CodePerfect
CodePerfect is a fast Go IDE, built from scratch in C/C++/OpenGL like a video game. It starts instantly, runs at 144 FPS, has near-zero latency, and comes with native, full-featured code intelligence and integrated debugging with Delve. See more features here.
It's no longer actively developed, but is now open source and free. It only supports MacOS; there are no plans to port it.
Build
sh/install_deps # Install dependencies
sh/build # Build raw binary to ./build
sh/package # Build CodePerfect.app (and zip) to ./scratch