Streaming Consumption API

The Streaming Consumption API is a push-based interface provided by satd, designed to serve downstream consumers such as wallets, Lightning nodes, exchanges, watchtowers, blockchain explorers, and other layer 2 projects. Its primary function is to deliver real-time blockchain event data, including blocks and mempool transitions, directly from the node to integrators who require timely and reliable updates.

A key feature of this API is its support for live, cursor-resumable watch subscriptions. These subscriptions can be keyed on outpoints, scripts, descriptors, and transaction IDs, allowing consumers to monitor specific blockchain elements with precision. The API addresses three common gaps found in other node consumption methods: descriptor lifecycle management, outpoint-level subscriptions, and cursor-based event replay. By offering these capabilities natively and in-process, the API provides consensus ground truth without relying on reconstructed data from external channels.

The Streaming Consumption API is particularly suited for integrators building infrastructure that depends on accurate and up-to-date blockchain event information. Example use cases include detecting Lightning channel closures, triggering watchtower actions, confirming exchange deposits, and monitoring for potential theft. The API's design centers on outpoint subscription as the foundational primitive, enabling a wide range of monitoring and automation scenarios.

Technical details, including the wire-level protocol specification, protobuf definitions, frame formats, and cursor semantics, are documented in the project's reference materials. The API is part of satd, which is described as a Bitcoin Core-compatible full node implemented in Rust.