## Thinking Path
> - Paperclip is the open source app people use to manage AI agents for
work.
> - The PR workflow runs the server vitest suite across sharded runners
because the suite is pinned to one worker.
> - In successful PR run 30930345729 (2026-08-04), shard `server (3/4)`
took 311 seconds of wall time and was the slowest check in the run.
> - The suite has grown to about 946 seconds of serial vitest time, but
the duration manifest was last sampled on 2026-08-01 at about 882
seconds.
> - This pull request refreshes the per-suite duration manifest from
that run's logs and splits the lane into five shards.
> - The benefit is a shorter PR critical path: each shard carries about
196 seconds of suite time, level with the other lanes.
## Linked Issues or Issue Description
Refs #10663 (previous split of this lane into four shards).
Related: #10923 splits the separate serialized-suites lane into five
shards. Both PRs touch `.github/workflows/pr.yml` in different matrix
blocks; whichever merges second needs a trivial rebase.
**What existing behavior does this improve?**
The `general-server` vitest lane runs in four shards with a duration
manifest sampled on 2026-08-01.
**Current behavior**
In PR run 30930345729, shard 3/4 ran for 311 seconds (273 seconds in the
test step) and was the longest check in the run. The suite now totals
about 946 seconds of serial vitest time.
**Proposed behavior**
Run the same suite set in five shards, balanced with a per-suite
duration manifest refreshed from that run's shard logs (279 suites
measured by diffing consecutive completion timestamps).
**Reason and benefit**
The refreshed LPT partition balances at about 196 seconds of suite time
per shard (about 240 seconds per job), level with the other PR lanes. No
test coverage is lost.
**Breaking changes**
None. The change only alters the CI partition size and the duration
manifest.
## What Changed
- Bump the `general-server` shard matrix in `.github/workflows/pr.yml`
from four to five shards.
- Refresh `scripts/general-server-shard-durations.json` from the
2026-08-04 run's shard logs.
- Update `SHARD_COUNT` in
`scripts/__tests__/run-vitest-stable-shard.test.mjs` to five.
## Verification
- `node --test scripts/__tests__/run-vitest-stable-shard.test.mjs` — 9/9
pass, including the complete non-overlapping partition proof and the
duration-balance check.
- `node --test scripts/__tests__/release-verify-workflow.test.mjs` — 2/2
pass.
- `node --test scripts/__tests__/e2e-shard.test.mjs` — 7/7 pass.
- A 5-way dry-run partition covers all suites exactly once with equal
projected weights.
## Risks
- Low risk. The change only alters CI partition size and duration
weights; the suite set is unchanged.
- One more runner is used per PR run for this lane.
- Stale duration weights degrade gracefully: suites missing from the
manifest get the median weight.
## Model Used
- Claude (Anthropic), Claude Code CLI, model ID `claude-fable-5`,
extended thinking with tool use enabled.
## Checklist
- [x] I have included a thinking path that traces from project context
to this change
- [x] I have specified the model used (with version and capability
details)
- [x] I have checked ROADMAP.md and confirmed this PR does not duplicate
planned core work
- [x] I have searched GitHub for duplicate or related PRs and linked
them above
- [x] I have either (a) linked existing issues with `Fixes: #` / `Closes
#` / `Refs #` OR (b) described the issue in-PR following the relevant
issue template
- [x] I have not referenced internal/instance-local Paperclip issues or
links (only public GitHub `#NNN` / `github.com/paperclipai/paperclip`
URLs)
- [x] My branch name describes the change (e.g. `docs/...`, `fix/...`)
and contains no internal Paperclip ticket id or instance-derived details
- [x] I have run tests locally and they pass
- [x] I have added or updated tests where applicable
- [x] I have updated relevant documentation to reflect my changes
(workflow comments explain the new shard math)
- [x] I have considered and documented any risks above
- [ ] All Paperclip CI gates are green
- [ ] Greptile is 5/5 with no open P2s, recommendations, or follow-ups
- [x] I will address all Greptile and reviewer comments before
requesting merge
Co-authored-by: Claude <claude@paperclip.ing>
Co-authored-by: Paperclip <noreply@paperclip.ing>
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