nix-olde is a tool to show details about outdated packages in your NixOS system using https://repology.org/ database.

It can use both default <nixpkgs> or custom URL or path specified via --nixpkgs / -n parameter.

I usually use the tool to see what I could update in nixpkgs that my system currently uses.

At runtime nix-olde uses 2 external packages and expects them in PATH:

• curl to fetch repology.org reports
• nix to query locally installed and available packages

To build nix-olde you will need rustc and cargo. Cargo.tml contains more detailed description of dependencies.

There is no Cargo.lock package or uploaded crate just yet. I'm not sure if such a small tool warrants it. Thus you need to clone and build it using cargo build tool:

$ git clone https://github.com/trofi/nix-olde.git
$ cd nix-olde
$ cargo build

Now you should be ready to run it.

Diff against current system:

$ ./target/debug/nix-olde

Diff against latest staging:

$ ./target/debug/nix-olde -n https://github.com/NixOS/nixpkgs/archive/refs/heads/staging.tar.gz

Or against local checkout:

$ ./target/debug/nix-olde -n ./nixpkgs

I usually use small shell wrapper to build-and-run against local staging checkout:

$ ./mkrun.bash -n $(realpath ~/n)

$ cargo build && target/debug/nix-olde
...
Fetching 'repology'
Fetching 'available'
Fetching 'installed'
'installed' done, took 6.10 s.
'available' done, took 12.22 s.
'repology' done, took 75.38 s.

repology a52dec "0.8.0" | nixpkgs {"0.7.4"} {"nixos.a52dec"}
repology alsa-lib "1.2.8" | nixpkgs {"1.2.7.2"} {"nixos.alsa-lib"}
repology alsa-ucm-conf "1.2.8" | nixpkgs {"1.2.7.1"} {"nixos.alsa-ucm-conf"}
repology appstream "0.15.6" | nixpkgs {"0.15.5"} {"nixos.appstream"}
repology atomicparsley "20221229" | nixpkgs {"20210715.151551.e7ad03a"} {"nixos.atomicparsley"}
repology audit "3.0.9" | nixpkgs {"2.8.5"} {"nixos.audit"}
repology autogen "5.19.96" | nixpkgs {"5.18.16"} {"nixos.autogen"}
...
repology xrandr "1.5.2" | nixpkgs {"1.5.1"} {"nixos.xorg.xrandr"}
repology xset "1.2.5" | nixpkgs {"1.2.4"} {"nixos.xorg.xset"}
repology xsetroot "1.1.3" | nixpkgs {"1.1.2"} {"nixos.xorg.xsetroot"}
repology xterm "378" | nixpkgs {"377"} {"nixos.xterm"}
repology xz "5.4.1" | nixpkgs {"5.4.0"} {"nixos.xz"}
repology zxing-cpp-nu-book "2.0.0" | nixpkgs {"1.4.0"} {"nixos.zxing-cpp"}

388 of 1518 (25.56%) installed packages are outdated according to https://repology.org.

Some installed packages are missing in available list: 68
  Add '--verbose' to get it's full list.

There are a few options:

$ ./mkrun.bash --help

A tool to show outdated packages in current system according to repology.org database

Usage: nix-olde [OPTIONS]

Options:
  -n, --nixpkgs <NIXPKGS>  Alternative path to <nixpkgs> location
  -v, --verbose            Enable extra verbosity to report unexpected events, fetch progress and so on
  -h, --help               Print help
  -V, --version            Print version

--nixpkgs / -n is most useful when you are looking for packages that were not yet updated in a particular development branch of nixpkgs repository (usually staging or master).

The theory is simple: fetch data from various data sources and join them together. Each data source returns a tuple of package name, package version and possibly a bit of metadata around it (name in other systems, possible status).

Currently used data sources are:

• installed packages: uses nix-instantiate / nix show-derivation. Provides fields:
  • name (example: python3.10-networkx-2.8.6)
  • version (example: 2.8.6)
• available packages: uses nix-env -qa --json tool, memory hungry. Provides fields:
  • [keyed from installed packages] name (example: python3.10-networkx-2.8.6)
  • attribute: nixpkgs attribute path (example: nixos.python310Packages.networkx)
  • pname: name with version component dropped (example: nixos.python310Packages.networkx)
  • version (example: 2.8.6)
• https://repology.org/ json database: uses https://repology.org/api/v1/projects/ HTTP endpoint. Provides fields:
  • repo: package repository (example: "nix_unstable")
  • [keyed from available] name: with version component dropped (example: nixos.python310Packages.networkx).
  • version (example: 2.8.6)
  • status: package status in repository (examples: "newest", "outdared").

nix-olde is distributed under MIT license.