It did not allow true Homebrew to run on the system at the time, but it let developers look for other security bugs in the system. On October 1, 2017, ReSwitched announced many new exploits and tools allowing developers to start working on Homebrew programs for the system even before they could be launched. At the 34c3 event, hackers Plutoo, Derrek, and Naehrwert announced a kernel exploit for the system (which they said would not be released) and said that a Homebrew launcher was coming soon. On January 7, 2018, fail0verflow posted a video to Twitter showing a simple side-scrolling text program before booting the system, which shows that there is a way to run code before boot, opening up possibilities for new programs focused on development. A Homebrew launcher application has been released as well, and a custom firmware called Atmosphere, has also been released. Access to a Japanese copy of Puyo Puyo Tetris is initially required to install a Fake News exploit to launch the CFW on 1.0.0. For later system versions, the ability to install depends on the age of the console, as new consoles first appearing in June 2018 and shipping with system version 4.1.0 have their bootroms patched against the TrustZone (full control) exploit that allows CFW to be installed. As long as the system does not have the patches (which can only be installed at the factory during console assembly), the exploit can be used to install CFW. On March 29, 2018, SciresM, a respected developer in the Homebrew community, announced that custom firmware called "Atmosphere" would be released for all available firmware versions at the time. Firmware above 1.0.0 will be hackable via a cold boot exploit known as Fusée Gelée developed by the Reswitched team. This exploit takes advantage of a bug in the boot ROM on the Tegra X1 chip used by the Nintendo Switch. The exploit was also independently discovered by Fail0verflow under the name ShofEL2. Firmware version 1.0.0 will be hackable via a Trustzone exploit known as Jamais Vu. Atmosphere released its first public build in October 2018, which supports all system versions. The Xbox One has a Dev Mode, though intended to be used for retail game development, can be used to run unsigned Homebrew software. It can be enabled on any retail Xbox One console.