a curated suppression list
A sanitizer lane runs every test in CI, and each leak it reports is fixed or listed with a reason.
Company examples
How Anthropic used this technique
Read what Anthropic changed and follow the original sources.
Run the whole test suite under a leak sanitizer with a curated suppression list
Bun's CI runs the entire test suite under LeakSanitizer with a curated suppression list. After an allocator change let the sanitizer see every heap allocation, every leak it reported was fixed. The sanitizer test agents moved to machines with more memory, and each test gets a wider timeout in the sanitizer lane.
- Use it when
- A repository with native code (C, C++, Rust or Zig) or another language with a leak or memory checker runs its tests only in regular builds.
- Before applying it
- The sanitizer lane runs beside the regular lanes with its own machine size and per-test timeout, and each suppression carries a written reason.
Company Playbooks
- Read Anthropic’s playbookRun only affected tests
- Read DoorDash’s playbookRun build and test in parallel, sharded across CI agents
- Read Linear’s playbookBenchmark the same job on faster hardware
- Read Mastra’s playbookStarSling runners for the slowest test workflow
- Read OpenAI’s playbookRank CI fixes by the minutes they save
- Read Ramp’s playbookMove a CPU-bound test suite to a faster CPU
- Read Shopify’s playbookLet an agent iterate against one CI metric
- Read Spotify’s playbookBuild arm64 on native arm64 runners
- Read Stripe’s playbookRun only the tests a change can reach
- Read Uber’s playbookBuild the merge-queue speculations most likely to be needed