redis4cats

redis4cats
==========

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Redis client built on top of [Cats Effect](https://typelevel.org/cats-effect/), [Fs2](http://fs2.io/) and the async Java client [Lettuce](https://lettuce.io/).

### Quick Start

```scala
import cats.effect.*
import cats.implicits.*
import dev.profunktor.redis4cats.Redis
import dev.profunktor.redis4cats.effect.Log.Stdout.given

object QuickStart extends IOApp.Simple:

  val run: IO[Unit] =
    Redis[IO].utf8("redis://localhost").use: redis =>
      for
        _ <- redis.set("foo", "123")
        x <- redis.get("foo")
        _ <- redis.setNx("foo", "should not happen")
        y <- redis.get("foo")
        _ <- IO(assert(x === y))
      yield ()
```

The API is quite stable and *heavily used in production*. However, binary compatibility is not guaranteed across versions for now.

If you like it, give it a ⭐ ! If you think we could do better, please [let us know](https://gitter.im/profunktor-dev/redis4cats)!

### Versions

The `1.x.x` series is built on Cats Effect 3 whereas the `0.x.x` series is built on Cats Effect 2.

redis4cats is a thin wrapper over the async Java client [Lettuce](https://lettuce.io/), so each series tracks a
particular Lettuce major version:

| redis4cats | Lettuce                   | Cats Effect |
| ---------- | ------------------------- | ----------- |
| `3.x`      | `7.x`                     | `3.x`       |
| `2.x`      | `6.x` (currently `6.8.x`) | `3.x`       |
| `1.x`      | `6.x` (`6.1.x`–`6.5.x`)   | `3.x`       |
| `0.x`      | `5.3.x` then `6.0.x`      | `2.x`       |

### Dependencies

Add this to your `build.sbt` for the [Effects API](https://redis4cats.profunktor.dev/effects/) (depends on `cats-effect`):

```
libraryDependencies += "dev.profunktor" %% "redis4cats-effects" % Version
```

Add this for the [Stre