Say where a repository's own .gitignore and .editorconfig entries go (closes #103)

The canonical `.gitignore` had no place for a repository's own build outputs, and nothing said a repository's own `.editorconfig` sections survive a re-vendor, so re-vendoring dropped them: a Go repository lost `/bin/`, `*.test` and `*.out`, and its tabs for Go files.

`.gitignore` now ends with a section, like `.dockerignore`'s header, where a repository adds its own build outputs (a root binary written `/myapp`) and its own environment-template negations, which a re-vendor keeps. `.editorconfig` gains `[*.go]` with tabs and the same kind of closing note. `prompts/REPO_POLICIES.md`, both checklists and the Go styleguide say these two files are the canonical content followed by the repository's own entries. Closes #104 too.

Model: opus-5-5

.editorconfig

@@ -10,3 +10,9 @@ insert_final_newline = true
 
 [Makefile]
 indent_style = tab
+
+[*.go]
+indent_style = tab
+
+# This repository's own sections, such as one for another language it
+# uses, go below this comment, and a re-vendor keeps them.

.gitignore

@@ -27,7 +27,7 @@ node_modules/
 # Environment files. `*.env` covers bare `.env` and the `prod.env`
 # convention. Only the templates `example.env` and `sample.env` are
 # re-included below. A repository that commits any other template adds
-# its own negation after these lines, for example `!.env.example`.
+# its own negation at the end of this file, for example `!.env.example`.
 *.[eE][nN][vV]
 .[eE][nN][vV].*
 .[eE][nN][vV][rR][cC]
@@ -45,3 +45,7 @@ node_modules/
 [iI][dD]_[eE][cC][dD][sS][aA]_[sS][kK]
 [iI][dD]_[eE][dD]25519
 [iI][dD]_[eE][dD]25519_[sS][kK]
+
+# This repository's own entries, such as its build outputs, go below
+# this comment, and a re-vendor keeps them. Anchor a binary built at the
+# root: `/myapp`, never `myapp`, which also ignores `cmd/myapp/`.

TODO.md

@@ -21,6 +21,15 @@ fmt-check, and commit.
 
 # Completed Steps
 
+- 2026-10-06: The canonical `.gitignore` and `.editorconfig` now each end with a
+  comment saying the repository's own entries go below it and a re-vendor keeps
+  them (issue 103, which took in issue 104), as `.dockerignore`'s header already
+  does. `.editorconfig` gains a `[*.go]` section with tabs, since `gofmt`
+  decides Go indentation everywhere. `REPO_POLICIES.md` and both checklists say
+  that each of these two files is the canonical content followed by the
+  repository's own entries, which a re-vendor keeps, and the Go styleguide puts
+  `*.log`, `*.out`, `*.test` and binaries among those entries. Common outputs
+  stay out of the canonical `.gitignore`; each repository lists its own.
 - 2026-10-05: `script/cibuild`, `script/docker`, `script/lint` and `script/test`
   now assign the image tag from `script/projectname` on its own line before the
   `docker build` (issue 101), so `set -e` stops the script where

prompts/CODE_STYLEGUIDE_GO.md

@@ -1,6 +1,6 @@
 ---
 title: Code Styleguide — Go
-last_modified: 2026-10-04
+last_modified: 2026-10-06
 ---
 
 1.  Try to hard wrap long lines at 77 characters or less.
@@ -148,8 +148,9 @@ last_modified: 2026-10-04
     handle HTTP requests. Don't use methods or your top level functions as
     handlers.
 
-1.  Provide a .gitignore file that ignores at least `*.log`, `*.out`, and
-    `*.test` files, as well as any binaries.
+1.  The repository's own entries at the end of `.gitignore`, which a re-vendor
+    keeps, ignore at least `*.log`, `*.out`, and `*.test` files, as well as any
+    binaries.
 
 1.  Constructors **must** be called `New()`. `modulename.New()` works great if
     you name the packages properly. If the constructor creates an instance from

prompts/EXISTING_REPO_CHECKLIST.md

@@ -1,6 +1,6 @@
 ---
 title: Existing Repo Checklist
-last_modified: 2026-10-04
+last_modified: 2026-10-06
 ---
 
 Use this checklist when beginning work in a repo that may not yet conform to our
@@ -28,13 +28,18 @@ with your task.
       root — never a file or directory named after one agent tool, such as
       `CLAUDE.md` or `.claude/`, and never separate memory files. Move what any
       such committed file says into `AGENTS.md` and delete it.
-- [ ] `.gitignore` is comprehensive (OS, editor, agent scratch, language
-      artifacts, secrets) — fetch from
+- [ ] `.gitignore` is comprehensive (OS, editor, agent scratch, secrets, the
+      repo's own build outputs) — fetch from
       `https://git.eeqj.de/sneak/prompts/raw/branch/main/.gitignore` if missing.
       An existing repo usually has a hand-written one that is never re-fetched,
-      so check the entries rather than the file's presence.
+      so check the entries rather than the file's presence. The file is the
+      canonical content followed by the repo's own entries, such as its
+      binaries; a re-vendor replaces the canonical part and keeps those entries.
 - [ ] `.editorconfig` exists — fetch from
-      `https://git.eeqj.de/sneak/prompts/raw/branch/main/.editorconfig`
+      `https://git.eeqj.de/sneak/prompts/raw/branch/main/.editorconfig`. The
+      file is the canonical content followed by the repo's own sections, such as
+      one for another language it uses; a re-vendor replaces the canonical part
+      and keeps those sections.
 - [ ] `Dockerfile` and `.dockerignore` exist; the Dockerfile carries a `lint`
       phase and a `test` phase, and the final stage carries a `COPY --from=` of
       a harmless file from each — fetch `.dockerignore` from

prompts/NEW_REPO_CHECKLIST.md

@@ -1,6 +1,6 @@
 ---
 title: New Repo Checklist
-last_modified: 2026-10-04
+last_modified: 2026-10-06
 ---
 
 Use this checklist when creating a new repository from scratch. Follow the steps
@@ -34,14 +34,17 @@ Template files can be fetched from:
 ## Fetch Template Files
 
 - [ ] `.gitignore` — fetch from
-      `https://git.eeqj.de/sneak/prompts/raw/branch/main/.gitignore`, extend for
-      language-specific artifacts. Extensions are written to `.gitignore`'s own
-      semantics, where an unanchored pattern already matches at every depth:
-      never add a `**/` prefix here, which is a `.dockerignore` form. The
-      canonical file already carries `.claude/` so agent worktrees cannot be
-      committed by accident.
+      `https://git.eeqj.de/sneak/prompts/raw/branch/main/.gitignore`, then add
+      the repo's own build outputs, such as its binaries, at the end of the
+      file, where a re-vendor keeps them. Extensions are written to
+      `.gitignore`'s own semantics, where an unanchored pattern already matches
+      at every depth: never add a `**/` prefix here, which is a `.dockerignore`
+      form. The canonical file already carries `.claude/` so agent worktrees
+      cannot be committed by accident.
 - [ ] `.editorconfig` — fetch from
-      `https://git.eeqj.de/sneak/prompts/raw/branch/main/.editorconfig`
+      `https://git.eeqj.de/sneak/prompts/raw/branch/main/.editorconfig`, then
+      add the repo's own sections, such as one for another language it uses, at
+      the end of the file, where a re-vendor keeps them.
 - [ ] `Makefile` — fetch from
       `https://git.eeqj.de/sneak/prompts/raw/branch/main/Makefile`, adapt
       targets for the project's language and tools

prompts/REPO_POLICIES.md

@@ -1,6 +1,6 @@
 ---
 title: Repository Policies
-last_modified: 2026-10-04
+last_modified: 2026-10-06
 ---
 
 This document covers repository structure, tooling, and workflow standards. Code
@@ -387,9 +387,12 @@ style conventions are in separate documents:
 
 - `.gitignore` should be comprehensive from the start: OS files (`.DS_Store`),
   editor files (`.swp`, `*~`), in-repo agent scratch directories (`.claude/`),
-  language build artifacts, and `node_modules/`. Fetch the standard `.gitignore`
-  from `https://git.eeqj.de/sneak/prompts/raw/branch/main/.gitignore` when
-  setting up a new repo. These patterns are written to `.gitignore`'s own
+  `node_modules/`, and the repo's own build outputs. Fetch the standard
+  `.gitignore` from
+  `https://git.eeqj.de/sneak/prompts/raw/branch/main/.gitignore` when setting up
+  a new repo. A repo's `.gitignore` is the standard file followed by the repo's
+  own entries, such as its binaries; a re-vendor replaces the standard part and
+  keeps those entries. These patterns are written to `.gitignore`'s own
   semantics, in which an unanchored pattern already matches at every depth; they
   are not a `.dockerignore` and must not be transplanted into one unmodified.
 
@@ -641,7 +644,11 @@ style conventions are in separate documents:
       Never edit existing migrations after release.
 
 - All repos should have an `.editorconfig` enforcing the project's indentation
-  settings.
+  settings: the standard file from
+  `https://git.eeqj.de/sneak/prompts/raw/branch/main/.editorconfig`, which sets
+  tabs for `Makefile` and Go files, followed by the repo's own sections, such as
+  one for another language it uses. A re-vendor replaces the standard part and
+  keeps those sections.
 
 - Avoid putting files in the repo root unless necessary. Root should contain
   only project-level config files (`README.md`, `AGENTS.md`, `Makefile`,