Develop with live reload

Attach an applet project to your running panel and apply changes as you save. Start with a project created by the todo tutorial.

Start the development run

From the project directory, run:

just dev

The applet appears in the running panel. If a configured applet on that bar already resolves to the same desktop id, development takes over that slot. Keep the terminal open to see stderr and build errors.

Change options without restarting

For an applet that reads options.title, set devconfig.toml in the project to:

options = { title = "Groceries" }

Save it. The CLI prints options updated, and useOptions() receives the new object without restarting the process. This is the project's local configuration, separate from your panel configuration.

Change source and restart

Edit index.tsx and save. The CLI prints the changed file, runs just build, and restarts the applet. A failed build keeps the running applet. Changes under hidden paths, node_modules, build, and dist do not trigger source restarts.

Changing env in the local configuration also restarts the applet. Development runs do not restart on failure. If the applet stops after an error, fix the source and save, or type r followed by Enter in the development terminal to restart it. Type t and Enter to print the current tree as the panel holds it.

Press Ctrl-C to detach the development run. See the CLI reference for panel, output, zone, environment, and alternate configuration options.