Simple HTTP API
Works with any programming language that supports JSON and HTTP.
Produce Messages
Add work to your queue with a simple HTTP request
curl -X POST localhost: 2319/v1/queue.produce \
-H "Content-Type: application/json" \
-d '{
"queue_name": "email-queue",
"items": [{
"kind": "welcome-email",
"reference": "user-123",
"utf8": "{\"email\": \"user@example.com\"}"
}]
}'What is Querator?
Querator combines almost-exactly-once delivery with the simplicity of HTTP. Messages are leased to consumers – ensuring your message is never lost even when consumers crash. Unlike many message brokers that require complex management and esoteric protocols, Querator works withany programming language that supports JSON and HTTP.
Built for scale from day one, Querator features automatic partition balancing – no manual partition assignment needed. The server intelligently distributes your workload while you focus on your business logic. With support for both JSON andhigh-performance Protobuf, you get the flexibility to optimize for readability or performance as your needs evolve.
What makes Querator truly different is its database-first approach. Instead of managing another piece of infrastructure, Querator leverages thedatabases you already operate – PostgreSQL, MySQL, or MongoDB. This means familiar backup strategies, monitoring tools, and operational procedures.Your existing expertise becomes your queue management expertise.
Use Cases
Background Jobs
Email notifications, report generation, AI Training Jobs
Event Processing
User analytics, audit logs, webhook delivery
Distributed Workflows
Order processing, ETL pipelines, media transcoding
Microservice Communication
Async commands, event sourcing, saga patterns
Almost Exactly Once?
We say "Almost" Exactly Once because Exactly Once Delivery (EOD) is theoretically impossible. However, in practice, you can achieve AEODwhich is functionally equivalent to EOD, with the understanding that occasional duplicate deliveries may occur due to system failures.
From our experience with EOD systems at scale, the likelihood of Duplicate Delivery and processing is about the same as your system's overall failure rate. In other words, message delivery is only as reliable as the system it runs on.
Anyone claiming their system provides precise Exactly Once Delivery is being disingenuous at best.
Architecture Overview
Querator enables API users to interact with queues where each queue can consist of one or more partitions. Each partition is backed by a single table in the database.
Clients
Querator
Partition Balancing
Lease Management
Database
Open Source
Querator is open source and community-driven. Whether you're fixing bugs, adding features, or sharing ideas, every contribution makes queuing better for everyone.