---
title: Remote cache
description: Choose a backend and share compiler outputs between machines
---
A remote lets one machine reuse compatible outputs another has published.
Kache checks the local store first. After a local miss, the daemon can download
an exact matching entry; it uploads new entries in the background.
You do not need a remote for local builds or reuse between worktrees on one machine.
## Choose a backend
| You already have… | Use | Setup |
| --- | --- | --- |
| An S3-compatible bucket, including AWS S3, R2, or MinIO | `s3` | [S3 setup](/docs/remote-cache/s3-setup) |
| A Google Cloud Storage bucket | `gcs` | [GCS setup](/docs/remote-cache/gcs-setup) |
| A directory mounted on each machine | `filesystem` | [Filesystem setup](/docs/remote-cache/filesystem-setup) |
| An OCI registry such as GHCR | `oci` | [OCI setup](/docs/remote-cache/oci-setup) |
Follow the selected guide to configure `[cache.remote]` and credentials, then run:
```bash
kache doctor
cargo build --locked
kache daemon stop
```
`doctor` shows the remote and checks that it answers a read. It never tries a
write, and on S3 a read that the bucket policy refuses counts as a miss, so a
passing check does not prove that a job can publish.
The build uses the daemon for remote lookups and background uploads.
`daemon stop` gives queued uploads up to 30 seconds before the daemon exits,
which matters on an ephemeral runner.
[CI setup](/docs/remote-cache/ci#other-ci-systems) covers what happens to the
rest.
## Control who publishes
Use [CI setup](/docs/remote-cache/ci) for write policy and credential examples.
On GitHub Actions and GitLab CI, remote writes normally require a push to a
protected branch. An optional pull-request prefix permits isolated writes on
supported backends. OCI pull requests remain read-only because registry tag
prefixes cannot isolate write permissions.
A remote contains compiler outputs. Only give write access to jobs and people
you trust to produce those outputs.
## Manage an existing remote
- [Sync](/docs/remote-cache/sync) explains explicit pulls and pushes without the daemon.
- [Bounding storage](/docs/remote-cache/bounding) covers retention outside the local store.
- [Configuration](/docs/getting-started/configuration#remote-settings) lists settings and defaults.
- [Daemon lifecycle](/docs/daemon/lifecycle) explains services, credentials, and config changes.
The optional [planner service](/docs/remote-service) ranks entries for prefetch.
Start with a storage backend; exact-key lookups work without that service.