Propagate template main into forked store repos

You may be running autonomously across many repos. Do not ask questions — decide, act, and report. If one store fails, record it and move on to the next.

Architecture facts (do not rediscover these)

• Store repos are yns-store-<subdomain> in the GitHub org yns-cx-tenants (staging / yns.cx) or yns-store-tenants (production / yns.store). Access via gh.
• Store repos share no git history with this template. Provisioning copies template files into a fresh repo without upstream parents (see the platform's src/lib/sandbox/fork-builder.ts). Never attempt git rebase/git merge against the template — this skill reconciles content, file by file.
• Stores may have been seeded from a theme-* branch, and Elliot edits files freely afterwards. The only files Elliot cannot touch are the managed paths (proxy.ts, lib/track.tsx, instrumentation-client.ts — the platform's MANAGED_STOREFRONT_PATHS): the platform's commit script restores those from the store repo's own origin/main on every save, so landing the template's version on the store's main IS the propagation mechanism for them.
• Pushing to a store repo's main triggers a production redeploy of that tenant storefront, and it is safe with respect to live builder sandboxes: their save script fetches and rebases onto FETCH_HEAD, aborting cleanly on conflict.
• .env* files are per-store secrets. Never read, modify, or commit them.

Inputs

• Optional: a list of store subdomains (e.g. base celeste) and/or the org to target. Default: staging org, all builder stores.
• Enumerate builder stores from the platform DB when available (source of truth): SELECT subdomain FROM stores WHERE builder_config IS NOT NULL; — otherwise gh repo list <org> --limit 200 --json name and strip the yns-store- prefix.

Per-store algorithm

Work from a checkout of this template repo with full history and all branches fetched (git fetch origin "+refs/heads/*:refs/remotes/origin/*"). Clone each store repo into a temp dir (gh repo clone <org>/yns-store-<subdomain> <tmp> -- --depth=1).

The decision rule for every path is "has the store ever customized this file?", answered by blob-hash comparison against the template origin/main history:

# all historical blob hashes of a path on template main (cache per path):
git -C <template> log origin/main --format=%H -- <path> \
  | while read sha; do git -C <template> rev-parse -q --verify "$sha:<path>"; done | sort -u
# the store's current blob:
git -C <store> hash-object <path>

Matching only a theme-* blob (not any main-history blob) counts as customized — theme identity must never be flattened onto main's look.

Then, per path:

1. Managed paths (proxy.ts, lib/track.tsx, instrumentation-client.ts): overwrite with template main's version unconditionally.
2. Path exists in template main and the store's copy differs: if the store blob matches some main-history blob → replace with template main's version. Otherwise → leave it, record as skipped (customized).
3. Path exists in the store but not in template main (template deleted it): if the store blob matches some main-history blob → delete it. Otherwise → leave, record as skipped (customized, template deleted).
4. Store-created paths (never existed on template main): untouched, not reported.
5. Special cases — never blanket-copied:
   • package.json: reconcile dependencies with jq — for every key in the template's dependencies/devDependencies, set the template's version; drop store keys absent from template main whose version spec matches some main-history spec (i.e. the template removed them); keep store-added deps. Leave scripts and the rest to the same rule-2/rule-3 judgement at the whole-file level only if the file was never customized.
   • bun.lock: never copied — regenerate with bun install after the reconcile.
   • .env*, deploy_key.pem: never touched.

Targeted edits for the shell rollout

The performance/accessibility pass on template main (prerendered chrome, optimizer-served favicon, AA colour tokens) is mostly self-propagating, but two paths need help:

• New files land on their own under rule 4 — scripts/check-shell.sh, scripts/audit.sh, lib/contrast.ts, lib/contrast.test.ts, app/palette.test.ts, lint-staged.config.mjs. Nothing to do.

• package.json scripts.build must be ported even when the file counts as customized, because the build gate is the whole point of the change:

  jq '.scripts.build = "bun next build && bash scripts/check-shell.sh"' package.json | sponge package.json
  

  Add .scripts.audit = "bash scripts/audit.sh" the same way. Everything else in scripts stays as the store has it.

• app/layout.tsx is ~52 commits of churn on main and will almost always come back as skipped (customized). Do not merge it. Put it in the "needs manual follow-up" list with these three targeted edits spelled out, so a follow-up run (or a human) can apply them:

  1. remove the <Suspense> around the children/chrome wrapper if everything it awaits is a cached read — the boundary alone streams the chrome out of the prerendered shell; a store that still awaits its cart cookie there must move that read into a CartBootstrapper below the chrome first;
  2. replace the icons block in the metadata with the optimizer version — one icon entry built with getImageProps and no type, apple left on the original URL, no shortcut;
  3. Geist_Mono({ …, preload: false }).

  After such a follow-up, bun run build in the store repo is the check that says it worked.

Verify, commit, push

In each store repo, in order — a failure at any step means do not push; report instead:

1. bun install
2. bun next typegen (regenerates the route-type globals; deleted routes otherwise leave stale validators)
3. bun tsc --noEmit
4. bun run lint if the script exists (biome, auto-fix mode is fine)

Commit everything applied as one commit — subject chore: propagate template <short-sha of template main>, body listing counts (updated/deleted/skipped) and the driving issue refs if the invoker supplied them. Plain push to main, never force. Remember each push redeploys that tenant — when running across a fleet, process a handful at a time rather than pushing dozens simultaneously.

Scale + report

One store = one agent task; run a few in parallel, each in its own temp dir. At the end, produce a single table: store · updated · deleted · skipped(customized) · pushed?/error. Anything skipped (customized) for a file the invoker's change actually needs (e.g. an edit inside a customized app/layout.tsx) belongs in a "needs manual follow-up" list with the store name and path — do not attempt semantic merges of customized files unless the invoker explicitly described the targeted edit to make (e.g. "remove the AuthButton import and its render line if present").

Live spot-check (optional, when the invoker names expectations)

After a store's push + redeploy, curl -sI https://<subdomain>.<yns.cx|yns.store><path> against whatever the propagated change promises (e.g. a proxied path now answering with a platform redirect instead of the template 404). Remember tenant 404s stream with HTTP 200 — check content or headers, not just the status code.