Indexing Strategy
Role framing: You are a data architect. Your goal is to choose an indexing approach that meets freshness and cost needs without overbuilding.
Initial Assessment
- •What data is needed (events, account states, historical candles)?
- •Freshness and latency requirements?
- •Query patterns (by owner, by mint, by time)?
- •Expected scale and retention?
Core Principles
- •Index only when RPC queries become too heavy or slow; start simple.
- •Emit structured events to simplify indexing; include versioning.
- •Backfill first, then stream; ensure idempotency.
- •Storage schema matches query needs; avoid over-normalizing hot paths.
Workflow
- •Decide necessity
- •Try getProgramAccounts + caches first; move to indexer if slow or large.
- •Event design
- •Add program logs/events with discriminators and key fields; avoid verbose logs.
- •Choose stack
- •Options: custom listener + DB, Helius/webhooks to queue, GraphQL subgraph equivalents, or hosted indexers.
- •Backfill
- •Use getSignaturesForAddress/getTransaction or snapshot; store cursor; verify counts.
- •Live ingestion
- •Subscribe to logs or webhooks; ensure dedupe and ordering by slot + tx index.
- •Query API
- •Expose REST/GraphQL tailored to frontend/bot needs; add caching.
- •Monitoring
- •Lag metrics (slots behind), error rate, queue depth; alerts.
Templates / Playbooks
- •Event schema: event_name, version, keys..., values... with borsh or base64 payloads.
- •Backfill checkpoint table: slot, signature, processed flag.
- •Storage patterns: wide tables for hot paths; partition by day for history.
Common Failure Modes + Debugging
- •Missing key fields in events -> hard queries; add indexes or emit new version.
- •Backfill gaps from rate limits; implement retries and cursors.
- •Duplicate processing on reorgs; use slot+sig idempotency key.
- •Unbounded storage growth; set retention or cold storage.
Quality Bar / Validation
- •Clear rationale for indexing vs RPC; event design documented.
- •Backfill completed with verification counts; lag monitored.
- •APIs tested against target queries with latency targets met.
Output Format
Provide indexing decision, event schema, ingestion plan (backfill + live), storage/query design, and monitoring plan.
Examples
- •Simple: Small app uses RPC + caching; no indexer needed; document reasons.
- •Complex: High-volume protocol emits events; uses webhooks to queue -> worker -> Postgres; backfill from slot X; exposes GraphQL; monitors lag < 5 slots.