Redis.
An in-memory store for caching, job queues, rate limits and anything that has to answer in a millisecond.
Talk to us about Redis
Key features
What Redis does well.
Data structures
Hashes, lists, sets and sorted sets are built in, so leaderboards and counters need no extra code.
Streams with consumer groups
Append-only streams with consumer groups let several workers share a queue and acknowledge each message.
Key expiry
Any key can be given a time to live, after which Redis removes it without a clean-up job.
Persistence options
Snapshots and the append-only file write data to disk, so it can be reloaded after a restart.
What we build with it
Fast answers to the questions asked most often.
Redis keeps data in memory, so most reads and writes finish in well under a millisecond. We run it next to the main database, never instead of it: to cache expensive results, hold sessions, run job queues and count requests for rate limits. Valkey, the open-source fork backed by the Linux Foundation, works the same way and is offered by managed services such as Amazon ElastiCache.
Caching
Slow query and API results kept in memory, with expiry times so stale data clears itself.
Background jobs
Queues for emails, exports and imports that run outside the request a person is waiting on.
Rate limits and sessions
Counters and session data shared by every server instance.
When it’s the right choice
Redis fits when the same data is read far more often than it changes, or when several servers need to share short-lived state.
When we’d pick something else
Memory is expensive, and a cache is one more place where data can go stale. We add Redis when measurements show the main database needs help, not by default.
Our Redis services
How we can help.
Caching design
Decisions on what to cache, for how long and how entries are cleared when the source data changes.
Queue set-up
Background job queues with retries and failure handling for emails, imports and exports.
Managed hosting
ElastiCache, Azure Cache or Memorystore configured with replication, persistence and sensible memory limits.
Memory and latency reviews
Checks for large keys, missing expiry times and eviction settings when memory use or latency climbs.
How we work
Starting a Redis project.
Review what exists
Code, data, hosting and the people who maintain it, before any Redis decision is made.
Agree the approach
A written scope: what changes, what stays, the risks and how we will know it worked.
Build in reviewable slices
Working increments your team can test, rather than one large delivery at the end.
Hand over or stay on
Documentation and access for your team, or a defined support scope if you want us to keep going.
Where AI fits
AI in data work.
Vector search where your data lives
PostgreSQL with pgvector (including on Supabase and Neon), MongoDB Atlas and Redis can all store embeddings next to your records, so search does not need a separate system.
Knowledge assistants ↗Access rules before retrieval
Row-level security in PostgreSQL limits what an assistant can retrieve to what the signed-in user is allowed to see.
Knowledge assistants ↗
Where it stops: Embeddings are derived from personal data too, so they need the same retention and deletion rules as the records they came from.
What’s changing
Shifts to plan for.
Dates that affect Redis projects, checked against the official sources.
May 2025
Redis returns to open source
Redis 8 added the AGPLv3 as a licence option, alongside its source-available licences.
Where it fits
Related expertise.
- APIs & integrations Connect your product to the systems your team relies on, with clear contracts and handled failures.
- Cloud architecture Choose and structure cloud services around your product’s data, access and operating needs.
- Monitoring & support Logs, metrics and alerts that show problems early, with agreed support for after launch.
Common questions
Redis questions.
Redis or Valkey?
Both handle the same jobs and speak the same protocol. Redis 8 is available under the AGPLv3 as well as source-available licences, while Valkey uses the BSD licence. We choose based on your hosting and licensing preferences.
What happens if Redis restarts?
For a cache, little: the data is rebuilt from the database. For queues and sessions we turn on persistence or use a managed service with replication, so jobs are not lost.
Further reading
- Firebase, Supabase or a custom back end: how to choose How to choose between Firebase, Supabase and a custom back end by data shape, access rules, cost, exit paths and skills.
- MySQL 8.0 has reached end of life: planning the move to 8.4 What MySQL 8.0’s end of life means, and how to plan, test and roll back an upgrade to MySQL 8.4 LTS.
- Offline-first mobile apps for people who work without signal How to plan a mobile app that keeps working without signal, and what to settle before the first line of sync code.