Redis 7 shipped in April 2022 with solid improvements: multi-part AOF for persistence, better Lua scripting, and cluster-aware command specs. But what I find more interesting is what the release tells us about where Redis sits as critical infrastructure and how the in-memory data structure landscape is evolving.
Redis as foundational infrastructure
Redis is used as cache, session store, message broker, leaderboard, rate limiter, and distributed lock, often simultaneously in the same application. Its single-threaded event loop with O(1) and O(log n) operations for most data structures makes it predictably fast. The 7.0 release focuses on operational improvements rather than new data structures: better persistence, better scripting, and better cluster tooling.
Caching patterns in .NET
The IDistributedCache interface in ASP.NET Core provides a consistent API for Redis, SQL Server, and NCache. The recommended caching patterns: cache-aside (check cache, get from database on miss, populate cache), write-through (write to cache and database simultaneously), and read-through (cache transparently fetches from database on miss). The cache-aside pattern is most common in .NET applications using IDistributedCache.
Redis Cluster vs standalone
Redis Cluster provides horizontal partitioning and automatic failover. For most applications, a single Redis replica set (primary with replicas) provides sufficient throughput and the replication latency of 1-5ms is acceptable. Cluster is necessary when a single node's memory is insufficient for the data set, or when write throughput exceeds what a single node can handle. Most enterprise applications reach Redis Cluster requirements at hundreds of millions of operations per day.
The Redis licence question
Redis's core data structures are under the BSD licence. Redis Stack modules (search, JSON, time series, bloom filters) were moved to non-open-source licences in 2022. This is the precedent for the HashiCorp BSL change in 2023. Valkey, the Linux Foundation fork of Redis, was created in 2024 in response to Redis Ltd's licence change. The open source core remains available; the question is where the ecosystem investment goes.