@mildastudio/milda

The Milda language - a platform-neutral design language for describing design systems and their components, and the canonical AST that tools exchange.

Milda separates what a component is (its contract, anatomy, behavior, and styling intent) from how any one platform realizes it. A description written once can be generated into React, CSS, Figma variables, and - by design - other targets, without the description itself leaking platform assumptions.

This repository is the public, open-source mirror of the packages/milda package from the Milda monorepo, which stays the single source of truth. See milda.dev for the product and the full DSL documentation.

Install

npm install @mildastudio/milda

import { preludeV0, validate, resolveToken } from "@mildastudio/milda";

What's in here

• Spec (spec/) - the normative language: PRELUDE.md (source of truth), GRAMMAR.ebnf, ast.schema.json, ROADMAP.md, the language design proposals/, and examples/ (validate them with node spec/validate.js).
• AST (types/ast.ts) - the canonical interchange artifact. The spec in spec/PRELUDE.md is the normative source of truth; this package is one implementation of it.
• Tokens (types/tokens.ts) - layered, context-aware token values (color, dimension, shadow, typography, ...) with alias chains and an explicit escape leaf for values a target can't express natively.
• Facets, layout, states, capabilities (types/facets.ts) - the platform-neutral styling and layout vocabulary.
• Prelude (prelude/preludeV0.ts) - the standard library expressed as data: behavior atoms, archetypes, facets, states, and capabilities.
• Engine (engine/*) - pure, side-effect-free semantics over the AST: resolveToken, resolveFacets/resolveLayout, validate, and conformance (which reports where a description has holes for a given target).

Design invariants

• Platform-neutral by construction. Facet and token resolution is a pure structural merge; nothing here encodes CSS pseudo-classes, DOM tags, or any single platform's model. Target-specific lowering lives in the generators, not in the language.
• Honest escape hatches. Where a value or capability can't be expressed cleanly, the model carries an explicit escape leaf rather than silently approximating - so conformance can tell you exactly what won't survive a given target.

Where it fits

@mildastudio/milda is the language layer. The generators and pipeline that consume it live in the milda-engine repo (@mildastudio/core, @mildastudio/contract, @mildastudio/generate, @mildastudio/release), which depends on this package.

Status

0.x - the language and AST are still evolving; treat the shape as unstable until 1.0.

License

MIT