whatsdiff tells you what changed in your dependencies after a composer update or npm update. It reads your composer.lock and package-lock.json, compares them across your git history, and reports which packages were added, removed, updated, or downgraded, along with the release notes behind each version bump.
It ships as two things: a CLI and an MCP server.
The CLI
Install it, then run it in your project:
whatsdiff analyse
You get a summary of every dependency change. From there, changelog pulls the release notes, audit lists known security advisories, check answers yes or no questions inside a CI job, and tui opens the whole thing in an interactive terminal interface.
The MCP server
The same package installs whatsdiff-mcp, a Model Context Protocol server that gives your AI assistant four tools for querying Packagist and npm: compatible versions, release notes, available upgrades, and dependency constraints. Ask it which versions of Livewire work with Laravel 11 and it answers from real registry data instead of guessing.
GitHub app
A GitHub app that reports dependency changes directly in your pull requests is on the way. Get notified when it ships.
Contributing
Found a bug, or want a feature? Open an issue or send a pull request on GitHub.