Release Notes v2.4.0
Version 2.4.0 (combined with v2.3.0) introduces powerful pipeline editing capabilities, enterprise-grade Kafka authentication, and significant performance improvements. This release focuses on making GlassFlow more flexible, secure, and efficient for production workloads.
What’s New
⚡ Kafka Ingestion Performance Improvements
The Kafka ingestor has been significantly optimized for better performance:
- New Kafka library (franz-go) - Migrated to franz-go, a modern and more efficient Kafka client library
- Fine-tuned consumer parameters - Optimized Kafka consumer settings for improved batch processing performance
- Asynchronous NATS publishing - Messages are now published to NATS asynchronously, eliminating blocking operations and improving throughput
- Improved throttling - Better rate limiting and backpressure handling
- Efficient batch cleanup - Proper cleanup of processed batches to prevent memory leaks
These optimizations result in significantly higher processing speeds and better resource utilization, especially for high-volume data streams.
✏️ Pipeline Editing
GlassFlow now supports full pipeline editing capabilities, allowing you to modify existing pipelines without recreating them from scratch. The editing functionality was introduced in v2.3.0 and significantly enhanced in v2.4.0.
Editing a pipeline will stop the pipeline (stop ingestion and finish processing all the events in the queue).

🔐 Kafka Kerberos Authentication
Enterprise users can now connect to Kerberos-secured Kafka clusters with full GSSAPI support:
- Kerberos principal configuration - Support for Kerberos authentication with principal and keytab files
- SSL/TLS integration - Kerberos works seamlessly with SSL/TLS for secure connections
- Sidecar gateway - Dedicated Kafka sidecar gateway for handling GSSAPI interactions on the UI
This enhancement enables GlassFlow to work with enterprise Kafka clusters that require Kerberos authentication, expanding compatibility with secure enterprise environments.

🗑️ Dead Letter Queue Enhancements
The Dead Letter Queue (DLQ) has been significantly improved with new management capabilities:
- Flush DLQ endpoint - New API endpoint and UI button to flush DLQ messages
- Sink DLQ support - Sink components now can also write to the DLQ stream.
These improvements give you better control over DLQ management.
🎨 UI/UX Improvements
The user interface has been enhanced with better error handling, notifications, and responsive design:
- Pipeline filtering and sorting - Filter pipelines by health and status, sort by various columns, and view creation timestamps with the new
created_atcolumn - Robust notification system - Improved toast notifications with better styling and positioning
- Standardized error messages - Consistent error messaging throughout the application
- Responsive action buttons - Context menu and inline menu options for different screen sizes
- Portal rendering - Context menus now render in portals for better z-index handling
- Demo mode support - Pipeline action buttons are disabled in demo mode
- Connection edit invalidation - Smart cache invalidation when editing connections
- Topic hydration improvements - Better handling of topic changes and field mapping updates
Pipeline Status Management
Pipeline status management has been streamlined for better control and clarity:
- Consolidated stop and terminate - Simplified pipeline lifecycle management
- Removed pause functionality - Streamlined to active, stopped, and terminated states
- Terminate as kill switch - Terminate now serves as a reliable kill switch for pipelines
- Delete pipeline handling - Pipeline deletion is now properly handled by orchestrators for better resource management
Enhanced Observability
Additional metrics and monitoring capabilities have been added:
- HTTP server metrics - HTTP server metrics are now sent to OpenTelemetry for better API monitoring and observability
- Improved histogram buckets - Fixed bucket boundaries for histograms with
WithExplicitBucketBoundaries - Enhanced metrics visibility - Improved metrics documentation with UI screenshots and detailed information
ClickHouse Column Validation
Better handling and validation of ClickHouse column types:
- Default columns - Improved mapping and validation for default columns
- Materialized columns - Added support for materialized column mappings
- Alias columns - Improved validation for alias column configurations
Bug Fixes
- Fixed topic hydration after editing to enable proper mapping
- Fixed double unlock issue in subscriber stop
- Fixed stream name handling in e2e tests
- Fixed join journey details layout issues
- Fixed table fields loading after topic changes
- Fixed mapping hydration after pipeline edits
- Fixed connection changes persistence
- Fixed deduplication and ClickHouse mapping editing
- Fixed broken links in documentation
- Fixed delay in batch tail synchronization
- Fixed
created_attimestamp preservation when editing pipelines - Fixed Kubernetes CRD spec building duplication
- Fixed observability documentation to highlight gRPC vs HTTP differences
Migration Notes
For Existing Users
- No breaking changes - This release is fully backward compatible
- Editing available - Existing pipelines can now be edited through the UI
- Pause removed - The pause functionality has been removed; use stop/terminate instead
- Pipeline status changes - Stop and terminate have been consolidated for simpler pipeline management
- Kerberos optional - Kerberos authentication is optional and only needed for secured Kafka clusters
Configuration Updates
- Kerberos settings - New connection fields for Kerberos authentication (principal, keytab, etc.)
- DLQ endpoints - New API endpoints for DLQ management operations
- Docker environment variables - Environment variables can now be set for Docker deployments
- HTTP metrics - HTTP server metrics automatically sent to OpenTelemetry when configured
Try It Out
To experience the new features in v2.4.0:
- Deploy the latest version using our Kubernetes Helm charts
- Edit an existing pipeline to see the new editing capabilities in action
- Sort pipelines in the UI by health, status, and creation date
- Configure Kerberos authentication if you’re connecting to secured Kafka clusters
- Explore the improved UI with better notifications and error handling
- Use the DLQ flush feature to manage error messages more effectively
- Explore the API documentation via Swagger for complete endpoint reference
Full Changelog
For a complete list of all changes, improvements, and bug fixes in v2.4.0, see our GitHub release 2.3.0 and GitHub release 2.4.0 .
GlassFlow v2.4.0 continues our commitment to making streaming ETL more flexible, secure, and performant for enterprise production environments.