perf(ci): Increase Jest shards from 4 to 8 for faster CI#114388
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NicoHinderling merged 1 commit intomasterfrom Apr 30, 2026
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perf(ci): Increase Jest shards from 4 to 8 for faster CI#114388NicoHinderling merged 1 commit intomasterfrom
NicoHinderling merged 1 commit intomasterfrom
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Increase Jest CI shards from 4 to 8 to reduce wall-clock time for frontend tests. Current state: 4 shards run ~6-8 minutes each, with the slowest shard (typically shard 3) bottlenecking at ~7-8 min wall clock. Total test execution across all shards sums to ~25 minutes. With 8 shards, each shard runs ~3 min of tests + ~22s setup overhead, cutting wall clock from ~8min to ~4min. Compute cost stays roughly the same (8×4min ≈ 4×8min), with minor additional overhead from 4 extra checkout/setup steps. Also fixes a bug in `jest.config.ts` where the round-robin leftover distribution was hardcoded to `i % 4` instead of `i % nodeTotal`, which would have caused imbalanced shard assignment with any non-4 shard count.
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Increase Jest CI shards from 4 to 8 to reduce wall-clock time for frontend tests.
Current state: 4 shards run ~6-8 minutes each, with the slowest shard (typically shard 3) bottlenecking at ~7-8 min wall clock. Total test execution across all shards sums to ~25 minutes.
With 8 shards, each shard runs ~3 min of tests + ~22s setup overhead, cutting wall clock from ~8min to ~4min. Compute cost stays roughly the same (8×4min ≈ 4×8min), with minor additional overhead from 4 extra checkout/setup steps.
Also fixes a bug in
jest.config.tswhere the round-robin leftover distribution was hardcoded toi % 4instead ofi % nodeTotal, which would have caused imbalanced shard assignment with any non-4 shard count.