KNULLI

What KNULLI is

KNULLI is free, open-source custom firmware for supported retro-gaming devices, including handhelds and bartops. A fork of Batocera, it focuses on devices with unavailable or outdated kernel sources, limited GPU support, or devices selected by its team. It includes EmulationStation or Simplemenu/Simplermenu+ frontends, RetroArch, and multiple libretro cores, alongside RetroAchievements and netplay. Its scraper can retrieve game metadata and media from ScreenScraper, TheGamesDB, and ArcadeDB. Wireless and Bluetooth features, including audio, depend on the device; external USB wireless adapters can also be used. Syncthing can synchronize savegames between KNULLI devices or back them up to a NAS, but KNULLI has no cloud sync. Userdata is available over SMB for local-network transfers. Setup requires a device-specific image flashed to an SD card or internal storage, and games, BIOS files, saves, and themes must follow a strict, case-sensitive folder structure. The project warns that devices have no root password by default, leaving data accessible on the local network unless additional security is enabled.

Who it suits

KNULLI is for retro-gaming device owners whose specific hardware has a public release. It may suit users who want emulation features and local save synchronization, and who can follow device-specific installation and folder requirements.

Limits

The free firmware has public releases only for devices listed among the installation downloads; the project warns against using another device's package. Cloud sync is not available, and wireless or Bluetooth support depends on the device.

Getting started

1. Open the KNULLI website and find the installation package for your device.
2. Download the image for that device; do not use another device's package.
3. Flash the image to an SD card or the device's internal storage.
4. Place games, BIOS files, saves, and themes in the required case-sensitive folder structure.
5. Use the wiki for setup and troubleshooting guidance, or Discord for discussions.
6. Enable additional security to protect device data on the local network.

Verdict

KNULLI provides a free firmware option with emulation, metadata, and local save-sync tools for supported devices. Confirm that your device has its own release, and account for the required folder structure and default network-access warning.