Cuis: The Modern Smalltalk-80

Cuis is a free Smalltalk-80 programming environment built around a goal of combining simplicity with power. It is designed to run across platforms while remaining fast and efficient. Its development tools support interactive work: programmers can inspect live objects, send them messages, browse classes, use code completion, and see execution feedback in a Transcript. A Workspace can hold and run code alongside the application being developed. Cuis also supports vector graphics, SVG, TrueType fonts, and Unicode, extending its use beyond conventional text-based software. The project presents itself as a clean, adaptable environment for building and exploring software, and includes favorable comments from Smalltalk figures such as Alan Kay, Dan Ingalls, and John Maloney.

Cuis is maintained by Juan Vuletich and a broader community that shares releases, demonstrations, and development work. The site announces the stable Cuis 7.8 release and community activity, including a planned demonstration of using a code agent to develop Blueprint, a reworking of the Cuis desktop. It also highlights a redesigned website, a Stream Deck plugin for controlling Cuis, and improvements to the Dybo tools. Cuis will feature prominently at Smalltalks 2026, with eight conference talks either coming from its community or presenting work done in the environment. Together, these details show a project that combines a long-standing Smalltalk model of interactive programming with ongoing work on tools, usability, and community collaboration.