Core Assign Editor
Edit the systems, Libretro cores, External emulators, BIOS files and requirements in core.json in your browser, with the file opened and the finished JSON downloaded locally.
Install the finished file as MUOS/info/manifest/core.json. It replaces the bundled file, so begin with the current complete file and keep a backup. A valid file can still refer to a core, launcher, device, BIOS file, or catalogue that is not installed.
Select nothing to offer the core everywhere. Selecting entries limits it to those boards or builds. Hold Ctrl or drag to choose more than one.
Advanced core JSON
Use this for fields not represented above. Applying it replaces the selected core.
Advanced system JSON
Applying this replaces the selected system and preserves its system key.
Full core.json
This is the complete file. Apply changes here to return to the structured editor.