OPAL can install O3DE either as a prebuilt binary or as a source build. Prebuilt engines are faster to get running; source builds let you patch the engine yourself. OPAL tracks which is which and only offers build actions where they make sense.
Installing a source build
On the Engine Downloads page, choose the Source platform filter (or a pre-release branch). OPAL downloads the engine source and runs the build through the Builds queue, so it’s pausable, resumable, and crash-safe like any other build.
Building and rebuilding
Source engines expose a Build action on the Engines page. Prebuilt engines don’t — the action is disabled with a “Cannot build pre-built engine” note, since there’s nothing to compile.
An unbuilt source engine is clearly marked so you know it still needs a build before projects can use it.
Script-Only mode
If you’re not compiling C++, turn on Script-Only mode (in the onboarding wizard or Settings). While it’s on, OPAL:
- Hides the Source option in Engine Downloads.
- Hides build actions on source engines.
- Notes that unbuilt source engines are unavailable in Script-Only mode.
This keeps the app focused on prebuilt, script-based work.