Yell replaces JSX with structured YAML. Every component is typed, versioned, and validated. AI agents and platform teams share one source of truth.
Live Editor
Edit the YAML on the left — see the rendered output on the right, instantly.
Why Yell
Yell was designed from the ground up to be generated, validated, and governed by AI agents.
YAML has strict indentation and structure. LLMs produce cleaner, more consistent output than with ad-hoc JSX.
Every component has a typed schema. Invalid props are caught at parse time, not runtime.
The linter blocks inline functions, ternary expressions, and function calls — keeping AI-generated YAML safe and predictable.
Tokens are defined once and referenced everywhere. AI uses them to generate consistent UIs without hardcoded values.
Render on the server, hydrate on the client. Selective hydration for interactive components only.
@yell/core, @yell/schema, @yell/ai-adapter, @yell/linter — each independently usable, all designed to work together.
Components
Define your design system in YAML once. Generate UIs with AI. Validate everything with schemas.