I know of two projects that need open source developers.
The Qub³D Engine Group is a brand new open source project that is building a cohesive, moddable, voxel-based game (similar to Minecraft), with a friendly community. They are using C++, OpenGL, Lua, and YAML, and are in the early stages of building. (I'm an advisor.)
More information can be found at their official website (pardon the dust, it's under construction). Development work takes place on their Phabricator, and chat via Discord. Links for both are on their website.
My own company, MousePaw Media, is looking for open source contributors to assist with three major projects:
Anari: An open source vector-based animation engine, which will be used as the backbone of a new game engine. (C++) We're also building the corresponding animation studio software, Lightrift (Python).
PawLIB: A collection of innovative C++ development tools, including...
Ratscript: an interpreted programming language aimed at game developers and designers, in which we're exploring some new syntactical ideas and (later) development paradigms. Ratscript is being built for our new game engine. Development on this will restart later this spring, if all goes well. (C++/Python)
More information about our open source work can be found at mousepawmedia.com/developers. Also, please consider emailing us at developers (at) mousepawmedia (dot) com to indicate your interest, so we can schedule collaboration.
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