rgbuilder-graph Storage Architecture

The rgbuilder-graph crate stores the code knowledge graph: typed nodes and edges, secondary indexes, persistence, and a mini query language. Analysis algorithms live in rgbuilder-analysis.

Layers

Layer	Module	Role
Schema	`schema.rs`	`Node`, `Edge`, `NodeType`, `EdgeType`
Backend	`backend/memory.rs`	`MemoryBackend` — RwLock maps + indexes
Interning	`intern.rs`	`Arc<str>` dedup for index keys
Query	`query.rs`	Filter language (`type:Function`, compound `\|`)
Persistence	`snapshot.rs`, `columnar_snapshot.rs`	v1 bincode / v2 columnar mmap
API	`code_graph.rs`	`CodeGraph` wrapper

MemoryBackend

Nodes: HashMap<Uuid, Node> under RwLock
Edges: Vec<Edge> under RwLock
Indexes: name, type, label, property, edge-type
Query cache: invalidated on every mutation

Zero-clone APIs for analysis: edge_topology_typed(), for_each_node, find_node_ids_by_*.

Snapshots

Format	Version	Open cost
JSON	legacy	Full parse
bincode mmap	v1	Deserialize payload
columnar mmap	v2	Header + indexes only

v2 uses fixed-width rows (64 B node, 40 B edge) + string pool. BLAKE3 content_digest enables cache invalidation.

SQLite (blast-radius only)

rgBuilder does not store the knowledge graph in SQLite. The only SQLite usage is macro_call_index.db in rgbuilder-analysis — a precomputed blast-radius lookup cache written at discover and read by blast-radius T0 (MacroCallLookupDb). GQL, export, and metrics use the columnar mmap graph.

Downstream

MemoryBackend / ColumnarGraphMmap → rgbuilder-analysis::PetGraphView → algorithms