Kestrel is a simple, distributed message queue system built originally by Twitter. Its design is relatively lightweight and is engineered for speed and simplicity. Kestrel supports queuing patterns such as enqueue, dequeue, and delayed re-enqueue (for example, when a consumer fails to process a message). It stores messages persistently on disk with a memory-backed cache, allowing recovery in case of failures. Because it is intended for relatively simple use cases, it does not provide the full feature set of some enterprise messaging systems, but is often sufficient for many asynchronous or buffered workloads. Over time, the project became inactive and is now archived. Its minimalism and ease of integration made it appealing for smaller or more controlled message-queueing needs.

Features

  • Implements durable (journaled) queues so that messages are preserved even in case of failures
  • Supports multiple protocols (memcache protocol and thrift protocol) for compatibility and flexibility
  • Item expiration (messages can be automatically expired after time)
  • Fan-out queues: one writer, many readers, to broadcast messages to several consumers
  • Ordered queue semantics (messages delivered in insertion or defined ordering)
  • Simple, lightweight, designed for performance and reliability in message queue use-cases

Project Samples

Project Activity

See All Activity >

Categories

Messaging

License

MIT License

Follow Kestrel

Kestrel Web Site

Other Useful Business Software
Full-stack observability with actually useful AI | Grafana Cloud Icon
Full-stack observability with actually useful AI | Grafana Cloud

Our generous forever free tier includes the full platform, including the AI Assistant, for 3 users with 10k metrics, 50GB logs, and 50GB traces.

Built on open standards like Prometheus and OpenTelemetry, Grafana Cloud includes Kubernetes Monitoring, Application Observability, Incident Response, plus the AI-powered Grafana Assistant. Get started with our generous free tier today.
Create free account
Rate This Project
Login To Rate This Project

User Reviews

Be the first to post a review of Kestrel!

Additional Project Details

Operating Systems

Linux, Mac, Windows

Programming Language

Scala

Related Categories

Scala Messaging Platform

Registered

2025-09-18