CEM-ML is a declarative document lifecycle engine for structured content. It reads sources such as CEM-ML, CSV, JSON, YAML, CSS, and the HTML/XML family into typed, source-map-bearing AST/event streams; validates them against schema-package contracts; and then converts, transforms, formats, colors, or renders them through the same pipeline.

The project has two authoring layers. The core runtime is written in Rust and builds as a Linux-native CLI and as WebAssembly for browser hosts. The domain contracts are declarative: schemas, package manifests, formatter/colorizer resources, and transform templates are authored as CEM-ML and CEMT package assets rather than hard-coded as format-pair shortcuts.

For command-line users, cem-ml provides validation, conversion, transform graph execution, reports, terminal output, and HTML/SVG previews. For browser users, the same engine exposes an async WASM API used by Declarative Custom Element (<custom-element>) and the planned <cem-element> substrate, so declarative components can parse data, run transformations, and render light DOM without moving the document semantics into handwritten JavaScript.