DEV CommunityTuesday · June 16, 2026FREE

Fixing WebSocket Silent Disconnects for Financial Market Data

The article addresses the challenge of silent WebSocket disconnects, where a connection drops without triggering an error event, leading to stale data being served to users. This is particularly critical for financial market data applications where real-time accuracy is essential. The author describes implementing a heartbeat mechanism: the client sends periodic ping messages and expects pong responses within a timeout window. If no pong is received, the client assumes the connection is lost and initiates a reconnection sequence. The solution also includes exponential backoff for retries to avoid overwhelming the server. The author notes that this approach has been tested in production with multiple data feeds, including those from major exchanges. A key consequence is that traders receive accurate, up-to-date market data, preventing trades based on outdated information. The article emphasizes that standard WebSocket libraries often do not handle silent disconnects out of the box, making custom heartbeat logic necessary for reliability.