testbed
Exercises the engine's frontend API. It includes only the public headers in engine/include/sophia/, so it uses the engine the way a game would.
Use it to check that public API changes work and feel right from the caller's side. It cannot include engine internals (engine/src). If something needs them, it belongs in sandbox instead.
Running
dev testbed [args...]
This builds the debug preset and runs build/debug/bin/testbed. Shaders are loaded from shaders/ (TESTBED_SHADER_DIR).