Cachely vs Harmonia

Cachely is a managed remote build cache for Nx, Lerna, Turborepo, Gradle, and Bazel. It shares build artifacts between CI runners and developer machines so supported tasks can reuse outputs. Cachely works through the listed remote-cache protocols and supports GitHub Actions, GitLab CI, CircleCI, Jenkins, Buildkite, Woodpecker, Drone, and self-hosted runners. Its dashboard reports cache hit rate, slow tasks, and estimated CI time and cost savings. Setup involves creating a workspace, generating a token, and configuring the build tool; the maker says this takes about five minutes. Tokens are hashed with SHA-256, scoped to one workspace, revocable, and fixed as read-only or read-write. Artifacts are immutable, content-addressed, served over HTTPS from Cloudflare R2, encrypted at rest, and removed after 20 days. Cachely has a free plan with 1 GiB storage and 500K monthly requests. Team costs $29.99 a month or $24.99 a month billed yearly. Enterprise pricing is custom.

Harmonia is free, open-source software for serving a Nix store as a binary cache over HTTP. Written in Rust for Linux self-hosting, it supports HTTP range requests for NAR streaming and streaming build logs. The /serve// endpoint can provide package contents and discover index.html to serve websites directly from the Nix store. Harmonia can transparently compress content with zstd and provide TLS when no frontend web server is used. Documentation covers a NixOS module and nginx HTTPS frontend configuration for a public cache. Narinfo signing is disabled unless private signing-key paths are supplied. Prometheus metrics are available at /metrics, with a Grafana dashboard included in the repository. Since version 3.1.0, metadata is read directly from db.sqlite without a nix-daemon connection. Version 3.3.0 adds harmonia-gc for removing store garbage while nix-daemon builds. It uses the MIT License.