When you run Open Liberty in https://openliberty.io/docs/latest/development-mode.html[dev mode^], dev mode listens for file changes and automatically recompiles and deploys your updates whenever you save a new change. Run the following goal to start Open Liberty in dev mode:

[role=command]
```
mvn liberty:dev
```

After you see the following message, your Liberty instance is ready in dev mode:

[role="no_copy"]
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Press the Enter key to run tests on demand.
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Dev mode holds your command-line session to listen for file changes. Open another command-line session to continue, or open the project in your editor.
