Automating the assembly of the engine and its execution into a single task. If you are modifying standard libraries, engine sources or Enso tests, you can launch `sbt` and then just:
```
sbt:enso> runEngineDistribution --run test/Tests/src/Data/Maybe_Spec.enso
[info] Engine package created at built-distribution/enso-engine-0.0.0-dev-linux-amd64/enso-0.0.0-dev
[info] Executing built-distribution/enso-engine-...-dev/bin/enso --run test/Tests/src/Data/Maybe_Spec.enso
Maybe: [5/5, 30ms]
- should have a None variant [14ms]
- should have a Some variant [5ms]
- should provide the `maybe` function [4ms]
- should provide `is_some` [2ms]
- should provide `is_none` [3ms]
5 tests succeeded.
0 tests failed.unEngineDistribution 4s
0 tests skipped.
```
the [runEngineDistribution](3a581f29ee/docs/CONTRIBUTING.md (running-enso)) `sbt` input task makes sure all your sources are properly compiled and only then executes your enso source. Everything ready at a single press of Enter.
# Important Notes
To debug in chrome dev tools, just add `--inspect`:
```
sbt:enso> runEngineDistribution --inspect --run test/Tests/src/Data/Maybe_Spec.enso
E.g. in Chrome open: devtools://devtools/bundled/js_app.html?ws=127.0.0.1:9229/7JsgjXlntK8
```
everything gets build and one can just attach the Enso debugger.