Redis vs NATS | Unicorn Factories

Overview

Redis Streams and NATS Streaming (now superseded by JetStream) are both lightweight alternatives to Apache Kafka for message streaming. They target similar use cases but with different architectural philosophies.

Feature Comparison

Capability	Redis Streams	NATS JetStream
Architecture	In-memory with persistence options	Pure streaming platform, purpose-built
Throughput	100K-1M msg/sec	1M+ msg/sec per server
Latency	Sub-millisecond	Sub-millisecond
Delivery Guarantees	At-least-once, exactly-once with Lua	At-least-once, exactly-once
Persistence	RDB/AOF optional	Core feature, not optional
Replication	Redis Cluster, Sentinel	Built-in clustering
Multi-tenancy	Database numbers (limited)	Streams, consumers, limits
Resource Usage	Higher (in-memory)	Lower (file-based)

When to Choose Redis Streams

Existing Redis infrastructure: Already using Redis for caching/sessions
Hybrid workloads: Need both data structures and streaming
Complex data operations: Lua scripting, transactions needed
Time-series patterns: Sorted sets + Streams combination

When to Choose NATS JetStream

Pure messaging focus: Don't need data structures
Lower resource footprint: Edge devices with limited RAM
Simpler operations: Purpose-built for streaming, less tuning
Multi-tenancy needs: Better isolation between streams

Key Differences

Redis is a data store that happens to do streaming well. NATS is a messaging system that happens to persist messages. This fundamental difference drives most architectural decisions.

Can They Coexist?

Less common than Redis+Kafka, but possible: Redis for hot data and complex operations, NATS for high-throughput messaging backbone.