# gRPC streaming

> HyperCore private-preview documentation.

> For the complete documentation index, see [llms.txt](/docs/llms.txt).

<Callout intent="info">
  This API is in private preview. Target September 2026; timing is subject to change.
</Callout>


# gRPC streaming

HyperCore gRPC provides block streaming and order-book streaming at price-level,
top-of-book, and order-level detail, plus trigger-order updates. Connection details and
generated client configuration will be published as the service is finalized.

## Available streams

| Stream | Delivers |
| --- | --- |
| [StreamBlocks](/docs/chains/hypercore-grpc/api-reference/stream-blocks) | Raw blocks, one message per block |
| [StreamL2Book](/docs/chains/hypercore-grpc/api-reference/stream-l2-book) | Aggregated price-level snapshots |
| [StreamL2BookDiff](/docs/chains/hypercore-grpc/api-reference/stream-l2-book-diff) | Incremental price-level changes |
| [StreamL4BookUpdates](/docs/chains/hypercore-grpc/api-reference/stream-l4-book-updates) | Per-order changes with queue position |
| [StreamBboBook](/docs/chains/hypercore-grpc/api-reference/stream-bbo-book) | Top-of-book best bid and offer |
| [StreamTpslUpdates](/docs/chains/hypercore-grpc/api-reference/stream-tpsl-updates) | Take-profit and stop-loss order lifecycle |

## Choosing a transport

WebSocket and gRPC can expose the same market data through different transports. Use
[WebSocket streams](/docs/chains/websockets/hypercore) when integrating with the
subscription envelope, and use [gRPC streams](/docs/chains/hypercore-grpc/getting-started/overview)
when integrating with the RPC service definition. For L2 books,
[l2Book](/docs/chains/websockets/hypercore/streams/l2-book) and
[l2BookDiff](/docs/chains/websockets/hypercore/streams/l2-book-diff) describe
complementary snapshot and diff representations.