Everything that happens between the push and the green check
Four features, one CLI step. Three of them are free on public repositories; shard balancing comes with the Team plan.
Free for open source
Test selection
On every pull request, Bellwether walks the diff against a recorded map and runs only the tests that can reach a changed file. Median suites drop to 13 percent of their size.
How it works
Free for open source
Flaky test quarantine
A test that fails and then passes on the same commit is rerun in isolation. If it disagrees with itself, it stops blocking merges and moves to a quarantine list with both runs attached.
How it works
Free for open source
The skip report
Every test Bellwether leaves out is listed with the reason it was safe to leave out. Ask about any test on any commit and get one of eight plain answers.
How it works
Team, from $24 a seat
Shard balancing
The selected tests are split across your parallel machines by each test’s recorded duration, so every shard finishes within seconds of the others. No shard lists to maintain.
How it worksHow it compares
A 3,000-test suite that takes 38 minutes on one machine, handled three ways.
| What you get | Bellwether | Run everything | Manual sharding |
|---|---|---|---|
| Wait per push | 6–9 minutes | The full suite, 38 minutes | Suite ÷ shards, about 12 minutes on 4 |
| CI minutes billed | About 15% of the suite | 100% of the suite | 100% plus setup on every shard |
| Catches what the change can break | Yes, plus a full run nightly | Yes | Yes |
| Flaky tests | Quarantined with both runs attached | Block the merge until retried | Block the merge until retried |
| Upkeep | None, the map rebuilds itself | None | Rebalancing shard lists by hand |
| Cost | From $0 for open source, $24 a seat | Your CI bill | Your CI bill plus engineer hours |
See the selection on your own repository.
Install the CLI, record one full run and read the skip report before you let it skip anything.