Roblox is one of the most successful games of all time and a key part of that success is enabling their users to create their own worlds. When Roblox was started back in 2006, the programming language end users (and Roblox themselves) used was Lua. Over time, Roblox have made several changes and improvements to the Lua programming language to better suite game development, and the resulting language Luau was just open sourced under the MIT open source license. Luau is derived from (but not a super set of) the Lua 5.1 programming language with several game development oriented features added.
Details of the open sourcing of the Luau programming language from the announcement post:
Luau is a new language that started from Lua 5.1 and kept evolving while keeping backwards compatibility and preserving the original design goals: simplicity, performance, embeddability.
We’re incredibly grateful for the foundation that Lua has been—it’s been a joy to build on top of! So now we want to give back to the community at large.
Starting today, Luau is no longer an inseparable part of Roblox platform; it’s a separate, open-source language.
Luau is available at https://github.com/Roblox/luau and comes with the source code for the language runtime and all associated tooling: compiler, type checker, linter. The code is available to anyone, free of charge, under the terms of MIT License. We’re happy to accept contributions to the language, whether that’s documentation or source code.
The language evolution is driven by an RFC process that is also open to the public.
Luau Open Source Announcement
Luau Language Homepage
Luau GitHub Page
You can learn more about the new game programming focused open source Luau language from Roblox in the video below.