Flag Delivery v2 (FDv2) is now generally available for the Java, Python, Go, Node.js, .NET, and Ruby server-side SDKs.  Relay Proxy support is also available.

FDv2 introduces several key enhancements:
Two-phase initialization: Start quickly from a polling data source, then synchronize from a long-lived streaming connection.

• Data-saving mode: Resume from a previously saved state during reconnects to reduce bandwidth and processing time.
• File-based initialization: Initialize from a local file first, then connect to LaunchDarkly APIs for updates.
• Automatic failover: Seamlessly switch to polling if the streaming connection fails.
• Custom configurations: Combine initializers and synchronizers to meet advanced redundancy or behavior requirements.
• Improved flag caching: When using a persistent store in non-daemon mode, flag data is no longer limited by cache TTL.

Together, these improvements make flag delivery faster, more reliable, and more adaptable across production environments.

Learn more:

Data-saving mode documentation