Conventional Commits CLI — zero dependencies, 1300 lines of bash.

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Install

npm (any project — no Node required at runtime)

npm install -g @mihairo/cmt

Homebrew

brew tap mihairo/tap
brew install cmt

curl (no package manager)

curl -fsSL https://raw.githubusercontent.com/mihai-ro/cmt/main/cmt \
  -o ~/.local/bin/cmt && chmod +x ~/.local/bin/cmt

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Usage

cmt <command> [flags]

  init [--husky] [--lint]   create .cmt.json + install git hook(s)
  commit                     interactive commit builder
  lint [file]                lint a message file or stdin  →  exit 1 on error
  log [n]                    pretty log of last n commits  (default: 20)
  types                      list available commit types
  uninstall                  remove cmt-managed hooks and .cmt.json
  version

Set up a repo:

cd my-project
cmt init                 # picker hook only
cmt init --lint          # picker + lint git commit -m "..." commits
cmt init --husky         # husky v9 format  (.husky/prepare-commit-msg)
cmt init --husky --lint  # both hooks, husky format

Guided interactive commit:

git add .
git commit     # triggers the interactive picker automatically
# or:
cmt commit     # run directly

Lint from anywhere:

echo "feat(api): add login" | cmt lint          # exit 0
echo "bad message"          | cmt lint          # exit 1

# lint every commit on a branch (CI)
git log --format="%s" origin/main..HEAD | while IFS= read -r msg; do
  echo "$msg" | cmt lint || exit 1
done

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Commit format

<type>[optional scope]: <description>

[optional body]

[optional footer(s)]

Breaking change:

feat!: drop support for Node 14
feat(api)!: redesign endpoints
BREAKING CHANGE: /auth now returns JWT

Built-in types

Type	Emoji	SemVer impact
feat	✨	minor
fix	🐛	patch
docs	📚	—
style	💅	—
refactor	♻️	—
perf	⚡	patch
test	🧪	—
build	🏗️	—
ci	🔧	—
chore	🔩	—
revert	⏪	patch

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Configuration — .cmt.json

cmt init creates .cmt.json at your repo root with a $schema pointer. VS Code, JetBrains, and any JSON Language Server will autocomplete and validate it automatically — no extension needed.

{
  "$schema": "https://raw.githubusercontent.com/mihai-ro/cmt/main/schema/cmt.schema.json",
  "customTypes": [
    {
      "type": "wip",
      "emoji": "🚧",
      "semver": "none",
      "description": "Work in progress"
    },
    {
      "type": "security",
      "emoji": "🔒",
      "semver": "patch",
      "description": "Security fix"
    }
  ],
  "scopes": ["auth", "api", "ui", "db"],
  "rules": {
    "maxHeaderLength": 72,
    "requireScope": false,
    "allowBreakingChanges": ["feat", "fix"],
    "disallowUpperCaseDescription": false,
    "disallowTrailingPeriod": false
  }
}

Scopes — when the scopes array is non-empty, cmt commit shows an arrow-key picker with your configured scopes, a "custom" option for free-text entry, and a "skip" option. Leave scopes empty to always use free-text input.

Commit .cmt.json — your whole team shares the same types, scopes, and rules.

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Hooks

prepare-commit-msg (always installed)

Intercepts plain git commit, runs the interactive picker, and writes the message — so git never opens its editor. Skips amends, merges, squashes, and any commit that already has a source message.

commit-msg (opt-in via --lint)

Lints the final commit message. Catches git commit -m "...", --amend, and commits from GUI tools:

cmt init --lint

Both hooks follow the same append/create pattern — if a hook file already exists they append a clearly-marked block rather than overwriting it. cmt uninstall removes only the cmt blocks, leaving any other content intact.

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Integrations

Husky v9

cmt init --husky --lint    # writes .husky/prepare-commit-msg + .husky/commit-msg
git add .husky/            # commit them — every teammate gets them on clone

lint-staged

Add to .husky/pre-commit:

npx lint-staged

cmt handles commit message linting separately — the two hooks are completely independent.

GitHub Actions

- name: Lint commit messages
  run: |
    git log --format="%s" origin/main..HEAD | while IFS= read -r msg; do
      echo "$msg" | cmt lint || exit 1
    done

Git operations and hook behaviour

Operation	Hook fires?	Result
git commit	✅	picker runs
git commit -m "..."	✅ with --lint	linted
git commit --amend	✅ with --lint	linted
git merge --no-ff	✅	⏭ skipped (auto-generated message)
git revert	✅	⏭ skipped (auto-generated message)
fixup! / squash!	✅	⏭ skipped
git pull --rebase	✅	✅ passes (replays existing commits)
Empty/aborted commit	✅	⏭ skipped

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Lint rules

Rule	Config key	Default	On fail
Header format type(scope)?: description	—	required	❌ error
Valid type	—	required	❌ error
Non-empty description	—	required	❌ error
Blank line before body	—	required	❌ error
Scope required	requireScope	false	❌ error
Uppercase description	disallowUpperCaseDescription	false	⚠️ / ❌
Trailing period	disallowTrailingPeriod	false	⚠️ / ❌
Header length	maxHeaderLength	72	⚠️ warning

Warnings exit 0. Errors exit 1.

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Why not commitlint + husky + commitizen?

	cmt	commitlint + husky	commitizen
Runtime dependencies	0	~15 npm packages	Python + pip
Works in any language repo	✅	❌ needs Node	❌ needs Python
Install	copy one file	npm install	pip install
Interactive commit prompt	✅	via cz-commitlint	✅
Commit-msg linting	✅ opt-in --lint	✅	✅
Husky v9 support	✅	native	via config
JSON Schema / intellisense	✅	partial	❌
Custom types + scopes	✅ .cmt.json	✅	✅

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License

MIT