nixpkgs and repology changes
Tl;DR: nixpkgs changed the way it exports data to repology and many packages need fixing
In nixpkgs/451424 nixpkgs
changed substantially how it exports data about available packages.
As a result some packages like flare stopped being reported to repology.org
correctly. Luckily the fix is to usually use pname / version instead of
direct name. Example fix
for flare package:
--- a/pkgs/by-name/fl/flare/package.nix
+++ b/pkgs/by-name/fl/flare/package.nix
@@ -6,7 +6,8 @@
}:
buildEnv {
- name = "flare-1.14";
+ pname = "flare";
+ version = "1.14";
paths = [
(callPackage ./engine.nix { })The bug
I happen to maintain nix-olde program.
It’s a tool to show you what outdated packages your system has installed.
The tool is hacky: both in a way how it looks up what you have installed
in the system and in how it maps that information to repology.org database.
It errs on the side to not print possibly wrong or missing information.
A few days ago I casually ran nix-olde against my system and got very
odd outputs, like:
repology r:clock "0.7.4" | nixpkgs {"0.8.4"} {"haskellPackages.clock"}
repology r:digest "0.6.39" | nixpkgs {"0.0.2.1"} {"haskellPackages.digest"}
repology r:hedgehog "0.2" | nixpkgs {"1.5"} {"haskellPackages.hedgehog"}
repology r:mmap "0.6-23" | nixpkgs {"0.5.9"} {"haskellPackages.mmap"}
repology r:warp "0.2.3" | nixpkgs {"3.4.9"} {"haskellPackages.warp"}
repology r:yaml "2.3.12" | nixpkgs {"0.11.11.2"} {"haskellPackages.yaml"}Here nix-olde says that it compared R language packages against
Haskell language packages and was unhappy about version mismatch. That
looked very wrong. Turns out that repology.org changed the way it
reports nixpkgs packages for nixpkgs_unstable repository.
Before the change repology reported the following package descriptions:
"python:networkx": [
{
"repo": "nixpkgs_unstable",
"srcname": "python310Packages.networkx",
"visiblenamename": "python3.10-networkx",
"version": "2.8.6",
"status": "outdated",
},
]After the change it started producing the following output:
"python:networkx": [
{
"repo": "nixpkgs_unstable",
"srcname": "python310Packages.networkx",
"visiblename": "networkx",
"version": "2.8.6",
"status": "outdated",
},
]nix-olde used to rely on visiblename: it was conveniently not too
specific (did not contain a version) and yet was specific enough to contain
package ecosystem prefix. But now visiblename omits ecosystem entirely.
This caused all the problematic reports.
I fixed it with this commit.
How does nixpkgs export data to repology?
repology.org is configured to fetch package lists from nixpkgs
here:
- name: nix_unstable
type: repository
desc: nixpkgs unstable
statsgroup: nix
family: nix
ruleset: [nix, nix_name]
color: '7eb2dd'
minpackages: 120000
default_maintainer: fallback-mnt-nix@repology
sources:
- name: packages-unstable.json
fetcher:
class: FileFetcher
url: https://channels.nixos.org/nixos-unstable/packages.json.br
parser:
class: NixJsonParser
use_pname: trueNote that it was changed
very recently to enable use_pname.
nixpkgs on its side generates packages.json.br with an equivalent of
this:
NIX_STATE_DIR=$TMPDIR NIX_PATH= nix-instantiate --eval --raw --expr "import $src/pkgs/top-level/packages-info.nix {}" | sed "s|$src/||g" | jq -c > packages.json
brotli -9 < packages.json > packages.json.brNote that this also
changed recently.
Before the change the code used to use nix-env:
(
echo -n '{"version":2,"packages":'
NIX_STATE_DIR=$TMPDIR NIX_PATH= nix-env -f $src -qa --meta --json --show-trace --arg config 'import ${./packages-config.nix}'
echo -n '}'
) | sed "s|$src/||g" | jq -c > packages.json
brotli -9 < packages.json > packages.json.brIs there a difference introduced?
Why does it matter? Conveniently currently only nixpkgs_unstable has
the change. Previous releases like nixos-25.11 still use the previous
mechanism. Let’s compare the outputs of python3Packages.networkx:
$ curl -L https://channels.nixos.org/nixos-unstable/packages.json.br > unstable-packages.json.br
$ brotli -d <unstable-packages.json.br | jq '.packages."python313Packages.networkx"|[.name, .pname, .version]'
[
"python3.13-networkx-3.5",
"networkx",
"3.5"
]
$ curl -L https://channels.nixos.org/nixos-25.11/packages.json.br > 25.11-packages.json.br
$ brotli -d <25.11-packages.json.br | jq '.packages."python313Packages.networkx"|[.name, .pname, .version]'
[
"python3.13-networkx-3.5",
"python3.13-networkx",
"3.5"
]Here we see that pname changed from python3.13-networkx to networkx.
For this package it’s a reasonable change. Let’s look at flare instead:
$ brotli -d <unstable-packages.json.br | jq '.packages.flare|[.name, .pname, .version]'
[
"flare-1.14",
"flare-1.14",
""
]
$ brotli -d <25.11-packages.json.br | jq '.packages.flare|[.name, .pname, .version]'
[
"flare-1.14",
"flare",
"1.14"
]Here the change effectively broke both package name and version reporting
in unstable. As a result flare-rpg is missing an unstable entry on
repology:
nixpkgs stable 23.11 flare 1.14
nixpkgs stable 24.05 flare 1.14
nixpkgs stable 24.11 flare 1.14
nixpkgs stable 25.05 flare 1.14
nixpkgs stable 25.11 flare 1.14Normally unstable entry looks like
this:
nixpkgs stable 23.11 re2c 3.1
nixpkgs stable 24.05 re2c 3.1
nixpkgs stable 24.11 re2c 3.1
nixpkgs stable 25.05 re2c 4.1
nixpkgs stable 25.11 re2c 4.3.1
nixpkgs unstable re2c 4.4Why does it happen?
Before the nixpkgs/451424
change the split from "flare-1.14" down to "flare" "1.14" was done
by nix-env -qa itself! It does not have any advanced heuristics. I
noticed it before when I just started on nix-olde.
For example in
nix/7540 nix splits
"font-adobe-75dpi-1.0.3" in an unexpected way:
$ nix-env -f. -qa --json | fgrep -A9 xorg.fontadobe75dpi
"xorg.fontadobe75dpi": {
"name": "font-adobe-75dpi-1.0.3",
"outputName": "out",
"outputs": {
"out": null
},
"pname": "font-adobe",
"system": "x86_64-linux",
"version": "75dpi-1.0.3"
},It’s "font-adobe" "75dpi-1.0.3". But it should have been
"font-adobe-75dpi" "1.0.3" instead!
Normally all 3 name / pname / version come directly from the attributes
of a package:
$ nix repl -f '<nixpkgs>'
nix-repl> with re2c; [ name pname version ]
[
"re2c-4.4"
"re2c"
"4.4"
]For some packages not all of them are defined:
nix-repl> with flare; [ name pname version ]
[
"flare-1.14"
«error: undefined variable 'pname'»
«error: undefined variable 'version'»
]The fix is usually simple: instead of defining name directly use
pname / version split. For example:
--- a/pkgs/by-name/fl/flare/package.nix
+++ b/pkgs/by-name/fl/flare/package.nix
@@ -6,7 +6,8 @@
}:
buildEnv {
- name = "flare-1.14";
+ pname = "flare";
+ version = "1.14";
paths = [
(callPackage ./engine.nix { })How does repology handle such packages?
Does repology do anything special about these "version": "" cases?
repology-updater/repology/parsers/parsers/nix.py handles versions
somewhere here.
It already has to work around cases of wrong version splits:
for verprefix in ['100dpi', '75dpi']:
if packagedata['version'].startswith(verprefix):
pkg.log('dropping "{}", "{}" does not belong to version'.format(packagedata['name'], verprefix), severity=Logger.ERROR)
skip = True
breakOtherwise, "version" is extracted
as is:
pname = packagedata['pname']
version = packagedata['version']
# This is temporary solution (see #854) which overrides pname and version with ones
# (ambigiously) parsed from name. That's what nix currently does (instead of exposing
# explicitly set pname and version), and we do the same instead of using pname/version
# provided by them to avoid unexpected change in data when/if they change their logic
# As soon as they do and changed data is verified, this block may be removed
match = re.match('(.+?)-([0-9].*)$', packagedata['name'])
if match is None:
pkg.log('cannot parse name "{}"'.format(packagedata['name']), severity=Logger.ERROR)
continue
elif not self._use_pname:
pname = match.group(1)
version = match.group(2)Thus, _use_pname (enabled in nixpkgs_unstable) effectively disables name version
heuristics.
Are there any more affected packages?
I wondered now many more packages in packages.json that do have
version in pname with a version specified, but lack name form:
$ brotli -d <unstable-packages.json.br | fgrep -B4 '"version": ""' d | fgrep pname | sort -u | grep -P -- '-[0-9]+(\.[0-9]+)*\"' | wc -l
260Here I filtered only pname that seemingly look like a version. I probably
missed a few complicated cases. But it’s a good first pass. Here are
package examples:
$ brotli -d <unstable-packages.json.br | fgrep -B4 '"version": ""' d | fgrep pname | sort -u | grep -P -- '-[0-9]+(\.[0-9]
"pname": "afro-graphics-theme-47.05",
"pname": "ajantv2-module-17.5.0-5.10.248",
"pname": "ajantv2-module-17.5.0-5.15.198",
"pname": "ajantv2-module-17.5.0-6.1.161",
"pname": "ajantv2-module-17.5.0-6.12.66",
"pname": "ajantv2-module-17.5.0-6.12.67",
"pname": "ajantv2-module-17.5.0-6.18.6",
"pname": "ajantv2-module-17.5.0-6.18.7",
"pname": "ajantv2-module-17.5.0-6.6.121",
"pname": "android-studio-for-platform-2024.2.2.13",
"pname": "android-studio-for-platform-canary-2024.3.1.9",
"pname": "auditable-cargo-1.92.0",
"pname": "autoreiv-theme-47.01",
"pname": "bbswitch-unstable-2021-11-29-5.10.248",
"pname": "bbswitch-unstable-2021-11-29-5.15.198",
"pname": "bbswitch-unstable-2021-11-29-6.1.161",
"pname": "bbswitch-unstable-2021-11-29-6.12.66",
"pname": "bbswitch-unstable-2021-11-29-6.12.67",
"pname": "bbswitch-unstable-2021-11-29-6.18.6",
"pname": "bbswitch-unstable-2021-11-29-6.18.7",
"pname": "bbswitch-unstable-2021-11-29-6.6.121",
"pname": "binary-black-2024-02-15",
"pname": "binary-blue-2024-02-15",
"pname": "binary-red-2024-02-15",
"pname": "binary-white-2024-02-15",
"pname": "broadcom-sta-6.30.223.271-59-5.10.248",
"pname": "broadcom-sta-6.30.223.271-59-5.15.198",
"pname": "broadcom-sta-6.30.223.271-59-6.1.161",
"pname": "broadcom-sta-6.30.223.271-59-6.12.66",
"pname": "broadcom-sta-6.30.223.271-59-6.12.67",
"pname": "broadcom-sta-6.30.223.271-59-6.18.6",
"pname": "broadcom-sta-6.30.223.271-59-6.18.7",
"pname": "broadcom-sta-6.30.223.271-59-6.6.121",
"pname": "bundler-audit-0.9.2",
"pname": "cabal2nix-2.21.0",
"pname": "caribou-0.4.21",
"pname": "catppuccin-frappe-2024-02-15",
"pname": "catppuccin-latte-2024-02-15",
"pname": "catppuccin-macchiato-2024-02-15",
"pname": "catppuccin-mocha-2024-02-15",
"pname": "cctools-binutils-darwin-dualas-1010.6",
"pname": "cfn-nag-0.8.10",
"pname": "chicken-base64-3.3.1",
"pname": "chicken-defstruct-1.6",
"pname": "chicken-http-client-0.18",
"pname": "chicken-intarweb-1.7",
"pname": "chicken-matchable-3.7",
"pname": "chicken-sendfile-1.8.3",
"pname": "chicken-simple-md5-0.0.1",
"pname": "chicken-uri-common-1.4",
"pname": "chicken-uri-generic-2.46",
"pname": "cloudformation-0.9.64",
"pname": "compass-1.0.3",
"pname": "d1x-rebirth-full-2.0.0.7",
"pname": "d2x-rebirth-full-2.0.0.7",
"pname": "dbus-1",
"pname": "deadbeef-with-plugins-1.10.0",
"pname": "dejavu-fonts-2.37",
"pname": "Dell-5130cdn-Color-Laser-1.3-1",
"pname": "dfgraphics-theme-42.05",
"pname": "distcc-masq-gcc-15.2.0",
"pname": "docbook-sgml-3.1",
"pname": "docbook-sgml-4.1",
"pname": "dracula-2020-07-02",
"pname": "drawio-headless-29.0.3",
"pname": "eclipse-plugin-antlr-runtime-4.5.3",
"pname": "eclipse-plugin-antlr-runtime-4.7.1",
"pname": "ecm-7.0.6",
"pname": "exact-audio-copy-1.8.0",
"pname": "faust2alqt-2.83.1",
"pname": "faust2alsa-2.83.1",
"pname": "faust2csound-2.83.1",
"pname": "faust2firefox-2.83.1",
"pname": "faust2jack-2.83.1",
"pname": "faust2jackrust-2.83.1",
"pname": "faust2jaqt-2.83.1",
"pname": "faust2ladspa-2.83.1",
"pname": "faust2lv2-2.83.1",
"pname": "faust2sc.py-2.83.1",
"pname": "faust2sndfile-2.83.1",
"pname": "fcitx5-with-addons-5.1.16",
"pname": "flare-1.14",
"pname": "fluentd-1.18.0",
"pname": "foreman-0.87.2",
"pname": "frogatto-unstable-2023-02-27",
"pname": "geany-with-vte-2.1",
"pname": "gear-2022-04-19",
"pname": "gemset-theme-47.05",
"pname": "gimp-with-plugins-2.10.38",
"pname": "gimp-with-plugins-3.0.6",
"pname": "git_fame-3.2.19",
"pname": "gitweb-2.52.0",
"pname": "glibc-iconv-2.42",
"pname": "glibc-multi-2.42-47",
"pname": "glob2-0.9.4.4",
"pname": "gradient-grey-2018-10-20",
"pname": "helm-3.19.1",
"pname": "hiera-eyaml-4.3.0",
"pname": "homesick-1.1.6",
"pname": "html-proofer-5.0.8",
"pname": "hxnodejs-6.9.0",
"pname": "ibus-with-plugins-1.5.33",
"pname": "idris-1.3.4",
"pname": "idris-with-packages-1.3.4",
"pname": "indi-full-2.1.6",
"pname": "indi-full-nonfree-2.1.6",
"pname": "indi-with-drivers-2.1.6",
"pname": "inkscape-with-extensions-1.4.3",
"pname": "ironhand-theme-47.05",
"pname": "jolly-bastion-theme-47.04",
"pname": "jool-4.1.14-5.10.248",
"pname": "jool-4.1.14-5.15.198",
"pname": "jool-4.1.14-6.1.161",
"pname": "jool-4.1.14-6.12.66",
"pname": "jool-4.1.14-6.12.67",
"pname": "jool-4.1.14-6.18.6",
"pname": "jool-4.1.14-6.18.7",
"pname": "jool-4.1.14-6.6.121",
"pname": "kakoune-2025.06.03",
"pname": "keeagent-0.12.0",
"pname": "keepass-charactercopy-1.0.0",
"pname": "keepasshttp-1.8.4.2",
"pname": "keepass-keetraytotp-0.108.0",
"pname": "keepass-qrcodeview-1.0.4",
"pname": "keepassrpc-1.16.0",
"pname": "klibc-2.0.14",
"pname": "legends-browser-1.19.2",
"pname": "libidn2-2.3.8",
"pname": "libxml2+py-2.15.1",
"pname": "license_finder-7.0.1",
"pname": "llvm-binutils-18.1.8",
"pname": "llvm-binutils-19.1.7",
"pname": "llvm-binutils-20.1.8",
"pname": "llvm-binutils-21.1.8",
"pname": "matrix-synapse-wrapped-1.145.0",
"pname": "mayday-theme-47.05",
"pname": "moonscape-2022-04-19",
"pname": "mosaic-blue-2016-02-19",
"pname": "mpv-with-scripts-0.41.0",
"pname": "msp430-newlib-4.5.0.20241231",
"pname": "nemo-with-extensions-6.6.3",
"pname": "net-tools-1003.1-2008",
"pname": "nineish-2019-12-04",
"pname": "nineish-catppuccin-frappe-2025-01-27",
"pname": "nineish-catppuccin-frappe-alt-2025-01-27",
"pname": "nineish-catppuccin-latte-2025-01-27",
"pname": "nineish-catppuccin-latte-alt-2025-01-27",
"pname": "nineish-catppuccin-macchiato-2025-01-27",
"pname": "nineish-catppuccin-macchiato-alt-2025-01-27",
"pname": "nineish-catppuccin-mocha-2025-01-27",
"pname": "nineish-catppuccin-mocha-alt-2025-01-27",
"pname": "nineish-dark-gray-2020-07-02",
"pname": "nineish-dark-gray-2021-07-20",
"pname": "nineish-dark-light-2021-07-20",
"pname": "nix-generate-from-cpan-3",
"pname": "nix-index-0.1.9",
"pname": "nixops-2.0.0-unstable-2025-12-28",
"pname": "obsidian-theme-47.05",
"pname": "ocaml5.3.0-uucp-17.0.0",
"pname": "ocaml5.3.0-vg-0.9.5",
"pname": "ocaml5.4.0-uucp-17.0.0",
"pname": "ocaml5.4.0-vg-0.9.5",
"pname": "open-watcom-bin-1.9",
"pname": "open-watcom-v2-0-unstable-2025-11-15",
"pname": "otpkeyprov-2.6",
"pname": "phoebus-theme-47.05",
"pname": "plikd-1.3.7",
"pname": "postgresql-plperl-14.20",
"pname": "postgresql-plperl-15.15",
"pname": "postgresql-plperl-16.11",
"pname": "postgresql-plperl-17.7",
"pname": "postgresql-plperl-18.1",
"pname": "postgresql-plpython3-14.20",
"pname": "postgresql-plpython3-15.15",
"pname": "postgresql-plpython3-16.11",
"pname": "postgresql-plpython3-17.7",
"pname": "postgresql-plpython3-18.1",
"pname": "postgresql-pltcl-14.20",
"pname": "postgresql-pltcl-15.15",
"pname": "postgresql-pltcl-16.11",
"pname": "postgresql-pltcl-17.7",
"pname": "postgresql-pltcl-18.1",
"pname": "postgrey-1.37",
"pname": "powerline-symbols-2.8.4",
"pname": "procps-1003.1-2008",
"pname": "python3.13-subunit-1.4.5",
"pname": "python3.14-subunit-1.4.5",
"pname": "python3-3.13.11-llm-0.28",
"pname": "rally-ho-theme-47.05",
"pname": "recursive-2022-04-19",
"pname": "retroarch-with-cores-1.22.2",
"pname": "roundcube-plugin-carddav-4.4.6",
"pname": "roundcube-plugin-contextmenu-3.3.1",
"pname": "roundcube-plugin-custom_from-1.6.6",
"pname": "roundcube-plugin-persistent_login-5.3.0",
"pname": "roundcube-plugin-thunderbird_labels-1.6.0",
"pname": "run-npush-0.7",
"pname": "scope-lite-0.2.0",
"pname": "service-wrapper-19.04",
"pname": "signwriting-1.1.4",
"pname": "simple-blue-2016-02-19",
"pname": "simple-dark-gray-2016-02-19",
"pname": "simple-dark-gray-2018-08-28",
"pname": "simple-dark-gray-bootloader-2018-08-28",
"pname": "simple-light-gray-2016-02-19",
"pname": "simple-red-2016-02-19",
"pname": "stripes-2016-02-19",
"pname": "stripes-logo-2016-02-19",
"pname": "system76-io-module-1.0.4-5.10.248",
"pname": "system76-io-module-1.0.4-5.15.198",
"pname": "system76-io-module-1.0.4-6.1.161",
"pname": "system76-io-module-1.0.4-6.12.66",
"pname": "system76-io-module-1.0.4-6.12.67",
"pname": "system76-io-module-1.0.4-6.18.6",
"pname": "system76-io-module-1.0.4-6.18.7",
"pname": "system76-io-module-1.0.4-6.6.121",
"pname": "system76-module-1.0.17-5.10.248",
"pname": "system76-module-1.0.17-5.15.198",
"pname": "system76-module-1.0.17-6.1.161",
"pname": "system76-module-1.0.17-6.12.66",
"pname": "system76-module-1.0.17-6.12.67",
"pname": "system76-module-1.0.17-6.18.6",
"pname": "system76-module-1.0.17-6.18.7",
"pname": "system76-module-1.0.17-6.6.121",
"pname": "systemtap-5.4",
"pname": "taffer-theme-47.04",
"pname": "teamocil-1.4.2",
"pname": "tectonic-wrapped-0.15.0",
"pname": "tergel-theme-47.01",
"pname": "travis-1.9.1",
"pname": "tsm-client-8.1.27.1",
"pname": "unicode-emoji-17.0.0",
"pname": "usbip-linux-5.10.248",
"pname": "usbip-linux-5.15.198",
"pname": "usbip-linux-6.1.161",
"pname": "usbip-linux-6.12.67",
"pname": "usbip-linux-6.18.7",
"pname": "usbip-linux-6.6.121",
"pname": "usbip-linux-hardened-6.12.66",
"pname": "usbip-linux-lqx-6.18.6",
"pname": "usbip-linux-xanmod-6.12.66",
"pname": "usbip-linux-xanmod-6.18.6",
"pname": "usbip-linux-zen-6.18.6",
"pname": "util-linux-1003.1-2008",
"pname": "vdr-epgtableid0-2.6.9",
"pname": "vdr-hello-2.6.9",
"pname": "vdrift-unstable-2021-09-05-with-data-1446",
"pname": "vdr-osddemo-2.6.9",
"pname": "vdr-pictures-2.6.9",
"pname": "vdr-servicedemo-2.6.9",
"pname": "vdr-skincurses-2.6.9",
"pname": "vdr-status-2.6.9",
"pname": "vdr-svdrpdemo-2.6.9",
"pname": "vdr-with-plugins-2.6.9",
"pname": "vettlingr-theme-47.05",
"pname": "vscode-with-extensions-1.108.1",
"pname": "wanderlust-theme-47.04",
"pname": "waterfall-2022-04-19",
"pname": "watersplash-2022-04-19",
"pname": "wayfire-wrapped-0.10.1",At least flare is in the list. I think most of these require a similar
fix.
Parting words
nixpkgs now exposes slight less mangled data to repology.org for version
comparison. Unfortunately nixpkgs itself is not fully switched to
pname / version everywhere. And thus a small set of data is now lost.
It should be easy to find and to restore those with a fix similar to
flare.
Have fun!