Merging this PR will not alter performance

✅ 9 untouched benchmarks

_{Comparing add-towncrier-to-manage-changelogs (a71e539) with main (0d9f0c5)}

Greptile Summary

This PR introduces towncrier for automated changelog management across the monorepo. It adds a shared [tool.towncrier] config in the root pyproject.toml, creates news/ stub directories for every package, documents the fragment workflow in CONTRIBUTING.md, and adds a GitHub Actions check (changelog.yml) that detects which packages were changed and verifies the presence of a corresponding news fragment, with a skip-changelog label escape hatch.

Confidence Score: 5/5

Safe to merge — tooling/infra change only, no application logic modified

All findings are P2 style suggestions; the workflow logic is sound (correct monorepo detection, safe empty-array handling, proper set -euo pipefail scoping), and the towncrier config aligns with the monorepo docs.

.github/workflows/changelog.yml — minor script-injection style issue on line 22

Important Files Changed

Flowchart

%%{init: {'theme': 'neutral'}}%%
flowchart TD
    A([PR opened / updated]) --> B{skip-changelog\nlabel present?}
    B -- Yes --> Z([CI passes — skip])
    B -- No --> C[git diff --name-only\norigin/main...HEAD]
    C --> D{reflex/ changed?}
    D -- Yes --> E[Add '.' to affected]
    D -- No --> F{packages/**/src/ changed?}
    E --> F
    F -- Yes --> G[Add pkg_dir to affected]
    F -- No --> H{affected.txt empty?}
    G --> H
    H -- Yes --> Z
    H -- No --> I[For each pkg_dir:\ntowncrier check\n--config pyproject.toml\n--dir pkg_dir]
    I --> J{All checks pass?}
    J -- Yes --> K([CI passes])
    J -- No --> L([CI fails:\nmissing news fragment])

_{Reviews (1): Last reviewed commit: "add towncrier to manage changelogs" | Re-trigger Greptile}