Skip to content

Testing

Test sharding

Quick answer

Test sharding splits a test suite into subsets that run in parallel on separate machines.

Test sharding splits a test suite into subsets that run in parallel on separate machines.

Why it matters

It is the most reliable way to cut a long suite, but naive splitting by file count leaves stragglers. Shard by historical duration instead.

Your next build could be twice as fast, at half the price

Start free. Migrating away is the same one line, and we publish that diff too.