Databases & Storage
Often the solution to persistent data storage is to connect your Fly App to a separate database or object store.
Fly.io offers a deploy-it-yourself Postgres app with some tools to make it easier to manage yourself.
Explore these, and further options, for data storage in the following sections.
Anything an App VM writes to its root disk is ephemeral: when the VM is redeployed, the root file system is rebuilt using its Docker image, deleting any data written to it since it was started up. This is fine for
/tmp files, but most apps need to keep state in a database or another form of persistent storage.
- Fly Volumes - Persistent storage on Fly.io is provided by Fly Volumes. You can use Volumes on an App directly, or run a separate database App with Volume storage and connect an App to that. A Fly Volume is a slice of NVMe disk storage attached to the server that hosts your Machine. Volumes have pros and cons, and you should read up on Fly Volumes before deciding whether they’re the best solution for your use case.
These are projects that we develop and support. They’re not managed services; you can deploy them yourself as Fly Apps.
- Fly Postgres - PostgreSQL is a popular relational database. When you deploy an App on Fly.io, we give you the option to launch a Fly Postgres App and attach it to your App. We provide tools for deployment and management; you manage the cluster once it’s deployed.
- LiteFS for SQLite - SQLite is a very lightweight file-based database. LiteFS is a distributed file system that transparently replicates SQLite databases. You deploy it and you manage it.
- Redis by Upstash - Redis is an in-memory database commonly used for caching. A managed service by Upstash.
If your application calls for a different solution, you can deploy it yourself as an App on Fly.io. These examples can help you get started with other popular storage options.
If you want a fully managed database or storage solution for your Fly Apps, there are many great options, including:
- Crunchy Bridge Managed Postgres (on AWS, Azure, GCP, or Heroku)
- Neon Serverless Postgres
- PlanetScale Serverless MySQL (guide to use with Fly Apps)
- Supabase Postgres
- MinIO Hosted Object Storage
- Fauna (guide to use with Fly Apps)
You can connect your Fly Apps to the usual suspects, too: