Jokosher is a multi-track non-linear audio editor with a prime focus on usability. It is developed in Python and is Open Source.
overview macos video editing
PiTiVi allows users to easily edit audio/video projects based on the GStreamer framework: Capture audio and video; mix, resize, cut, apply effects to audio/video sources
Diva is a project to build an easy to use, scalable, open-source video editing software for the Gnome desktop.