Alternatives to Nix
Functional package manager with reproducible builds and atomic rollbacks. The listings below can replace it for an important use case. Each note says what changes if you switch.
The original
Nix
Functional package manager with reproducible builds and atomic rollbacks.
Replacements
Listings that take over the same core job as Nix.
GNU Guix
A transactional package manager and GNU/Linux distribution whose packages and system configurations are written in Guile Scheme.
GNU Guix offers similar reproducible environments and per-user packages, but configuration is written in Guile Scheme and only free software is packaged, and it runs on Linux only.
Homebrew
Package manager for macOS and Linux with formulae and GUI app casks.
Homebrew is a conventional package manager for macOS and Linux with prebuilt bottles and Mac app casks, without Nix's reproducible builds or atomic rollbacks.
Also worth comparing
These listings name Nix as their own alternative, so the relationship runs both ways.
Flatpak
Sandboxed application packaging for Linux, with shared runtimes and Flathub.
Nix is a functional package manager for Linux and macOS with reproducible builds and atomic rollbacks, at the cost of a steep learning curve.
Snap
Canonical's universal Linux packages with confinement and automatic updates.
Nix offers reproducible builds and atomic rollbacks on Linux and macOS, but its language has a steep learning curve and the store needs garbage collection.
Similar software
Related functionality, not a direct replacement.