Prototype Contribution Paths

These guides are for contributors preparing to maintain, extend, or review Proto UI Prototypes. They start from the cataloged P-* and T-* graph rather than treating “write a new Prototype” as the default contribution.

Start from applicable P/T entities, implementation, and public projections. This path covers behavior fixes, regression coverage, docs, demos, and drift reconciliation.

Read Maintaining an Existing Prototype

Base already owns the protocol. The derived P adds design-language props, tokens, rules, visual anatomy, and an explicit compatibility boundary. This is the clearest current complete path for Prototype authors.

Read Projecting Base into a Design Language

This is advanced work. Existing governed Base subjects proceed from their current P/T graph. For a genuinely new Base identity, research, a candidate graph, draft entities, implementation probes, and tests may proceed first; the only unresolved semantic decision is whether to admit the independent subject into Base.

Read Implementing a Governed Base Semantic Slice

Every new public Prototype must appear on a reachable website page in the same pull request. The demo should consume the real public package export and prefer the Prototype’s own anatomy and triggers. Use minimal, explicitly disclosed external orchestration only when there is no natural trigger or public controls must be demonstrated. See the Prototype Author Checklist for delivery checks.

Proto UI does not admit a Base Prototype because a component name is familiar or a styled library wants an inheritance point. A Base subject must own an independent, cross-host, testable input-fact-to-observable-output path with substantive executable evidence.

If you are still deciding what kind of Prototype work you have:

1. Read Why You Usually Do Not Need a New Prototype
2. Use Writing a Custom Primitive Prototype to understand a leaf authoring entry inside a governed or candidate boundary
3. Continue to Writing a Compound Prototype when the governed or candidate subject is a family
4. For presentation and compatibility deltas, read Building a Styled Library on Top of Base
5. Follow How to Read Reference Implementations from P/T entities into source and public projections

These guides do not infer a general Adapter contribution workflow from the incomplete Module, Host Capability, and Adapter-profile catalog. See Adapter Contribution Guide Deferred for that boundary.

Use the Prototype Author Checklist before opening a pull request.

Prototype documentation coverage