Feature contracts

For the 0.4.0 release and explicitly marked 0.5.0 development extensions, feature contracts are the observable-API and runtime-semantics part of the Vernac specification. That index provides the complete reading order and authority rules. Use the language reference for syntax and the tutorials for guided use.

Use the specification index for the full feature catalog. In this revision:

• Shared Java implementation rules: nullable parameters, external target resolution and Java overload identity (0.5.0 development).
• HTTP inbound adapters: request bindings, usecase invocation, response mapping and error defaults.
• Pagination: runtime APIs and offset/cursor JDBC queries; completed usecase results and HTTP DTO integration.

Additional implemented feature contracts

• Versioned modules: versioned exports/imports, explicit activation, provider selection, independent migrations and module-owned events/HTTP entrypoints.

• Ubiquitous language: namespaced terms, model association, hover, glossary output and exported-type documentation.

• Domain diagrams: resolved namespace graphs and shared Maven/IDE exports.