Lightweight Celestia namespace indexer. Watches namespaces on the Celestia network, stores blobs and headers in SQLite, and serves them over JSON-RPC, gRPC, and REST.

• Dual data source: Index from a Celestia DA node (celestia-node) or directly from a consensus node (celestia-app)
• Backfill + streaming: Catches up on historical blocks, then streams live via header subscriptions with automatic gap recovery
• Query by commitment: Retrieve blobs by cryptographic commitment alone -- no height required
• JSON-RPC + gRPC: Celestia-node compatible JSON-RPC API alongside a gRPC API with server-streaming subscriptions
• Observability: Prometheus metrics, structured logging (zerolog), health/readiness endpoints
• Zero CGo: Pure Go, cross-compiles cleanly

# Generate default config (writes config.yaml)
apex init

# Set auth token (DA node mode)
export APEX_AUTH_TOKEN="your-token"

# Edit config.yaml: add namespaces, adjust URLs
# Start indexing
apex start

Requires Go 1.25+ and just.

just build          # compile to bin/apex
just test           # go test -race ./...
just lint           # golangci-lint
just check          # tidy + lint + test + build

• Running Apex -- setup, configuration, Docker, CLI
• API Compatibility Policy -- JSON-RPC compatibility boundary vs gRPC evolution

See LICENSE.