Conformance and compatibility system

The Modeller.Conformance module turns accepted contracts into executable evidence. It accepts a versioned conformance fixture and an adapter for one public Modeller interface, then returns a normalized report without inspecting implementation structure.

Runner interface

ValueTask<ConformanceReport> ConformanceRunner.RunAsync(
    ConformanceFixture fixture,
    IConformanceAdapter adapter,
    CancellationToken cancellationToken = default)

An adapter declares its capability and contract version and receives only the fixture input, deterministic work and observation limits, and cancellation. The report is Passed, Mismatch, Invalid, Cancelled, or Failed and contains stable, path-specific mismatch diagnostics.

JSON object property order is normalized while array order remains observable. Permitted variance is restricted to operational data and rendered presentation text. Conclusions, findings, missing facts, explanations, canonical traces, semantic digests, ownership, and other semantic observations cannot be waived. Adapter exceptions are isolated and reported without exposing their messages.

Versioned evidence

The conformance directory contains:

• strict JSON schemas for fixtures and generated failure records;
• a stable diagnostic catalogue;
• a coverage manifest mapping accepted decisions to executable, adapter-pending, or planned fixtures;
• the compatibility support matrix;
• the explanation review rubric;
• the security threat inventory; and
• immutable curated and promoted regression fixtures.

Removing a supported schema or contract version is an explicit breaking decision. Historical fixtures are never regenerated from a current implementation.

Child Care fixtures

The initial corpus contains seven independently authored observations:

• the canonical-model ownership graph for the ACCS determination application;
• canonical loading and exact snapshot locking of the Child Care context package;
• staged rejection of an unknown ACCS eligibility Fact reference;
• readable ACCS source compiling to the canonical JSON semantic digest;
• Determine ACCS eligibility with sufficient facts and an Eligible conclusion;
• the same decision without supporting evidence, producing Information required, an explicit missing fact, a safe next action, and a canonical trace; and
• Classify ACCS eligibility selecting the Eligible decision-table row under the Unique hit policy.

All three evaluation fixtures retain versioned canonical JSON Child Care context packages and assert their normalized semantic digests. Each fixture also carries the SHA-256 digest of its own normalized input; loading a fixture whose input has changed without an explicit versioned update fails before an adapter runs.

The canonical-model, context-package, semantic-validation, readable-source, and three rules-runtime evaluation fixtures pass through real adapters over their public interfaces. Their expected domain meaning remains independently authored and is not regenerated from an adapter.

Generated and mutated scenarios

GeneratedConformanceRunner records generator version, seed, and a minimized reproduction whenever a deterministic generated scenario fails. SemanticMutationCheck requires an accepted baseline to pass and then proves that a deliberately changed implementation is detected. Agreement between implementations is supplementary evidence, never the expected-result oracle.

Release evidence

ConformanceEvidenceCatalog validates the diagnostic, coverage, compatibility, explanation, and security artifacts and exposes whether the implementation threshold is met. Individual capability releases must additionally turn their planned coverage entries executable and pass every applicable concurrency, cancellation, isolation, disclosure, compatibility, explanation, and trace gate.

The compatibility corpus begins with immutable unknown-future fixture-schema and persistence-schema artifacts and their expected safe rejections. New runtime, projection, and adapter versions add historical artifacts to the same corpus rather than regenerating old evidence.