gitignore — seed .gitignore (E10)

Status: shipped-beta · Ships to: npm-lane, all tier arms (core / env+ / factory) · Fires at: install time (setup.d/40-configs.sh shared-templates block)

What it is

A deliberately undotted template file named gitignore whose five lines are the minimal ignore set a fresh consumer needs: node_modules/, dist/, coverage/, .stryker-tmp/, reports/. The installer copies it to the consumer's project root as .gitignore.

How it works

• The source file is NOT dotted on purpose: the npm tarball packaging drops dotted files from its manifest (measured in-stage and commented at the delivery site), so a dotted source would silently vanish on the npm delivery channel and copy_safe would fail.
• Without a seed, a gitignore-less consumer staging git add -A would commit node_modules/ — and lint-staged's per-directory config discovery would then execute vendored configs from inside node_modules. The seed exists to close exactly that hole.
• copy_safe semantics apply in full: an existing consumer .gitignore is recorded SKIPPED and left untouched — Layer-2 ownership, warned below, never edited.
• The stage adds one honesty guard after delivery: if the (kept) consumer .gitignore has no node_modules line, the install prints a warning saying git add -A will stage node_modules and suggesting the line — the file stays untouched either way.
• Lane honesty: npm-lane only — the python, cargo and go lanes deliver no .gitignore seed (their stages have no gitignore reference).

Satellites & companions

Delivered by the same 40-configs stage (A13) as its neighbors .lintstagedrc.json (E1) and .prettierignore (E3); the same _prettierignore_in_skipped helper that classifies the prettierignore classifies this file's skip state. The pre-commit chain (E12 / D20) is the downstream consumer of the guarantee it seeds.

Anchors

At framework pin aa87d0a47a6d8502f983cc9fe7284bd5dcb3d650:

• packages/core/templates/shared/gitignore:1 — «node_modules/»
• packages/core/templates/shared/gitignore:4 — «.stryker-tmp/»
• setup.d/40-configs.sh:105 — «copy_safe "$PKG_ROOT/packages/core/templates/shared/gitignore" "$PROJECT_ROOT/.gitignore"»
• setup.d/40-configs.sh:100-104 — «# drops a dotted .gitignore from the tarball (measured 2026-09-02), so a dotted source would be» … «# .gitignore always wins (Layer-2) — warned below, never edited.»
• setup.d/40-configs.sh:107 — «echo " ⚠ .gitignore exists without a node_modules line — 'git add -A' will stage node_modules/. Consider adding node_modules/ to .gitignore (file left untouched)." >&2»