Foundation for Sites 6 has had a long run. It was built for a web where CSS could not do layout on its own, and it papered over those gaps well. That web is gone. Container queries, cascade layers, native nesting, dialog, popover, light-dark(), and scroll-snap now cover most of what Foundation's Sass and JavaScript used to do.
So the next major version is not a port. It is a reimagining on the modern substrate, and it gets a new name to go with it: Yeti. The Yeti has been Foundation's mascot for years. Now it is the framework, and Foundation is the home for Yeti, Inky, and Proton.
What Yeti is
A CSS-first, native, zero-build layout and styling framework. One <link> tag and you're done. Named layouts instead of a column grid or utility classes. One token scale for type and space that recomputes at runtime. Dark mode and theming designed in from the first commit. Accessibility checked in CI. A machine-readable manifest that generates the docs, editor hints, and an MCP server so agents write correct markup.
No Sass. No required build step. No polyfills. Baseline 2025 browsers.
Licensing. Yeti ships under the Functional Source License 1.1 with an MIT future license (FSL-1.1-MIT). In practice: use it freely in your own sites and products, modify it, redistribute it; the one thing it reserves is offering Yeti itself as a competing product. Every release converts to plain MIT two years after it ships. Foundation for Sites 6 stays MIT.
What this means for you
- If you use Foundation for Sites 6: nothing breaks. Version 6 lives on the
v6 branch and keeps getting bug fixes. The foundation-sites npm package continues to publish 6.x from that branch. v6.9.0 is the final planned feature release.
- The
develop branch is now Yeti 7 and is unstable until the beta. Do not build on it yet.
- This repository will be renamed from
foundation-sites to yeti. GitHub redirects the old URL and git remotes, so existing clones and links keep working. Stars, forks, issues, and history all stay.
- Yeti ships as
yeti-css on npm when it reaches beta, versioned 7.0.0 to continue the sequence.
- Open issues and pull requests against 6.x are still welcome; retarget them at
v6.
Following along
The architecture and every phase spec live in this repository under docs/superpowers/. Progress is tracked in milestones. Questions go in Discussions; this issue stays pinned for announcements only.
Thank you to everyone who has built with Foundation over the years. Yeti is what Foundation would have been if CSS had been ready sooner.
Foundation for Sites 6 has had a long run. It was built for a web where CSS could not do layout on its own, and it papered over those gaps well. That web is gone. Container queries, cascade layers, native nesting,
dialog,popover,light-dark(), and scroll-snap now cover most of what Foundation's Sass and JavaScript used to do.So the next major version is not a port. It is a reimagining on the modern substrate, and it gets a new name to go with it: Yeti. The Yeti has been Foundation's mascot for years. Now it is the framework, and Foundation is the home for Yeti, Inky, and Proton.
What Yeti is
A CSS-first, native, zero-build layout and styling framework. One
<link>tag and you're done. Named layouts instead of a column grid or utility classes. One token scale for type and space that recomputes at runtime. Dark mode and theming designed in from the first commit. Accessibility checked in CI. A machine-readable manifest that generates the docs, editor hints, and an MCP server so agents write correct markup.No Sass. No required build step. No polyfills. Baseline 2025 browsers.
Licensing. Yeti ships under the Functional Source License 1.1 with an MIT future license (FSL-1.1-MIT). In practice: use it freely in your own sites and products, modify it, redistribute it; the one thing it reserves is offering Yeti itself as a competing product. Every release converts to plain MIT two years after it ships. Foundation for Sites 6 stays MIT.
What this means for you
v6branch and keeps getting bug fixes. Thefoundation-sitesnpm package continues to publish 6.x from that branch. v6.9.0 is the final planned feature release.developbranch is now Yeti 7 and is unstable until the beta. Do not build on it yet.foundation-sitestoyeti. GitHub redirects the old URL and git remotes, so existing clones and links keep working. Stars, forks, issues, and history all stay.yeti-csson npm when it reaches beta, versioned 7.0.0 to continue the sequence.v6.Following along
The architecture and every phase spec live in this repository under
docs/superpowers/. Progress is tracked in milestones. Questions go in Discussions; this issue stays pinned for announcements only.Thank you to everyone who has built with Foundation over the years. Yeti is what Foundation would have been if CSS had been ready sooner.