corvid documentation

corvid is an embedded, multi-modal data store for AI applications. One in-process dependency does vector search, full-text search, metadata filtering, and rank fusion — composed into a single fluent call instead of three services glued together in application code.

use corvid::{Db, Metric, Value, field};

let db = Db::open("memory.corvid")?;
let docs = db.collection("docs");

let mut doc = std::collections::BTreeMap::new();
doc.insert("category".into(), Value::Text("blog".into()));
doc.insert("body".into(), Value::Text("rust embedded database design".into()));
doc.insert("embedding".into(), Value::Vector(vec![0.1, 0.9, 0.2]));
docs.insert(b"post-1", &Value::Map(doc))?;

// Hybrid query: filter + vector + text, fused and reranked, in one call.
let rows = docs
    .query()
    .filter(field("category").eq(Value::Text("blog".into())))
    .vector("embedding", vec![0.1, 0.9, 0.2], 100, Metric::Cosine)
    .text("body", "rust embedded database", 100)
    .rerank_mmr(0.7)
    .limit(10)
    .run()?;
# Ok::<(), corvid::Error>(())

The filter runs before ranking, so it is a true predicate — the top-k is computed among matching documents, never a post-hoc trim.

Where to go next

• New to corvid? The tutorial walks from install through your first database to the hybrid query walkthrough.
• Writing queries? The corvid language covers the data model, the query builder, filters, aggregations, ordering and pagination.
• Choosing indexes? The indexes section explains every index family — scalar, compound, text, geo, vector (HNSW, quantization, PQ) — and when each serves.
• Coming from C, Node, or another language? Start at bindings; the C ABI is the frozen contract every binding codes against.
• Operating a deployment? Administration covers backup, dump/load, compaction, bulk load, feature flags and observability.

What corvid is — and is not

corvid is a personal experiment, built in the open: the engine has 1,000+ tests across four feature configurations, >96% line coverage, and a correctness-first design (filters are true predicates, indexes are never stale, writes are transactional). It is pre-1.0: the API and on-disk format change freely until 1.0, with dump/load as the migration path — never a silent format change.

Permanent non-goals: SQL, networking/replication in the engine, distributed transactions, a hosted service.

About these pages

This site is the canonical corvid documentation. Two generated reference pages — the construct reference and the error codes — are synced from the engine’s conformance manifests at each release; everything else is hand-maintained prose. Versioned snapshots live under /vX.Y.Z/; see About these docs for the versioning mechanism.