Venue Adapters

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Overview

Venue adapters connect Notional’s event-driven architecture to external exchanges. The adapter pattern enables:

• Multi-venue support - Trade across multiple exchanges
• Unified interface - Consistent API regardless of venue
• Async execution - Non-blocking order submission
• Automatic reconciliation - Detect and correct state drift

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Architecture

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Hyperliquid Adapter

The primary venue adapter integrates with Hyperliquid, managing order submission, fill reconciliation, and connection reliability.

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Order Management

The adapter implements priority queuing and concurrent order limits (Hyperliquid supports max 100 concurrent orders). Priority System:

• System-initiated orders (liquidations): Priority 0 (highest)
• User orders: Priority 1

Queue Processing:

• Orders queued with priority
• Respects 100 concurrent order limit
• Converts internal format to Hyperliquid wire format
• Tracks in-flight orders by order ID

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Retry Logic

Exponential backoff: Delay = min(2^n × 100ms + Jitter, 10s). Maximum 5 retries before escalating to dead letter queue.

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Connection Reliability

WebSocket: Automatic reconnection with 30s heartbeat timeout. Position reconciliation on reconnect to verify state. Dual-channel architecture: REST for order submission (synchronous ack), WebSocket for fills (real-time).

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Fill Reconciliation

Matches venue fills to internal orders via order ID tracking. Handles out-of-order notifications and logs discrepancies for manual review.

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Event Flow

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Wire Format Conversion

Hyperliquid uses shortened field names for efficiency. Internal orders are converted to wire format: Internal Format:

• asset: Asset name (e.g., “BTC”)
• side: “buy” or “sell”
• limitPx: Limit price as string
• sz: Order size
• reduceOnly: Boolean flag

Hyperliquid Wire Format:

• a: Asset index (integer)
• b: Buy flag (true/false)
• p: Price (trailing zeros removed)
• s: Size
• r: Reduce only flag
• t: Time-in-force specification
• c: Client order ID (for tracking)

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Next Steps