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WebSocket streaming

This API is in private preview. Target September 2026; timing is subject to change.

Use the native subscription envelope: {"method":"subscribe","subscription":{...}}. Use the same subscription object with "method":"unsubscribe" to close a stream. Acknowledgements use "channel":"subscriptionResponse"; data frames use {"channel":"<type>","data":{...}}.

HyperCore data frames carry additive top-level metadata: subscriptionId, blockHeight, blockTime, and, on replay-capable streams, cursor.

FieldTypeDescription
channelstringSubscription-response channel or stream type.
dataobjectStream-specific payload.
subscriptionIdstringSubscription identifier.
blockHeightintegerSource-block height.
blockTimeintegerSource-block time.
cursorstringOpaque resume token on replay-capable streams.

Native subscriptions use singular coin and user fields. HyperCore's coins, users, builders, intervals, and eventTypes arrays are Alchemy extensions for multi-entity subscriptions. Candle subscriptions include both a coin dimension and an interval dimension.

StreamDescription
activeAssetCtxActive asset context.
allCandlesCandle updates across selected coins and intervals.
allFillsFill updates across selected coins.
allIsolatedMarginUpdatesIsolated-margin updates across the available stream scope.
allLeverageUpdatesLeverage-setting updates across the available stream scope.
allTwapStatusUpdatesTWAP-status updates.
allUserNonFundingLedgerUpdatesNon-funding ledger updates.
bboBest-bid and offer book updates.
builderFillsBuilder fill updates.
builderLiquidationBuilder-context liquidation updates.
builderOrderUpdatesBuilder order updates.
candlesCandle updates for selected coins and intervals.
fundingRatesFunding-rate updates.
l2BookL2 book snapshots.
l2BookDiffL2 book differences.
l4BookUpdatesL4 order-level updates.
liquidationFillsLiquidation fill updates.
setOracleUpdatesOracle updates.
tpslUpdatesTake-profit and stop-loss updates.
tradesMarket-wide trade events; use userFills for the same events scoped to an account.
userFillsUser fill updates.
userIsolatedMarginUpdatesUser-context isolated-margin updates.
userLeverageUpdatesUser-context leverage updates.
userNonFundingLedgerUpdatesUser non-funding ledger updates.
userOrderUpdatesUser order updates.

For connection, resume, and recovery behavior, see connection lifecycle and replay and recovery.

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