GoldRush-native: No wss://api.hyperliquid.xyz/ws equivalent.
Pass builder (string) for a single builder or addresses (string[]) for many. aggregateByTime optional.
Live-only: No historical snapshot on subscribe. For windowed history, use the Info API builderFillsByTime
Same per-fill shape as userFills, plus builder and builderFee on every entry; channel name in messages is builderFills.
Subscribe to one builder address (builder) or many (addresses) and receive every fill routed through those builders as they execute, batched per block as [address, fill] tuples. Each fill carries the matched builder address and the corresponding builderFee.
Endpoint wss://hypercore.goldrushdata.com/ws?key=<GOLDRUSH_API_KEY>
Your GoldRush API key. Passed as a query parameter at connection time - no Authorization header is used.
Subscribe Send this JSON message after the connection is established. Provide either builder (single address) or addresses (array of addresses).
Single builder address (lowercase 0x-prefixed 42-character hex) to stream fills for. Mutually exclusive with addresses.
Array of builder addresses to stream fills for - the multi-builder form of builder. Mutually exclusive with builder.
When true, partial fills of the same order within the same block are merged into one. Default false.
Example wscat -c "wss://hypercore.goldrushdata.com/ws?key= $GOLDRUSH_API_KEY " > { "method" : "subscribe" , "subscription" : { " type ":" builderFills "," builder ":" 0xb84168cf3be63c6b8dad05ff5d755e97432ff80b "}}
import WebSocket from "ws" ; const ws = new WebSocket ( `wss://hypercore.goldrushdata.com/ws?key= ${ process . env . GOLDRUSH_API_KEY } ` , ); ws . on ( "open" , () => { ws . send ( JSON . stringify ({ method: "subscribe" , subscription: { type: "builderFills" , builder: "0xb84168cf3be63c6b8dad05ff5d755e97432ff80b" , }, })); }); ws . on ( "message" , ( raw ) => { const msg = JSON . parse ( raw . toString ()); if ( msg . channel === "builderFills" ) { for ( const [ address , fill ] of msg . fills ) { console . log ( address , fill . coin , fill . side , fill . sz , "@" , fill . px , "builderFee:" , fill . builderFee ); } } });
import asyncio, json, os import websockets async def main (): uri = f "wss://hypercore.goldrushdata.com/ws?key= { os.environ[ 'GOLDRUSH_API_KEY' ] } " async with websockets.connect(uri) as ws: await ws.send(json.dumps({ "method" : "subscribe" , "subscription" : { "type" : "builderFills" , "builder" : "0xb84168cf3be63c6b8dad05ff5d755e97432ff80b" , }, })) async for raw in ws: msg = json.loads(raw) if msg.get( "channel" ) == "builderFills" : for address, fill in msg[ "fills" ]: print (address, fill[ "coin" ], fill[ "side" ], fill[ "sz" ], "@" , fill[ "px" ], "builderFee:" , fill.get( "builderFee" )) asyncio.run(main())
Unsubscribe Send the same subscription body with method: "unsubscribe":
{ "method" : "unsubscribe" , "subscription" : { "type" : "builderFills" , "builder" : "0xb84168cf3be63c6b8dad05ff5d755e97432ff80b" } }
Unsubscribe matches subscriptions by exact body . A subscription created with builder: "0xAAA" is a different subscription from one created with addresses: ["0xAAA"], even if they target the same builder. To narrow a multi-builder set, unsubscribe the original list in full, then resubscribe with the smaller list.
Streamed message Each push has channel: "builderFills" and a fills array of [address, fill] tuples. The first element of each tuple is the trader who executed the fill; the fill object carries the trade details, including the builder it was routed through and the builderFee earned.
{ "channel" : "builderFills" , "fills" : [ [ "0x742d35cc6634c0532925a3b844bc9e7595f7f2e2" , { "coin" : "ETH" , "px" : "2150.5" , "sz" : "1.5" , "side" : "B" , "time" : 1704067200000 , "startPosition" : "1.5" , "dir" : "Open Long" , "closedPnl" : "125.5" , "hash" : "0xabc...def" , "oid" : 12345678 , "crossed" : false , "fee" : "2.5" , "tid" : 87654321 , "feeToken" : "USDC" , "twapId" : null , "builderFee" : "0.1" , "builder" : "0xb84168cf3be63c6b8dad05ff5d755e97432ff80b" } ] ] }
Tuples of [address, fill]. The address is the trader who placed the order; the fill object carries the trade details plus builder-attribution fields. Asset symbol - e.g. "BTC", "ETH" for perps; spot pairs use the @N form (e.g. "@107").
Fill execution price (decimal string).
Fill size (decimal string).
"B" for buy/long, "A" for ask/short.
Unix timestamp in milliseconds when the fill executed.
Signed position size the trader held on this coin immediately before this fill.
Human-readable direction label - "Open Long", "Open Short", "Close Long", "Close Short", "Buy", "Sell", or position-flip labels "Long > Short" / "Short > Long".
Realized PnL in USDC attributable to this fill for the trader (zero when the fill opens or extends a position).
L1 transaction hash that included this fill.
true when the fill came from the taker side of the order, false when it was the maker side.
Trading fee paid by the trader for this fill, denominated in feeToken.
Symbol the fee was paid in - typically "USDC".
Parent TWAP order ID if this fill is a slice of a TWAP, otherwise null.
Builder address the order was routed through - matches one of the subscribed builders.
Builder fee earned for this fill, denominated in feeToken.
Optional. Client order ID (0x-prefixed 32-character hex) if one was set at order placement.
Optional. Present only when this fill closed a position as part of a liquidation event. The wallet whose position was liquidated.
Mark price at the time of liquidation.
Liquidation method - "market" or "backstop".
Errors A missing or malformed builder/addresses field returns an error message on the same channel:
{ "channel" : "error" , "data" : "subscription builderFills requires a 'builder' field" }
allFills stream every fill on HyperCore in real time for global market analytics and cross-wallet order-flow…
liquidationFills stream a global, market-wide feed of every liquidation fill on HyperCore.
userFills stream real-time trade fills for one or more wallets as they execute on HyperCore.
Last reviewed: 2026-06-19 
