Native components
Standard custom elements, properties, and DOM events. Use them in plain HTML or alongside your existing framework.
A shared stamp.
Your own identity.
Siegel is the UI foundation for tailored software. Reusable components that people and AI agents compose around the way your application works.
A shared foundation.
An illustrative composition of the interface building blocks.
Consistency
without uniformity.
Siegel takes its name from the Hanseatic seal: a shared stamp that makes something recognisable. Its UI components have defined behaviour and documented interfaces, giving people and AI agents consistent parts to build with.
Compose forms, tables, navigation, and other interface components around your application’s workflows. Pair them with Rustlet backend building blocks to develop a complete solution. OpenHanse Cloud and Barkeeper put that approach into practice.
Built on the browser.
Familiar standards. A foundation you own.
Shared tokens
A consistent language for colour, spacing, and type, with light and dark themes and interaction density that follows the pointer.
Direct delivery
The core kit has no external dependencies or build step. Serve the files you own, without a runtime CDN or package service.
A common language
for real work.
Application frames, navigation, tables, charts, forms, dialogs, and feedback share the same foundations. Compose them around the work your application needs to do.
The living gallery is both a component reference and a composed Siegel application, with examples you can adapt. The source and integration guide explain how to host the kit and connect it to your service.
Start with the documentation