About Principia

Principia is, in its simplest form, a physics-based sandbox game. In Principia, you can build contraptions and simulate them in the physics simulation. This could be a mechanical contraption, an RC car, or a pinball game. Principia also contains a LuaScript object which allows you to write and create Lua programs that can interact with and affect the simulation.

Principia also features the Adventure game mode. In this game mode, you take control of a small robot which can do whatever you decide it to do. It can take part in a giant battle with enemy robots, or it can take control of the giant robot and wreak havoc on the world.

Principia was originally developed as a paid commercial game by the Swedish independent game company Bithack AB during 2013 and 2014, and was the sequel to the 2011 Android smash hit Apparatus. Sadly, Principia was later abandoned due to Bithack not being able to finance the project anymore because of low sales. It is however still loved by a small but passionate community that has kept the game alive after all these years.

In August 2022, Principia's source code was finally released onto GitHub and is now being further developed as an open source project by the community that grew up playing it. Principia is now free for everyone to download, use and modify under the terms of the BSD 3-Clause license. The game is currently available play on Windows, Linux, Android, as well as experimental ports to other platforms.

There are tens of thousands of user made creations by the community to play and enjoy. Browse the latest that the community has made right now, or browse the full collection of 25000+ levels from 2013 to 2018 on the Principia official community site archive.

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Gallery

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About principia-web

This website is the community site for Principia, providing a platform for sharing user created levels and interacting with the Principia community.

Principia-web originally started as an unofficial community site replacement by ROllerozxa after the official community site operated by Bithack shut down in 2018. It has since turned into the primary community site for the game after the source code release, created by the community for the community. To read more about the history of principia-web read this blog post written by ROllerozxa.

The source code powering principia-web, as well as related web infrastructure is freely available and open source.