diff --git a/CHANGELOG.md b/CHANGELOG.md
new file mode 100644
index 0000000..c9ac0f0
--- /dev/null
+++ b/CHANGELOG.md
@@ -0,0 +1,79 @@
+# Changelog
+
+All notable changes to this documentation repository, grouped by version and release date.
+Document versions of the individual guideline files are tracked separately in their headers.
+
+## 0.4.0 — 2026-08-18
+
+### Added
+- Skill versioning: every `SKILL.md` now carries `metadata.version` — `changelog` v2, `check` v1,
+  `commit` v2, `documentation` v1, `documentation_context` v2. The skill format has no top-level
+  `version` field; `metadata` is one of the six Agent Skills spec fields, so the frontmatter still
+  packages and uploads cleanly
+- "Skills" section in `README.md` describing the versioning convention, the install location
+  (`~/.claude/skills/`) and the rule that the folder name — not `name:` — is the command
+- The five skills listed individually in the `README.md` structure tree
+- `AGENTS.md` v5 → v6: new "Commit messages" subsection under Git — commits and pull requests must
+  never carry AI authorship (`Co-Authored-By`, "Generated with …", tool signatures or emoji footers).
+  The subsection also states the single-line verbal English style, so assistants without the `commit`
+  skill get the same rules; the AI-authorship rule was added to the skill as well
+- `CHANGELOG.md` for this repository, with history backfilled from the git log
+- Explicit line length for Rust: 100 characters (rustfmt default `max_width`) in both Rust design documents
+- `README.md`, `docs/`, `prebuild.py` and the PyInstaller `.spec` to the template structure in `Python/TEMPLATE.md`
+- Note in `Python/TEMPLATE.md` that `AGENTS.md` and `DESIGN_DOCUMENT.md` are not part of the template
+- `README.md` to the session read list in `Claude/CLAUDE.md`, plus a missing top-level heading
+
+### Changed
+- Document versions bumped for the structural changes released on 2026-08-18:
+  `DESIGN_DOCUMENT.md` v8 → v9, `DESIGN_DOCUMENT_MODULE.md` v1 → v2,
+  `Rust/DESIGN_DOCUMENT.md` v1 → v2, `Rust/DESIGN_DOCUMENT_LIB.md` v1 → v2,
+  `DESIGN_DOCUMENT_GODOT.md` v1 → v2
+- `Project template/CHANGELOG.md` now names the project manifest generically
+  (`pyproject.toml`, `Cargo.toml`, `project.godot`) instead of `pyproject.toml` only
+- Godot debug constant renamed `Constants.DEBUG` → `Constants.DEFAULT_DEBUG`, matching the Python reference module
+- `README.md` step 1 of "Starting a new project" now also requires writing a `README.md`
+- `Python/TEMPLATE.md` entry point is named by purpose or tool name instead of `main.py`
+- `prebuild.py` loads `.env` before importing `src.constants` instead of relying on the import side effect
+
+### Fixed
+- Skill folder `Claude/skills/context/` renamed to `documentation_context/`, with the frontmatter
+  `name` matched to it. The folder name is what Claude Code turns into the command, so the old
+  mismatch meant installing from this repository would have changed `/documentation_context`
+  into `/context`
+- Removed the misplaced lock-file rule from the Testing sections of `DESIGN_DOCUMENT_MODULE.md` (§9)
+  and `Rust/DESIGN_DOCUMENT_LIB.md` (§8) — it already belongs to the Poetry / Distribution sections
+
+## 0.3.0 — 2026-08-18
+
+### Added
+- `Zscaler/ZSCALER_CERTIFICATE.md` — full certificate setup for Node, Python, git and cargo
+- Language-specific `.gitignore` files for Python, Rust and Godot, plus a shared core in `Project template/`
+- `poetry.lock` and `prebuild.py` sections in `Python/DESIGN_DOCUMENT.md`
+
+### Changed
+- Unified task notation across all languages on the Todo Tree tags `TODO`, `FIXME`, `BUG`, `HACK`, `NOTE`
+- `AGENTS.md` v4 → v5: rewritten as strictly language-agnostic, naming no concrete tool
+- Python line length 150 → 120 characters
+- Rust edition 2021 → 2024 (requires Rust 1.85 or newer)
+- Godot project version key corrected to `application/config/version`
+- Every design document now lists `README.md` among the core root documents
+
+### Removed
+- `Zscaler/NODE_EXTRA_CA_CERTS.md`, superseded by `ZSCALER_CERTIFICATE.md`
+
+## 0.2.0 — 2026-06-24
+
+### Added
+- `Godot/DESIGN_DOCUMENT_GODOT.md` — Godot development guidelines (v1)
+
+## 0.1.0 — 2026-05-25
+
+### Added
+- `Rust/DESIGN_DOCUMENT.md` and `Rust/DESIGN_DOCUMENT_LIB.md` — Rust guidelines for applications and libraries (v1)
+- `Claude/` — `CLAUDE.md`, `AGENTS.md` (v4) and the custom skills `changelog`, `check`, `commit`, `context`, `documentation`
+- `Python/` — `DESIGN_DOCUMENT.md` (v8), `DESIGN_DOCUMENT_MODULE.md` (v1), `TEMPLATE.md`, and the reference `constants.py` module with tests
+- `Project template/` — `PROJECT.md` and `CHANGELOG.md` templates
+
+### Changed
+- Documentation organised into topic folders: `Claude/`, `Python/`, `Zscaler/`, `Project template/`
+- `README.md` rewritten to describe the repository itself instead of a single project
diff --git a/Claude/AGENTS.md b/Claude/AGENTS.md
index 7d940a0..053c8a8 100644
--- a/Claude/AGENTS.md
+++ b/Claude/AGENTS.md
@@ -1,6 +1,6 @@
 # AI Agents - Project Rules
 
-**Document Version:** v5 (independent, incremented on structural changes)
+**Document Version:** v6 (independent, incremented on structural changes)
 
 Language-agnostic rules for AI assistants (Claude Code, Cursor, Copilot, etc.).
 
@@ -68,6 +68,13 @@ Where this file and a design document disagree, **the design document wins**.
 - **Never commit shared documentation** (`AGENTS.md`, `DESIGN_DOCUMENT*.md`) — it comes from the documentation repository, not from the project
 - `README.md`, `PROJECT.md` and `CHANGELOG.md` **are committed** — they are project-specific
 
+### Commit messages
+
+- **Never sign commits with AI authorship** — no `Co-Authored-By: Claude` (or any other assistant), no "Generated with …" line, no tool name or emoji footer. The same applies to pull request descriptions and issue comments.
+- The commit author is the human running the tool; the message describes the change, nothing else
+- Single-line verbal style — "Add X", "Fix Y", "Refactor Z" — never a filename-style message
+- Written in English
+
 ## Versioning
 
 - Follow semantic versioning (MAJOR.MINOR.PATCH)
diff --git a/Claude/CLAUDE.md b/Claude/CLAUDE.md
index 303b099..1972560 100644
--- a/Claude/CLAUDE.md
+++ b/Claude/CLAUDE.md
@@ -1,10 +1,12 @@
+# CLAUDE.md
 
 ## First-time setup
 
 **At the start of every new session, read all of the following files before doing anything else:**
 
 - `CLAUDE.md` (this file)
+- `README.md`
 - `AGENTS.md`
 - `PROJECT.md`
 - `CHANGELOG.md`
-- `DESIGN_DOCUMENT*.md` (`DESIGN_DOCUMENT.md`, `DESIGN_DOCUMENT_MODULE.md`, `DESIGN_DOCUMENT_LIB.md` or `DESIGN_DOCUMENT_GODOT.md`)
\ No newline at end of file
+- `DESIGN_DOCUMENT*.md` (`DESIGN_DOCUMENT.md`, `DESIGN_DOCUMENT_MODULE.md`, `DESIGN_DOCUMENT_LIB.md` or `DESIGN_DOCUMENT_GODOT.md`)
diff --git a/Claude/skills/changelog/SKILL.md b/Claude/skills/changelog/SKILL.md
index 2eef8aa..b80c1b3 100644
--- a/Claude/skills/changelog/SKILL.md
+++ b/Claude/skills/changelog/SKILL.md
@@ -1,6 +1,8 @@
 ---
 name: changelog
 description: Updates changelog in project
+metadata:
+  version: v2
 ---
 
 Take known info and make changes to CHANGELOG.md to make them up-to-date.
diff --git a/Claude/skills/check/SKILL.md b/Claude/skills/check/SKILL.md
index db1395f..a273102 100644
--- a/Claude/skills/check/SKILL.md
+++ b/Claude/skills/check/SKILL.md
@@ -1,5 +1,7 @@
 ---
 name: check
 description: Check for failed tests
+metadata:
+  version: v1
 ---
 Try running tests and investigate failed results
\ No newline at end of file
diff --git a/Claude/skills/commit/SKILL.md b/Claude/skills/commit/SKILL.md
index 9f5fa14..943735d 100644
--- a/Claude/skills/commit/SKILL.md
+++ b/Claude/skills/commit/SKILL.md
@@ -1,6 +1,8 @@
 ---
 name: commit
 description: Updates changelog and proposes a concise verbal git commit message
+metadata:
+  version: v2
 ---
 
 1. Run the changelog skill: read git log and staged changes, then update CHANGELOG.md accordingly (same as /changelog).
@@ -9,4 +11,5 @@ description: Updates changelog and proposes a concise verbal git commit message
    - Concise, verbal style — e.g. "Add X", "Fix Y", "Refactor Z"
    - NOT filename-style — never "update_something.py" or "changes to foo"
    - In English
+   - **No AI authorship** — never append `Co-Authored-By: Claude`, a "Generated with …" line, or any tool signature or emoji footer. The same applies to pull request descriptions.
    - Do NOT run git commit — only propose the message and wait for user confirmation.
diff --git a/Claude/skills/documentation/SKILL.md b/Claude/skills/documentation/SKILL.md
index 6818979..81a54cf 100644
--- a/Claude/skills/documentation/SKILL.md
+++ b/Claude/skills/documentation/SKILL.md
@@ -1,5 +1,7 @@
 ---
 name: documentation
 description: Updates documentation in project
+metadata:
+  version: v1
 ---
 Create or update documentation of project in docs/ folder. Documentation should contain description of each part of program and documentation of each function. Separate documents for each module. Write in markdown format.
\ No newline at end of file
diff --git a/Claude/skills/context/SKILL.md b/Claude/skills/documentation_context/SKILL.md
similarity index 96%
rename from Claude/skills/context/SKILL.md
rename to Claude/skills/documentation_context/SKILL.md
index 980ec44..538e681 100644
--- a/Claude/skills/context/SKILL.md
+++ b/Claude/skills/documentation_context/SKILL.md
@@ -1,6 +1,8 @@
 ---
-name: context
+name: documentation_context
 description: Compress docs/ into CONTEXT.md at project root — minimum tokens, lossless
+metadata:
+  version: v2
 ---
 
 Read every `.md` file in `docs/`. Generate `CONTEXT.md` at the project root.
diff --git a/Godot/DESIGN_DOCUMENT_GODOT.md b/Godot/DESIGN_DOCUMENT_GODOT.md
index c716df7..f9005a5 100644
--- a/Godot/DESIGN_DOCUMENT_GODOT.md
+++ b/Godot/DESIGN_DOCUMENT_GODOT.md
@@ -1,6 +1,6 @@
 # Godot Development Guidelines
 
-**Document Version:** v1
+**Document Version:** v2
 
 > **Note on Versioning:**
 > - This document version is independent — reused across Godot projects
@@ -90,7 +90,7 @@ Use a dedicated `Log` autoload that wraps `print`/`push_warning`/`push_error` wi
 
 The file sink retains **max 10 log files**. Each run creates a new file via the timestamp in the filename.
 
-The `DEBUG` sink is only active when `Constants.DEBUG` is `true` (controlled by an `ENV_DEBUG` value read at startup, e.g. from a `user://settings.cfg` or an export feature tag).
+The `DEBUG` sink is only active when `Constants.DEFAULT_DEBUG` is `true` (controlled by an `ENV_DEBUG` value read at startup, e.g. from a `user://settings.cfg` or an export feature tag).
 
 Additional sinks (e.g. an in-game debug overlay / console panel) may be added per project.
 
@@ -112,7 +112,7 @@ Additional sinks (e.g. an in-game debug overlay / console panel) may be added pe
 ## 7. Settings and Secrets
 
 - Store user/runtime config in `user://settings.cfg` via `ConfigFile`
-- Toggle debug behaviour with an `ENV_DEBUG`-style flag read at startup into `Constants.DEBUG`
+- Toggle debug behaviour with an `ENV_DEBUG`-style flag read at startup into `Constants.DEFAULT_DEBUG`
 - Never commit any secrets; keep them out of `project.godot` and committed `.tres`/`.cfg` files
 
 ---
@@ -191,7 +191,7 @@ When the game is distributed as a standalone build:
   godot --headless --export-release "Windows Desktop" build/Game.exe
   ```
 - Compiled builds are stored in `build/` (or `dist/`). Decide per project whether builds are committed — for small internal distribution the repository may serve as the channel; otherwise keep `build/` in `.gitignore`
-- Strip debug-only nodes and disable `Constants.DEBUG` in release presets
+- Strip debug-only nodes and disable `Constants.DEFAULT_DEBUG` in release presets
 
 > This section applies only to projects that produce shippable builds.
 
diff --git a/Project template/CHANGELOG.md b/Project template/CHANGELOG.md
index 7cb4fc0..6b2ac05 100644
--- a/Project template/CHANGELOG.md	
+++ b/Project template/CHANGELOG.md	
@@ -16,5 +16,5 @@ Each version entry uses these sections (include only those that apply):
 
 - Follow semantic versioning: `MAJOR.MINOR.PATCH`
 - Newest version goes at the top
-- Always update this file before bumping the version in `pyproject.toml`
+- Always update this file before bumping the version in the project manifest (`pyproject.toml`, `Cargo.toml`, `project.godot`)
 - Document changes as they are made, not all at once at release time
diff --git a/Python/DESIGN_DOCUMENT.md b/Python/DESIGN_DOCUMENT.md
index 604af96..693aeba 100644
--- a/Python/DESIGN_DOCUMENT.md
+++ b/Python/DESIGN_DOCUMENT.md
@@ -1,6 +1,6 @@
 # Python Development Guidelines
 
-**Document Version:** v8
+**Document Version:** v9
 
 > **Note on Versioning:**
 > - This document version is independent — reused across projects
diff --git a/Python/DESIGN_DOCUMENT_MODULE.md b/Python/DESIGN_DOCUMENT_MODULE.md
index 1906942..4fcfa84 100644
--- a/Python/DESIGN_DOCUMENT_MODULE.md
+++ b/Python/DESIGN_DOCUMENT_MODULE.md
@@ -1,6 +1,6 @@
 # Python Library Development Guidelines
 
-**Document Version:** v1
+**Document Version:** v2
 
 > **Note on Versioning:**
 > - This document version is independent — reused across projects
@@ -127,7 +127,6 @@ Define specific exception types in `src/<package>/exceptions.py`. Use a fail-fas
 - **pytest** only — no `unittest`, no `TestCase` classes, no `self.assert*`
 - Arrange-Act-Assert pattern
 - Test naming: `test_<action>_<context>`
-- Do not commit `poetry.lock` — this is a library; consumers pin their own dependencies
 
 ---
 
diff --git a/Python/TEMPLATE.md b/Python/TEMPLATE.md
index 57c91a7..f3568f1 100644
--- a/Python/TEMPLATE.md
+++ b/Python/TEMPLATE.md
@@ -8,12 +8,15 @@ Create a `template/` folder in project root with reusable files for new Python p
 template/
 ├── .env                    # Environment variables (sample)
 ├── .gitignore              # Git ignore rules
-├── AGENTS.md               # AI assistant rules
 ├── CHANGELOG.md            # Changelog template
-├── DESIGN_DOCUMENT.md      # Development guidelines
 ├── PROJECT.md              # Project documentation template
-├── main.py                 # Entry point with loguru
+├── README.md               # Project overview, tool descriptions, build instructions
+├── <tool_name>.py          # Entry point — named by purpose or tool name
+├── <tool_name>.spec        # PyInstaller spec (only for projects shipping an .exe)
+├── prebuild.py             # Pre-build script: venv check, version print, console= rewrite
 ├── pyproject.toml          # Poetry config (ruff, mypy, pytest)
+├── docs/
+│   └── .gitkeep            # Detailed documentation lives here, never in the root
 ├── src/
 │   ├── __init__.py
 │   ├── _version.py         # Version fallback for PyInstaller
@@ -23,12 +26,16 @@ template/
     └── test_constants.py   # Basic test
 ```
 
+`AGENTS.md` and `DESIGN_DOCUMENT.md` are **not** part of the template — they are copied
+into the project root from the documentation repository and are never committed.
+
 ## Key Features
 
 - **Version extraction** from `pyproject.toml` with `_version.py` fallback for PyInstaller builds
 - **DEBUG mode** via `ENV_DEBUG=true` in `.env` (adds "DEV" suffix to version: v1.2.3DEV)
-- **loguru** for logging (never print)
-- **Poetry** for dependency management
+- **Build configuration** via `ENV_BUILD_CONSOLE` and `ENV_BUILD_SPEC` in `.env`, applied by `prebuild.py`
+- **loguru** for logging (never print for debugging)
+- **Poetry** for dependency management, `poetry.lock` committed
 - **pytest** for testing (no unittest)
 - **ruff + mypy** for linting and type checking (120-character lines)
 
@@ -38,3 +45,5 @@ template/
 - Generic/reusable format
 - Keep files simple and minimal
 - `.gitignore` is the shared core from `Project template/.gitignore` with `Python/.gitignore` appended
+- Entry point is named by purpose or tool name — a project may have several
+- `prebuild.py` and the `.spec` file are only needed for projects distributed as a standalone `.exe`
diff --git a/Python/prebuild.py b/Python/prebuild.py
index 7d400b4..83f61e9 100644
--- a/Python/prebuild.py
+++ b/Python/prebuild.py
@@ -4,10 +4,12 @@ from pathlib import Path
 
 from dotenv import load_dotenv
 
-from src.constants import VERSION
-
+# .env must be loaded before src.constants is imported — constants.py reads ENV_DEBUG
+# at import time to build VERSION.
 load_dotenv()
 
+from src.constants import VERSION  # noqa: E402
+
 print("=" * 50)
 print("PREBUILD CONFIGURATION")
 print("=" * 50)
diff --git a/README.md b/README.md
index 3a3f41f..7077d01 100644
--- a/README.md
+++ b/README.md
@@ -14,6 +14,11 @@ Dokumentace/
 │   ├── CLAUDE.md                    # Claude Code session instructions
 │   ├── AGENTS.md                    # Language-agnostic rules for all AI assistants
 │   └── skills/                      # Custom Claude Code skills
+│       ├── changelog/               #   /changelog — update CHANGELOG.md
+│       ├── check/                   #   /check — run tests, investigate failures
+│       ├── commit/                  #   /commit — changelog + commit message proposal
+│       ├── documentation/           #   /documentation — write docs/
+│       └── documentation_context/   #   /documentation_context — compress docs/ into CONTEXT.md
 │
 ├── Python/                          # Python development guidelines
 │   ├── DESIGN_DOCUMENT.md           # Guidelines for Python applications
@@ -38,9 +43,11 @@ Dokumentace/
 │   ├── PROJECT.md                   # Project documentation template
 │   └── .gitignore                   # Shared, language-agnostic ignore rules
 │
-└── Zscaler/                         # Corporate network setup
-    ├── ZSCALER_CERTIFICATE.md       # Cert setup for Node, Python, git, cargo
-    └── ZscalerRootCertificate-2048-SHA256.crt
+├── Zscaler/                         # Corporate network setup
+│   ├── ZSCALER_CERTIFICATE.md       # Cert setup for Node, Python, git, cargo
+│   └── ZscalerRootCertificate-2048-SHA256.crt
+│
+└── CHANGELOG.md                     # History of this repository
 ```
 
 ## AI Coding Workflow
@@ -62,11 +69,38 @@ Where the two disagree, **the design document wins**.
 
 ### Starting a new project
 
-1. Copy `Project template/PROJECT.md` and `Project template/CHANGELOG.md` into the project root — both are committed.
+1. Copy `Project template/PROJECT.md` and `Project template/CHANGELOG.md` into the project root and write a `README.md` — all three are committed.
 2. Build `.gitignore` from `Project template/.gitignore` plus the `.gitignore` of the matching language folder.
 3. Copy `Claude/AGENTS.md` and the matching `DESIGN_DOCUMENT*.md` into the project root — these are **not** committed, they come from here.
 4. For Python, follow `Python/TEMPLATE.md` to generate the project skeleton.
 
+### Skills
+
+The skills in `Claude/skills/` are the source of truth; the copies Claude Code actually runs live in
+`~/.claude/skills/`. Install or refresh them by copying the whole folder across.
+
+Two rules keep the two sides from drifting apart:
+
+- **The folder name is the command.** For personal skills the frontmatter `name` is only a display
+  label — `/documentation_context` comes from the directory, not from `name:`. Keep the two identical
+  so renaming a folder can never silently change the command.
+- **Every skill carries a version** in `metadata.version`, incremented on every content change, the
+  same way design documents carry `Document Version`:
+
+  ```yaml
+  ---
+  name: commit
+  description: Updates changelog and proposes a concise verbal git commit message
+  metadata:
+    version: v2
+  ---
+  ```
+
+  There is no top-level `version:` field in the skill format. `metadata` is a free-form map that
+  Claude Code ignores, and it is one of the six fields the [Agent Skills](https://agentskills.io)
+  spec allows — so it also survives an upload to claude.ai or the Skills API. Any other invented
+  key fails packaging with `Unexpected key(s) in SKILL.md frontmatter`.
+
 ## Key Conventions
 
 - **Python tooling:** Poetry · Ruff · mypy · pytest · loguru
@@ -74,7 +108,7 @@ Where the two disagree, **the design document wins**.
 - **Godot tooling:** gdformat · gdlint · GUT
 - **No `print()` for debugging** — the language's logging library, everywhere
 - **Static typing required** on every parameter and return value
-- **Line length:** 120 characters (Python), 100 soft limit (GDScript)
+- **Line length:** 120 characters (Python), 100 characters (Rust, rustfmt default), 100 soft limit (GDScript)
 - **Tests:** the framework named in the design document — pytest (Python, never `unittest`), built-in `#[test]` (Rust), GUT (Godot)
 - **Tasks:** single-line `TODO` / `FIXME` / `BUG` / `HACK` / `NOTE` comments in code — no checkboxes in documentation
 - **Versioning:** semantic, always ask before bumping, `CHANGELOG.md` updated first
diff --git a/Rust/DESIGN_DOCUMENT.md b/Rust/DESIGN_DOCUMENT.md
index d2f1176..551f12d 100644
--- a/Rust/DESIGN_DOCUMENT.md
+++ b/Rust/DESIGN_DOCUMENT.md
@@ -1,6 +1,6 @@
 # Rust Application Development Guidelines
 
-**Document Version:** v1
+**Document Version:** v2
 
 > **Note on Versioning:**
 > - This document version is independent — reused across projects
@@ -25,6 +25,7 @@ The root directory contains only the core documents: `README.md`, `AGENTS.md`, `
 ## 1. Code Style
 
 - **Rust edition:** 2024 (requires Rust 1.85 or newer)
+- **100-character lines** (rustfmt default `max_width`)
 - Format with **rustfmt** — run `cargo fmt` before every commit
 - Lint with **clippy** — run `cargo clippy -- -D warnings` before every commit
 - **snake_case** functions/variables/modules, **PascalCase** types/traits, **SCREAMING_SNAKE_CASE** constants
diff --git a/Rust/DESIGN_DOCUMENT_LIB.md b/Rust/DESIGN_DOCUMENT_LIB.md
index 868b513..d1d7322 100644
--- a/Rust/DESIGN_DOCUMENT_LIB.md
+++ b/Rust/DESIGN_DOCUMENT_LIB.md
@@ -1,6 +1,6 @@
 # Rust Library Development Guidelines
 
-**Document Version:** v1
+**Document Version:** v2
 
 > **Note on Versioning:**
 > - This document version is independent — reused across projects
@@ -28,6 +28,7 @@ The root directory contains only the core documents: `README.md`, `AGENTS.md`, `
 
 - **Rust edition:** 2024 (requires Rust 1.85 or newer)
 - Declare the minimum toolchain in `Cargo.toml` (`rust-version = "1.85"`) so consumers get a clear error instead of a compile failure
+- **100-character lines** (rustfmt default `max_width`)
 - Format with **rustfmt** — run `cargo fmt` before every commit
 - Lint with **clippy** — run `cargo clippy -- -D warnings` before every commit
 - **snake_case** functions/variables/modules, **PascalCase** types/traits, **SCREAMING_SNAKE_CASE** constants
@@ -169,8 +170,6 @@ mod tests {
 }
 ```
 
-`Cargo.lock` is **not committed** for libraries — add it to `.gitignore`. Consumers pin their own dependency graph.
-
 ---
 
 ## 9. Documentation