# atmos ci cache

Reduce repeated downloads and setup work in CI by reusing installed tools and other cached artifacts
between runs. Atmos restores and saves the configured cache through the CI provider.

> ⚠️ Experimental

**Configure the CI Cache**

Learn how to enable the cache, choose automatic vs. manual behavior, and customize the cache key, paths, and restore-keys in your `atmos.yaml`.

CI Cache Configuration Reference[Read more](/cli/configuration/ci/cache)

## Lifecycle

The cache includes the toolchain install path and other files under the Atmos cache root. Atmos uses the active CI provider's cache store—the same store used by `actions/cache` on GitHub Actions.

The cache lifecycle can run **in a single Atmos invocation** (automatic restore-on-start and save-on-end) or be **spread across CI steps** with the explicit subcommands:

**File:** `Spread across steps`

```
- run: atmos ci cache restore   # step 1: warm the cache
- run: atmos toolchain install  # step 2: use it (installs only what's missing)
- run: atmos ci cache save      # step 3: persist it for the next run
```

Both styles share one implementation. "Automatic" is just the same idempotent operations invoked by the process lifecycle, so manual and automatic invocations never double-execute (cache entries are write-once; an exact-key hit at restore time skips the save).

## Requirements

Saving and restoring content require running inside a supported CI provider (GitHub Actions today), which exposes the runtime cache credentials. Outside CI, these commands report that the cache is unavailable. The cache must also be enabled — see the [configuration reference](/cli/configuration/ci/cache).

## Subcommands

## Related

- [CI Cache Configuration](/cli/configuration/ci/cache) - Configure the cache in `atmos.yaml`
- [CI Configuration](/cli/configuration/ci) - Configure CI integration
- [`atmos toolchain`](/cli/commands/toolchain/usage) - Manage the toolchain that the cache warm-starts