Cachix vs clcache

Cachix hosts Nix binary caches so teams can share binaries across CI, development, and deployment environments. Its CLI can push binaries, watch a Nix store, and configure Nix to use a cache. The service says its optimizations speed up cache roundtrips, while Cloudflare CDN provides performance and unlimited bandwidth on all plans. When a cache reaches its storage limit, least-recently-used entries are removed; Cachix says it sends a warning email at 85% of that limit. Documentation includes CI guides for GitHub Actions, Buildkite, CircleCI, GitLab CI, Hercules CI, Hydra, and Travis CI. Cachix Deploy uses a pull model to deploy continuously to Nix profiles such as NixOS, nix-darwin, and Home Manager. Teams can assign read or write access, revoke tokens, and require a token for private cache reads and writes; cache entries are signed. Enterprise options include on-premise or self-hosted deployment, SSO, SLA, dedicated premium support, custom deployment, and audit logs. Cachix offers a free plan and a 14-day trial. Listed Starter, Standard, and Pro plans have prices available by contacting Cachix.

clcache is a free, open-source Python script for Windows builds using Microsoft Visual C++ cl.exe. It intercepts compiler calls and reuses cached object files to avoid recompiling matching work, while unsupported invocations can be passed to the real compiler. Cache keys use preprocessed source, a normalized command line, and the compiler binary’s size and modification time. Command-line controls provide statistics, cleanup, clearing, and maximum-size settings; the default limit is 1073741824 bytes (1 GiB). Object files can be compressed at levels 1 through 9, though changing compression settings requires clearing the cache. Hard-link mode requires cache and build directories on the same drive. Documentation covers Visual Studio and MSBuild integration, recommends disabling TrackFileAccess, and describes optional hash caching and memcached storage. The documented path requires /c, excludes /link and /Zi, and supports /Z7. INCLUDE and LIBPATH changes may not be detected.