> For the complete documentation index, see [llms.txt](https://tarmac.gitbook.io/tarmac-framework/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://tarmac.gitbook.io/tarmac-framework/running-tarmac/datastores/kvstore.md).

# Key:Value

Selecting a KV Store

Tarmac has support for multiple Key:Value datastore storage systems. These datastores can change with basic configuration options within Tarmac. As a WASM Function developer, you do not need to know the underlying datastore when writing the function. Callbacks for accessing the Key:Value datastore are generic across all supported datastores.

To start using a Key:Value datastore, set the `enable_kvstore` configuration to `true` and specify which supported platform to use with the `kvstore_type` variable.

The below table outlines the different available options.

| Datastore | Type option | Description                                          | Useful for                                                        |
| --------- | ----------- | ---------------------------------------------------- | ----------------------------------------------------------------- |
| In-Memory | `in-memory` | In-Memory key/value store                            | Testing, Development, Non-Persistent Caching                      |
| BoltDB    | `boltdb`    | BoltDB Embedded key/value store                      | Strong Consistency, Persistent Storage                            |
| Redis     | `redis`     | Redis including Sentinel and Enterprise capabilities | Strong Consistency, Fast Reads and Writes, Non-Persistent storage |
| Cassandra | `cassandra` | Cassandra including TLS connectivity                 | Eventual Consistency, Persistent Storage, Large sets of data      |
| NATS      | `nats`      | NATS JetStream key/value store                       | Distributed, Cloud-native, Persistent Storage                     |

For more detailed configuration options, check out the [Configuration](/tarmac-framework/running-tarmac/configuration.md) documentation.