mergelock MCP server

mergelock

A git-native merge gate. mergelock check compares two branches before they meet and reports the conflicts git itself won't tell you about: a function whose signature changed on one branch while the other branch added calls to the old signature, a symbol deleted on one side but still used on the other, the same function written twice.

It never touches your working tree. Everything is computed from commits with git merge-tree and tree-sitter parsers, so it is safe to run in a pre-push hook, in CI, or from an AI coding agent over MCP.

What it detects

Semantic rules understand TypeScript, JavaScript (incl. TSX/JSX) and Python. Files in other languages still get the textual, add/add and modify/delete checks.

Install

mergelock needs git 2.38 or newer (for git merge-tree --write-tree).

Homebrew (macOS and Linux):

brew install sadayamuthu/tap/mergelock

Debian / Ubuntu (.deb, amd64 and arm64; needs a distribution with git 2.38+, such as Debian 12 or Ubuntu 24.04):

VERSION=0.1.4   # latest release, without the v
curl -fLO "https://github.com/sadayamuthu/mergelock/releases/download/v${VERSION}/mergelock_${VERSION}_$(dpkg --print-architecture).deb"
sudo apt install "./mergelock_${VERSION}_$(dpkg --print-architecture).deb"

Fedora / RHEL (.rpm, x86_64 and aarch64):

VERSION=0.1.4
sudo dnf install "https://github.com/sadayamuthu/mergelock/releases/download/v${VERSION}/mergelock-${VERSION}-1.$(uname -m).rpm"

Docker (linux/amd64 and linux/arm64; mount the repository at /repo):

docker run --rm -v "$PWD":/repo ghcr.io/sadayamuthu/mergelock check my-branch main --format text
docker run -i --rm -v "$PWD":/repo ghcr.io/sadayamuthu/mergelock   # MCP server on stdio

Prebuilt binary (macOS and Linux, amd64 and arm64): download the archive for your platform from the latest release, then put mergelock on your PATH:

tar -xzf mergelock_*_$(uname -s | tr A-Z a-z)_*.tar.gz
sudo mv mergelock /usr/local/bin/

Shortened. The full README is on GitHub.