Valve is currently in the process of developing the Lepton toolkit, which allows users to play Android platform games on Linux. This project is specifically created for integration with the Steam Client and aims to enable the running of Android games with virtual reality support on the Steam Frame VR helmet that runs on Linux.
Lepton functions as an isolated container with the system image of the Android platform, encompassing all necessary components for running Android games. It consists of patches and elements from various projects like Waydroid, Anbox, Halium, and Hybris. The tools for constructing the Android image for gaming on Linux are distributed under the GPLv3 license, while the tools for managing the game launching process with a prepared image fall under the MIT license.
Furthermore, Lepton offers additional features to aid game developers in porting their Android games to Steam. It transfers host OS libraries to the Android environment it creates, as well as Steam/Steamworks, graphics drivers like mesa and zink, and Vulkan layers to enhance rendering performance and reduce screen detail. The toolkit also supports integration with debuggers such as strace, gdb, lldb, renderdoc, and profilers like perfetto.
Key differences between Lepton and existing projects that provide environments for running Android applications on Linux include running under an unprivileged user, thus eliminating the need for root rights for settings and actions. Additionally, all processes in Lepton are launched under one unprivileged user, with each Android game assumed to run in a separate Android container. Notably, Lepton is tailored specifically for gaming purposes, containing only essential functionalities needed to run games and disabling unnecessary Android services. It also caches various component states to expedite the launch of Android environments.