What you see in the demo below is ClojureScript UIx app driving native window with ImGui UI via custom React reconciler. Both hot-reloading and REPL-driven development are supported, as you'd expect it from a typical ClojureScript project. The JavaScript side of the app runs in Hermes engine, which exposes ImGui to JS env. However, a release build of this exact app is a fully native 8MB executable. You can try it yourself on macOS or Linux . While Hermes engine is a JavaScript VM, it is also an AOT compiler for JavaScript that emits either Hermes byte code or C. Compiling this sample JavaScript program with Static Hermes: shermes -emit-c index.js print ( 1 + globalThis . value ); outputs the following C program or 50KB executable, when compiled straight into a binary shermes -Os index.js locals . t0 = _sh_ljs_get_global_object ( shr ); frame [ 3 ] = _sh_ljs_try_get_by_id_rjs ( shr , & locals . t0 , get_symbols ( shUnit )[ 1 ] /*print*/ , get_read_prop_cache ( shUnit ) + 0 ); locals .…