Key Notes
- ns2jb is a software-only Switch 2 jailbreak for firmware 23.0.1 that the researcher says enables homebrew, game modifications and save backups.
- Codex helped with research and a Mario Kart World demonstration, but the researcher says the jailbreak required around two weeks of substantial human effort.
- The jailbreak must be rerun after restarting the console and is not a complete custom-firmware release.
Researcher pepsipu has demonstrated a software-only Nintendo Switch 2 jailbreak developed with help from the AI coding agent Codex. The project, called ns2jb, targets firmware 23.0.1, described in the researcher’s technical account as the latest version at the time. It enables homebrew software, game modifications and save backups without installing a modchip.
The public demonstration centers on a modified copy of Mario Kart World, a Switch 2 exclusive. In footage shared with the announcement, characters including Cinnamoroll and Hatsune Miku appear alongside other custom additions. The researcher says Codex produced the Mario Kart modification in a day, separately from the longer work needed to develop the jailbreak.
Codex was connected to a setup that could receive the consoles’ video output and send controller inputs. A Bluetooth button-pushing device handled physical restarts after crashes, allowing the software to continue testing. That external lab equipment supported the research process; it should not be confused with a chip installed inside the console.
The researcher also clarified that a caption suggesting a single prompt had autonomously jailbroken the system was a joke. The initial attempt at autonomous code execution did not succeed, and the jailbreak ultimately took around two weeks of substantial work. The account describes a human-led investigation using coding agents, rather than a finished console-unlocking tool created without supervision.
Important limits remain. The jailbreak is tethered, meaning it needs to be run again after the console restarts, and the work is intended to help the community progress toward custom firmware rather than supplying a complete custom-firmware release. The demonstrated ability to modify a game is also a narrower claim than unrestricted control over every part of the system.
