@untheme/terrazzo

Codegen from DTCG (2025.10) design token JSON to an untheme.config.ts. A terrazzo plugin and a programmatic generate() share one pipeline: the resolver document's modifiers become untheme's axes, aliases survive as live references, and the output is validated against untheme's own schema — including a round-trip proof that Terrazzo's resolution and untheme's composition agree on every token at every selection.

Token names keep their DTCG dotted paths (color.primary.600); the CSS renderer dashes them into custom properties. Theme documents are plain DTCG token files that rebind a subset of the base contract — each becomes a layer in the generated catalog. The default export is the configuration (theme and input); the catalog is a named themes export, proven against the config's contract, for whatever serves it — the Nuxt module's themes option, a catalog provider, or a hand-rolled switcher.

Plugin

// terrazzo.config.js
import { defineConfig } from "@terrazzo/cli";
import untheme from "@untheme/terrazzo";

export default defineConfig({
  tokens: "./tokens.resolver.json",
  plugins: [
    untheme({
      themes: [{ source: "./themes/dark-ocean.json", name: "Dark Ocean" }],
    }),
  ],
});

tz build writes untheme.config.ts into the output directory. Theme documents resolve against the first token source and load without credentials.

Programmatic

generate() owns parsing, so a caller-supplied req can authenticate every document the parse touches — remote resolver, referenced sets, and theme documents alike. It returns the file contents; the caller owns I/O.

import { generate } from "@untheme/terrazzo";

const { filename, contents } = await generate({
  source: "https://api.example.com/v1/orgs/acme/resolver.json",
  req: async (src) => {
    const response = await fetch(src, {
      headers: { authorization: `Bearer ${key}` },
    });
    return response.text();
  },
});

Boundaries

• Terrazzo's beta token types (boolean, string, link) are off-spec and fail codegen by name; $extends is ignored.
• A theme or context may only rebind base tokens, never add them.
• Every modifier needs a default context — untheme boots one context per axis.
• Token names that would collide as CSS custom properties (a.b vs a-b) fail codegen.