# wesnoth-map-diff > 🗺 Print the diff between two maps ## Setup 1 - Make sure you have Node on your system. If you don't have it, install it. If you are using macOS or Linux, you can install Node using [nvm](https://github.com/nvm-sh/nvm). On Windows, use [nvm-windows](https://github.com/coreybutler/nvm-windows). 2 - Open the terminal on `utils/wesnoth-map-diff` folder and run the following command to install the project dependencies: ``` npm i ``` 3 - Then, run the following command to build it: ``` npm run build:dev ``` 4 - Finally, run it using `node ./build/index.js [path for the old map] [path for the new map] [output filename]`. For instance: ``` node ./build/index.js old.map new.map output.png ``` ## Contributing Run tests: ``` npm run test ``` Run lint: ``` npm run lint ```