kaiHEN brings a homebrew environment and minimal CFW to Switch 2, with hbmenu, FTP and a devkit
kaiHEN is a homebrew environment and minimal custom firmware for Switch 2. It starts from one of the entry routes that already exist for the console and opens hbmenu with full system access, NAND included. Its own author warns that it is a work in progress.
What kaiHEN is
The repository was created on November 13 and the project's full name is kaiHEN改変. It describes itself as a homebrew environment and minimal custom firmware for Switch 2, under GPL-2.0. It deals with what comes after running code on the console: loading programs.
It has four parts. ro is an ldr:ro service that maps NROs into its clients' processes and publishes JIT code for them. bootstrap is the startup program that starts HEN and the plugins. hen is the resident service that starts the homebrew loader and gives each program its own session. libkaihen is the API for developers, with JIT support.
How it starts
The README says HEN is started from the acquisition tools available for Switch 2. After that you open a native game while holding R. From the second launch on, the console goes straight into hbmenu. It does not say which firmwares it works on: that depends on the entry route you use.
The two published releases, 20261114c and 20261114d, bundle bootstrap.bin, hbmenu, the homebrew loader and OunceShell, a file manager with an FTP server (VitaShell ported to Switch 2). The second swaps the FTP server for ftpd's: the SD card sits at the root, listings no longer slow down with several connections open, and MLSD, MLST and NLST work. As a known issue, names with non-ASCII characters, such as accents or Japanese, do not show in listings, although the files can still be opened, downloaded and deleted by name.
For developers
The ounce-devkit adds Switch 2 to a devkitPro installation, with libounce, which is libnx-compatible, and OunceVK, with Vulkan, EGL, OpenGL and OpenGL ES. According to the README, Switch 1 homebrew that uses libnx and OpenGL or Vulkan can be compiled for Switch 2 with it.
The project itself warns that it may have bugs and that it gives full access to the system, NAND included. A malicious homebrew could leave the console unusable for good. Install only programs from authors you know, and back up your saves.
