Hacktoberfest 2026: the issues maintainers tagged for October, open and beginner-friendly. Browse Hacktoberfest issues

De-fork spike S1: baseline metrics + upstream-merge replay harness

Open
#1,010 0 comments 0 reactions 0 assignees View on GitHub

Nobody has claimed this yet.

Assessment

Difficulty
5/5
Estimated time
Over a week
Newbie friendliness
35/100
Issue type
Feature
Clarity
Mostly clear
Activity status
Quiet
Tech stack
git, typescript
Domain
ci-cd, devtools, tooling

Research direction

Start by reading docs/internal/2026-07-18-defork-spike-spec.md and the existing marker-guard job. Then inspect script/upstream/taxonomy.ts, census.ts, divergence.ts, and replay.ts to understand the required baselines, parsing, diff, and merge behavior. Done means the committed baselines, empty exemptions file, CI ratchet wiring, first v1.18.3 replay, regenerated divergence numbers, and feasibility-plan addendum are present.

Written by the indexing model from the issue text.

Description

Stage S1 of the de-fork spike (spec: docs/internal/2026-07-18-defork-spike-spec.md, Codex-consensus-approved rev 4).

Deliverables, all in script/upstream/:

  • taxonomy.ts — 3-bucket classification (upstream_shared / fork_owned / fork_added_outside_boundary) against the pinned v1.17.9 upstream tree, upstream-existence precedence, 10-path .opencode/ overlap pinned by a generated oracle test.
  • census.ts — stack-based marker-block parser, category table, versioned JSON envelope, --summary/--json/--check/--diff-budget modes; multiset ratchet with quantity-scoped committed exemptions.
  • divergence.ts — files/hunks/lines vs upstream base per bucket, pinned diff options.
  • replay.ts — explicit-base three-way merge via git merge-tree --write-tree --merge-base (no working-tree mutation), conflict taxonomy, census attribution with SHA-mismatch rejection. First real run vs v1.18.3.
  • Committed baselines + empty exemptions file + CI ratchet wiring into the existing marker-guard job.
  • Regenerated headline divergence numbers + feasibility-plan addendum.

Zero product-behavior risk (tooling/tests/CI only). Mergeability gates per spec §0.

Dominant language
TypeScript
Stars
813
Forks
134
Avg merge
2d 3h
Merged PRs (30d)
65

Contributor guide

Open the contributing guide

First steps

  1. Read the whole issue, then the project's contributing guide.
  2. Comment on the issue to say you are picking it up — it saves two people doing the same work.
  3. Fork the repository and make your change on a branch.
  4. Open a pull request that references the issue number.

More from AltimateAI/altimate-code

All issues in AltimateAI/altimate-code

Similar issues

More TypeScript issues

Get new issues in your inbox

A short digest of beginner-friendly GitHub issues.