Cachix

What Cachix is

Cachix hosts Nix binary caches so binaries can be shared across continuous integration, development, and deployment environments. Its CLI can push binaries, watch a Nix store, and configure Nix to use a cache. The service says its cache optimizations speed up binary cache roundtrips, while Cloudflare CDN caching provides performance and unlimited bandwidth on all plans.

Teams can grant members read or write access to a cache and revoke access tokens. Private cache reads and writes require a token, and binary cache entries are signed with either a managed or self-signed key. If a cache fills its storage, Cachix removes least recently used entries and sends a warning email when usage reaches 85% of the limit.

Cachix documents CI guides for GitHub Actions, Buildkite, CircleCI, GitLab CI, Hercules CI, Hydra, and Travis CI. Its Deploy service continuously deploys to Nix profiles including NixOS, nix-darwin, and Home Manager through a pull model. Enterprise options include on-premise or self-hosted deployment, SSO, SLA, dedicated premium support, custom deployment, and audit logs. Cachix was launched in 2018 by Enlambda OÜ and is headquartered in Kuusalu vald, Estonia. It offers a free plan and a 14-day trial.

Who it suits

Cachix suits teams that use Nix and need to share binary caches across CI, development, and deployment. It also fits teams that want controlled cache access, documented CI integrations, or continuous deployment to Nix profiles.

Limits

The listed Starter plan includes 50 GiB of storage; least recently used entries are removed when a cache reaches its storage limit. The listed Starter, Standard, and Pro plans require contacting Cachix for pricing.

Getting started

1. Open the Cachix website.
2. Choose the free plan or start the 14-day trial.
3. Use the Cachix CLI to configure Nix to use a cache.
4. Push binaries or watch a Nix store with the CLI.
5. Connect a CI workflow using one of the documented guides.

Verdict

Choose Cachix if your team uses Nix and needs shared binary caches with CLI management, CI guides, and deployment support. Look elsewhere if you need a plan price upfront or storage beyond the listed Starter allowance without moving to another plan.