Architecture decisions

This page indexes the five accepted architecture decision records and summarizes the durable decision made by each.

• ADR-0001: Pull-based static HTTP transport — the index is built offline and the browser fetches immutable static files without a query-time backend.
• ADR-0002: JSON-first index format — JSON is universal while measured hot shard families can opt into an independent binary encoding.
• ADR-0003: BM25F ranking — BM25F with field, term, and document boosts is the implemented lexical ranking model.
• ADR-0004: Independent compatibility versions — package APIs use semver while the manifest uses a separately validated integer format version.
• ADR-0005: Opt-in feature boundary — small features remain bundled but data-gated, while materially heavy dependencies are separately and lazily loaded.

ADRs record accepted decisions, not every implementation detail. Proposed query-planner, storage, diagnostics, and plugin designs remain archived until a concrete consumer justifies revisiting them; see the roadmap.