GUI64 is a graphical user interface for the Commodore 64, first released in version 1.0 in November 2024. Although it may appear to be a standalone operating system, it is just a graphical layer running on top of the C64’s built-in ROM-based operating system, the Kernal. The current version is 2.1.
GUI64 presents files and directories in freely movable windows, enabling easy file management on floppy disks as well as on disk images stored on SD2IEC devices. When running on an Ultimate device, all settings are saved and disk images can be mounted directly from within the GUI.
The software can be operated using a mouse such as the 1351 connected to Control Port #1, or with a joystick in Control Port #2. Mouse wheel support requires the Micromys adapter and also works with the VICE emulator. Starting with version 1.9, GUI64 offers two variants: a Windows-like interface with a taskbar and task buttons, and a Mac-like interface imitating early Apple Macintosh computers.
Unlike GEOS or C64OS, GUI64 does not use the VIC-II’s bitmap graphics mode but operates in text mode, making it character set–based. Windows are aligned to the 8×8-pixel grid rather than moved pixel-perfectly.
Drive icons default to device numbers 8 and 9. If an Ultimate cartridge is connected, a third desktop icon provides access to USB flash drive or SD card file systems, allowing disk images to be mounted directly from within GUI64.
Source: Hacker News · Summarized by HeadlinesBriefing