Architecture

Use this page to understand tq's architecture boundaries.

ADR usage in this project

tq uses Architectural Decision Records (ADRs) to capture significant architecture decisions.

ADRs are stored in docs/adr/.

tq is a layered, deterministic static analysis tool for test quality:

Shared domain model: crates/tq-core owns validated runtime types such as target names, package names, target-relative paths, rule IDs, and shared enums so invariants are parsed once at boundaries and preserved across crates.
Composition root: crates/tq-cli/src/main.rs resolves config, validates targets, plans target runs, constructs rules, executes the engine, and selects the output reporter.
Config boundary: crates/tq-config owns strict config loading, precedence, validation, and materialization into runtime target config.
Discovery boundary: crates/tq-discovery scans configured source and test roots into immutable analysis indexes.
Domain execution: crates/tq-engine plans target-scoped runs, enforces engine invariants, and aggregates deterministic findings.
Rule implementations: crates/tq-rules contains the built-in rule registry, rule selection, and focused rule implementations with stable rule IDs.
Output adapters: crates/tq-reporting renders text and JSON output without pulling reporting concerns into the engine.
Tooling adapters: crates/tq-docsgen and crates/tq-dev own docs generation and the developer harness (repository policy, dependency maintenance, and release builds) so repository tooling follows the same Rust-first architecture as the runtime.

The core design emphasizes strict boundaries, immutable analysis inputs, stable rule contracts, and deterministic output ordering.