klystron is a 2D game engine and toolchain that is begin created for the purpose of remaking Thrust. It provides low-level game logic such as collision detection, real time sound synthesis, file management and so on.
In addition, there are simple tools for editing tile based levels, packaging files and editing music (the music editor klystrack is a related, separate project).
These details are provided for information only. No information here is legal advice and should not be used as such.