Hazelcast vs Redis: What are the differences?

Hazelcast: Clustering and highly scalable data distribution platform for Java. With its various distributed data structures, distributed caching capabilities, elastic nature, memcache support, integration with Spring and Hibernate and more importantly with so many happy users, Hazelcast is feature-rich, enterprise-ready and developer-friendly in-memory data grid solution; Redis: An in-memory database that persists on disk. Redis is an open source, BSD licensed, advanced key-value store. It is often referred to as a data structure server since keys can contain strings, hashes, lists, sets and sorted sets.

Hazelcast and Redis belong to "In-Memory Databases" category of the tech stack.

"High Availibility" is the primary reason why developers consider Hazelcast over the competitors, whereas "Performance" was stated as the key factor in picking Redis.

Hazelcast and Redis are both open source tools. Redis with 37.1K GitHub stars and 14.3K forks on GitHub appears to be more popular than Hazelcast with 3.15K GitHub stars and 1.15K GitHub forks.

reddit, Instacart, and Slack are some of the popular companies that use Redis, whereas Hazelcast is used by Yammer, Seat Pagine Gialle, and Stormpath. Redis has a broader approval, being mentioned in 3239 company stacks & 1732 developers stacks; compared to Hazelcast, which is listed in 25 company stacks and 15 developer stacks.