Comparing WebSocket and REST Data Streams for Real-Time Market Making

Introduction

In the fast-paced world of crypto market making, the quality and timeliness of market data are critical. Automated liquidity bots rely on accurate, up-to-date information to place and manage limit orders. Two primary methods for accessing this data are WebSocket streams and REST APIs. While both serve the same fundamental purpose—delivering order book and ticker data from exchanges—they differ significantly in how they operate and the impact they have on real-time trading strategies.

This article compares WebSocket and REST data streams, focusing on their roles in supporting responsive, reliable market making bots like those managed with Atlas LP. We’ll explore their technical differences, practical implications, and best practices for teams aiming to optimize liquidity provision.

WebSocket vs REST: An Overview

WebSocket: Real-Time Data Streaming

WebSocket is a protocol that enables persistent, two-way communication between a client and server. For crypto exchanges, this means:

• Streaming updates: Order book changes and ticker updates are pushed to the client as soon as they occur.
• Low latency: Since data is delivered instantly, bots can react to market changes faster.
• Efficient bandwidth: After the initial handshake, only incremental updates are sent, reducing unnecessary data transfer.

REST API: Request-Response Model

REST (Representational State Transfer) APIs use individual HTTP requests to fetch data. In market making:

• Polling required: Bots must repeatedly request order book and ticker data at set intervals.
• Higher latency: There’s always a delay between the market event and the next data fetch.
• Stateless: Each request is independent; no persistent connection is maintained.

Impact on Automated Market Making

Responsiveness to Market Changes

For market making bots, the ability to respond quickly to market movements is essential. WebSocket streams provide near-instant updates, allowing bots to:

• Adjust limit orders in real-time as the order book evolves
• Cancel or replace mispriced orders promptly
• Seed new quotes efficiently when the market is empty

REST APIs, by contrast, introduce a delay that depends on the polling interval. Even with aggressive polling (e.g., every 0.5–3 seconds), there’s a risk of missing rapid changes, leading to:

• Orders resting at stale or unfavorable prices
• Increased exposure to adverse selection
• Reduced fill rates during volatile periods

Data Completeness and Reliability

WebSocket streams can occasionally drop messages or become desynchronized, especially if the client loses connection. Robust bots must detect and recover from these situations—often by fetching a full order book snapshot via REST to resynchronize.

REST APIs, while less timely, provide complete snapshots on demand. They’re essential for:

• Initializing the bot with a known-good state
• Recovering from WebSocket disconnects or data gaps
• Verifying that the live order book matches expected conditions

Bandwidth and API Rate Limits

WebSocket connections are generally more bandwidth-efficient for continuous updates, as only incremental changes are sent. REST polling can quickly hit exchange rate limits, especially on high-frequency intervals or with multiple symbols/accounts.

Market making bots must balance the need for fresh data with the risk of being throttled by the exchange. This makes WebSocket the preferred choice for real-time responsiveness, with REST as a backup and for periodic validation.

How Atlas LP Handles Data Streams

Atlas LP’s spot liquidity bot is designed to maximize data freshness and reliability:

• Order book and ticker data are read on every tick (as frequently as every 0.5 seconds, default 3 seconds).
• WebSocket streams are used when available, providing low-latency updates for supported exchanges.
• REST APIs serve as a fallback or for validation, ensuring the bot can recover from data gaps or connection issues.
• Stale or crossed data is detected: The bot skips ticks if the data is outdated or inconsistent, avoiding actions based on unreliable information.

This approach ensures that limit orders are placed, updated, or canceled based on the most accurate and current market conditions possible, within the constraints of each exchange’s API.

Best Practices for Teams Using Exchange APIs

1. Prefer WebSocket for real-time updates: Use WebSocket streams wherever possible to minimize latency and maximize responsiveness.
2. Monitor data quality: Implement checks for staleness, crossed books, or missing updates. Skip trading actions if data is unreliable.
3. Use REST for snapshots and recovery: Periodically fetch full order book snapshots to validate the current state and recover from WebSocket disconnects.
4. Respect API rate limits: Avoid excessive REST polling to prevent throttling or bans. Combine both methods for efficiency.
5. Secure API credentials: Always encrypt API keys and restrict permissions to spot trading and read-only access, never withdrawals.

Practical Example: Bot Tick Workflow

On each tick, a market making bot like Atlas LP will:

• Read the latest ticker and order book (via WebSocket or REST)
• Validate data freshness and integrity
• Compute the desired order ladder based on strategy settings
• Place missing limit orders and cancel excess or mispriced orders
• Sync open orders, recent fills, and balances

If the data is stale or crossed, the bot skips the tick, ensuring only high-quality information drives trading decisions.

When to Use Each Method

Conclusion

Choosing between WebSocket and REST data streams is not an either-or decision for market makers. The most robust bots use both: WebSocket for real-time responsiveness, and REST for validation and recovery. By understanding the strengths and limitations of each, crypto teams can build liquidity strategies that are both fast and reliable.

Atlas LP’s architecture reflects these best practices, ensuring that spot market making bots operate on the freshest data available while maintaining security and compliance.

Genuine market making means placing resting limit orders that any participant can trade against. Atlas LP prohibits wash trading, self-trading, and volume manipulation.

Atlas LP does not guarantee returns, prices, volume or listings.