As soon as I saw the screenshot, I instantly knew it was using Dear Imgui library [1] under the hood because of the familiar Imgui design cues. Dear Imgui is or

As soon as I saw the screenshot, I instantly knew it was using Dear Imgui library [1] under the hood because of the familiar Imgui design cues. Dear Imgui is originally meant to be used in combination with game & graphics engines which support hardware acceleration. Thus, you get high framerates. [1]: https://github.com/ocornut/imgui https://github.com/ocornut/imgui