kernel, particularly around devices and the Styx/9P2000 protocol. Inferno shares with Plan 9 the Unix heritage from Bell Labs and the Unix philosophy. Many of the command line tools in Inferno were Plan 9 tools that were translated to Limbo. 9atom augments the Plan 9 distribution with the addition of a 386 PAE kernel, an amd64 cpu and terminal kernel, nupas, extra pc hardware support, IL and Ken's fs. 9front is a fork of Plan 9. It was started to remedy a perceived lack of devoted development resources inside Bell Labs, and has accumulated various fixes and improvements. 9legacy is an alternative distribution. It includes a set of patches based on the current Plan 9 distribution. Akaros is designed for many-core architectures and large-scale SMP systems. Harvey OS is an effort to get the Plan 9 code working with gcc and clang. JehanneOS is an experimental OS derived from Plan 9. Its userland and modules are mostly derived from 9front, its build system from Harvey OS, and its kernel is a fork of the Plan9-9k 64-bit Plan9 kernel. NIX is a fork of Plan9 aimed at multicore systems and cloud computing. node9 is a scripted derivative of Plan9/Inferno that replaces the Limbo programming language and DIS virtual machine with the Lua language and LuaJit virtual machine. It also replaces the Inferno per-platform hosted I/O with Node.js' libuv eventing and I/O for consistent, cross-platform hosting. It's a proof-of-concept that demonstrates that a distributed OS can be constructed from per-process namespaces and generic cloud elements to construct a single-system-image of arbitrary size. Plan B designed to work in distributed environments where the set of available resources is different at different points in time. License Starting with the release of Fourth edition in April 2002, the full source code of Plan 9 from Bell Labs is freely available under Lucent Public License 1.02, which is considered to be an open-source license by the Open Source Initiative (OSI), free software license by the Free Software Foundation, and it passes the Debian Free Software Guidelines. In February 2014, the University of California, Berkeley, was authorized by the current Plan 9 copyright holder – Alcatel-Lucent – to release all Plan 9 software previously governed by the Lucent Public License, Version 1.02 under the GPL-2.0-only. On March 23, 2021, ownership of Plan 9 transferred from Bell Labs to the Plan 9 Foundation, and all previous releases have