Scalos is a desktop replacement for the original Amiga Workbench GUI, based on a subset of APIs and its own front-end window manager of the same name.

Its goal is to emulate the real Workbench behaviour, plus integrating additional functionality and an enhanced look.

Scalos is a former commercial product originally written in 1999 by programmer Stefan Sommerfield for a software house called AlienDesign.

The purpose was to recreate the mouse-and-click experience on Amiga, offering an alternative to the Workbench interface present in versions 3.0 and 3.1 of AmigaOS (at that time already considered obsolete).

Scalos is a Workbench-compatible replacement which is declared by its developers 100-percent compatible with the original Amiga interface.