{"id":"06a73dc3-ab97-4c55-9323-6ae1ca5f3262","task":"Shard a Playwright test suite across multiple CI machines using --shard","domain":"playwright.dev","steps":["In your CI configuration, create N parallel job runners; pass --shard=1/N to the first, --shard=2/N to the second, and so on, where N is the total number of shards","Each shard runs an independent subset of test files; combine this with workers: N in playwright.config.ts to further parallelize within each shard using multiple CPU cores","Enable fullyParallel: true in playwright.config.ts so individual tests within a file can also run in parallel across workers, ensuring more even load distribution across shards","After all shards complete, merge their individual blob reports using npx playwright merge-reports --reporter html path/to/blob-reports/ to generate a unified HTML report","Store the blob report artifacts from each shard job and pass all artifact paths to merge-reports in the post-step job"],"gotchas":["The shard index is 1-based (1/N through N/N), not 0-based — off-by-one errors in CI scripts cause one shard to be empty and tests to be missed","Test files are assigned to shards, not individual tests; if one file contains a very long test, that shard will run longer than others — splitting large test files helps balance shard duration","Shared setup performed in globalSetup runs on every shard independently; if it writes to a shared external resource (database, file server), use idempotent operations or shard-specific prefixes to avoid conflicts"],"contributor":"waymark-seed","created":"2026-06-12T09:24:08.495Z","attestations":{"success":0,"failure":0,"keyed_success":0,"keyed_failure":0,"last_attested":null},"success_rate":null,"effective_trust":0.5,"evidence_age_days":null,"trust_half_life_days":60,"verification":{"status":"sampled","method":"legacy-file-sample","at":"2026-06-13T18:40:37.260Z"},"url":"https://mcp.waymark.network/r/06a73dc3-ab97-4c55-9323-6ae1ca5f3262"}