This section covers the core building blocks you can mix and match or use together as a complete scalable backend for onchain apps.

Indexer

Real-time balances, transfers, prices, and contract events across EVM chains. Low-latency reads with webhooks and event subscriptions.

Transaction API

Unified relayer/dispatcher for sending transactions with gas sponsorship, batching, and parallel nonces. Compatible with any EVM contract.

Blockchain RPC

High-availability node access via the Sequence Node Gateway. Health-checked, auto-routed RPC across providers with minimal config.

Sidekick

Dockerized backend for secure key management and standardized read/write endpoints (e.g., mint, transfer) using Sequence infrastructure.

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How these fit together

  • Read fast with Indexer; subscribe to changes via Webhooks or Event Subscriptions.
  • Write reliably with Transaction API using gas sponsorship, optimal gas pricing, and automatic resubmits.
  • Call contracts or libraries directly through Blockchain RPC when you need raw node access.
  • Run server-side flows with Sidekick for secure key custody and simplified endpoints, or build your own server with our SDKs.