--- title: 'Development' description: 'Preview changes locally to update your docs' --- **Prerequisites**: - Node.js version 19 or higher - A docs repository with a `docs.json` file Follow these steps to install and run Mintlify on your operating system. ```bash npm i -g mint ``` Navigate to your docs directory where your `docs.json` file is located, and run the following command: ```bash mint dev ``` A local preview of your documentation will be available at `http://localhost:3000`. ## Custom ports By default, Mintlify uses port 3000. You can customize the port Mintlify runs on by using the `--port` flag. For example, to run Mintlify on port 3333, use this command: ```bash mint dev --port 3333 ``` If you attempt to run Mintlify on a port that's already in use, it will use the next available port: ```md Port 3000 is already in use. Trying 3001 instead. ``` ## Mintlify versions Please note that each CLI release is associated with a specific version of Mintlify. If your local preview does not align with the production version, please update the CLI: ```bash npm mint update ``` ## Validating links The CLI can assist with validating links in your documentation. To identify any broken links, use the following command: ```bash mint broken-links ``` ## Deployment If the deployment is successful, you should see the following: Screenshot of a deployment confirmation message that says All checks have passed. ## Code formatting We suggest using extensions on your IDE to recognize and format MDX. If you're a VSCode user, consider the [MDX VSCode extension](https://marketplace.visualstudio.com/items?itemName=unifiedjs.vscode-mdx) for syntax highlighting, and [Prettier](https://marketplace.visualstudio.com/items?itemName=esbenp.prettier-vscode) for code formatting. ## Troubleshooting This may be due to an outdated version of node. Try the following: 1. Remove the currently-installed version of the CLI: `npm remove -g mint` 2. Upgrade to Node v19 or higher. 3. Reinstall the CLI: `npm i -g mint` Solution: Go to the root of your device and delete the `~/.mintlify` folder. Then run `mint dev` again. Curious about what changed in the latest CLI version? Check out the [CLI changelog](https://www.npmjs.com/package/mintlify?activeTab=versions).