nixfmt[-rfc-style]: unstable -> 1.0.0 (#425068)

ci/default.nix

@@ -49,7 +49,7 @@ let
 
         programs.keep-sorted.enable = true;
 
-        # This uses nixfmt-rfc-style underneath,
+        # This uses nixfmt underneath,
         # the default formatter for Nix code.
         # See https://github.com/NixOS/nixfmt
         programs.nixfmt.enable = true;

doc/release-notes/rl-2511.section.md

@@ -8,6 +8,7 @@
   this release sets the default march level to `la64v1.0`, covering the desktop and server processors of 3X5000
   and newer series. However, embedded chips without LSX (Loongson SIMD eXtension), such as 2K0300 SoC, are not
   supported. `pkgsCross.loongarch64-linux-embedded` can be used to build software and systems for these platforms.
+- The official Nix formatter `nixfmt` is now stable and available as `pkgs.nixfmt`, deprecating the temporary `pkgs.nixfmt-rfc-style` attribute. The classic `nixfmt` will stay available for some more time as `pkgs.nixfmt-classic`.
 
 ## Backward Incompatibilities {#sec-nixpkgs-release-25.11-incompatibilities}
 

maintainers/scripts/auto-rebase/test/default.nix

@@ -9,7 +9,7 @@ let
     stdenvNoCC
     gitMinimal
     treefmt
-    nixfmt-rfc-style
+    nixfmt
     ;
 in
 
@@ -27,7 +27,7 @@ stdenvNoCC.mkDerivation {
   nativeBuildInputs = [
     gitMinimal
     treefmt
-    nixfmt-rfc-style
+    nixfmt
   ];
   patchPhase = ''
     patchShebangs .

maintainers/scripts/haskell/regenerate-hackage-packages.sh

@@ -1,5 +1,5 @@
 #! /usr/bin/env nix-shell
-#! nix-shell -i bash -p coreutils haskellPackages.cabal2nix-unstable git nixfmt-rfc-style -I nixpkgs=.
+#! nix-shell -i bash -p coreutils haskellPackages.cabal2nix-unstable git -I nixpkgs=.
 
 set -euo pipefail
 

maintainers/scripts/haskell/update-cabal2nix-unstable.sh

@@ -1,5 +1,5 @@
 #! /usr/bin/env nix-shell
-#! nix-shell -i bash -p coreutils curl jq gnused haskellPackages.cabal2nix-unstable nixfmt-rfc-style -I nixpkgs=.
+#! nix-shell -i bash -p coreutils curl jq gnused haskellPackages.cabal2nix-unstable -I nixpkgs=.
 
 # Updates cabal2nix-unstable to the latest master of the nixos/cabal2nix repository.
 # See regenerate-hackage-packages.sh for details on the purpose of this script.

maintainers/scripts/update.py

@@ -7,6 +7,7 @@ import contextlib
 import json
 import os
 import re
+import shlex
 import subprocess
 import sys
 import tempfile
@@ -235,7 +236,11 @@ async def run_update_script(
             f"UPDATE_NIX_PNAME={package['pname']}",
             f"UPDATE_NIX_OLD_VERSION={package['oldVersion']}",
             f"UPDATE_NIX_ATTR_PATH={package['attrPath']}",
-            *update_script_command,
+            # Run all update scripts in the Nixpkgs development shell to get access to formatters and co.
+            "nix-shell",
+            nixpkgs_root + "/shell.nix",
+            "--run",
+            " ".join([ shlex.quote(s) for s in update_script_command ]),
             stdout=asyncio.subprocess.PIPE,
             stderr=asyncio.subprocess.PIPE,
             cwd=worktree,

pkgs/README.md

@@ -940,7 +940,8 @@ Update scripts are to be invoked by the [automatic package update script](../mai
 You can run `nix-shell maintainers/scripts/update.nix` in the root of Nixpkgs repository for information on how to use it.
 `update.nix` offers several modes for selecting packages to update, and it will execute update scripts for all matched packages that have an `updateScript` attribute.
 
-Each update script will be passed the following environment variables:
+Update scripts will be run inside the [Nixpkgs development shell](../shell.nix), providing access to some useful tools for CI.
+Furthermore each update script will be passed the following environment variables:
 
 - [`UPDATE_NIX_NAME`] – content of the `name` attribute of the updated package
 - [`UPDATE_NIX_PNAME`] – content of the `pname` attribute of the updated package

pkgs/applications/editors/emacs/elisp-packages/emacs2nix.nix

@@ -13,7 +13,7 @@ pkgs.mkShell {
 
   packages = [
     pkgs.bash
-    pkgs.nixfmt-rfc-style
+    pkgs.nixfmt
   ];
 
   EMACS2NIX = src;

pkgs/build-support/dotnet/add-nuget-deps/default.nix

@@ -5,7 +5,7 @@
   lib,
   replaceVarsWith,
   nuget-to-nix,
-  nixfmt-rfc-style,
+  nixfmt,
   nuget-to-json,
   cacert,
   fetchNupkg,
@@ -90,7 +90,7 @@ attrs
             replacements = {
               binPath = lib.makeBinPath [
                 nuget-to-nix
-                nixfmt-rfc-style
+                nixfmt
                 nuget-to-json
               ];
             };

pkgs/build-support/vm/default.nix

@@ -909,7 +909,7 @@ rec {
         nativeBuildInputs = [
           buildPackages.perl
           buildPackages.dpkg
-          buildPackages.nixfmt-rfc-style
+          buildPackages.nixfmt
         ];
       }
       ''

pkgs/by-name/br/bruijn/update.sh

@@ -1,5 +1,5 @@
 #!/usr/bin/env nix-shell
-#!nix-shell -i bash -p coreutils cabal2nix curl jq nixfmt-rfc-style
+#!nix-shell -i bash -p coreutils cabal2nix curl jq
 
 set -euo pipefail
 

pkgs/by-name/cr/creek/update.sh

@@ -1,5 +1,5 @@
 #!/usr/bin/env nix-shell
-#!nix-shell -i bash -p bash common-updater-scripts gnused nixfmt-rfc-style
+#!nix-shell -i bash -p bash common-updater-scripts gnused
 
 latest_tag=$(list-git-tags --url=https://github.com/nmeum/creek | sed 's/^v//' | tail -n 1)
 

pkgs/by-name/dp/dprint/plugins/update-plugins.py

@@ -1,5 +1,5 @@
 #!/usr/bin/env nix-shell
-#!nix-shell -i python -p nix nixfmt-rfc-style 'python3.withPackages (pp: [ pp.requests ])'
+#!nix-shell -i python -p nix 'python3.withPackages (pp: [ pp.requests ])'
 
 import json
 import os

pkgs/by-name/ej/ejabberd/update.sh

@@ -1,5 +1,5 @@
 #!/usr/bin/env nix-shell
-#!nix-shell -I nixpkgs=./. -i bash -p curl jq common-updater-scripts "rebar3WithPlugins {globalPlugins = [beamPackages.rebar3-nix];}" erlang autoconf automake nixfmt-rfc-style
+#!nix-shell -I nixpkgs=./. -i bash -p curl jq common-updater-scripts "rebar3WithPlugins {globalPlugins = [beamPackages.rebar3-nix];}" erlang autoconf automake
 #shellcheck shell=bash
 
 set -eu -o pipefail

pkgs/by-name/el/elm-land/package.nix

@@ -7,7 +7,7 @@
   writeShellScript,
   nix-update,
   elm2nix,
-  nixfmt-rfc-style,
+  nixfmt,
 }:
 
 buildNpmPackage rec {
@@ -53,7 +53,7 @@ buildNpmPackage rec {
     cp "$(nix-build -A "$UPDATE_NIX_ATTR_PATH".src)/projects/cli/src/codegen/elm.json" elm.json
     trap 'rm -rf elm.json registry.dat &> /dev/null' EXIT
     ${lib.getExe elm2nix} convert > pkgs/by-name/el/elm-land/elm-srcs.nix
-    ${lib.getExe nixfmt-rfc-style} pkgs/by-name/el/elm-land/elm-srcs.nix
+    ${lib.getExe nixfmt} pkgs/by-name/el/elm-land/elm-srcs.nix
     ${lib.getExe elm2nix} snapshot
     cp registry.dat pkgs/by-name/el/elm-land/registry.dat
   '';

pkgs/by-name/fl/flow-control/update.sh

@@ -1,5 +1,5 @@
 #!/usr/bin/env nix-shell
-#!nix-shell -i bash -p bash common-updater-scripts gnused nixfmt-rfc-style
+#!nix-shell -i bash -p bash common-updater-scripts gnused
 
 latest_tag=$(list-git-tags --url=https://github.com/neurocyte/flow | sed 's/^v//' | tail -n 1)
 

pkgs/by-name/gr/gren/update.sh

@@ -1,5 +1,5 @@
 #!/usr/bin/env nix-shell
-#!nix-shell -i bash -p cabal2nix curl jq nixfmt-rfc-style
+#!nix-shell -i bash -p cabal2nix curl jq
 
 set -euo pipefail
 

pkgs/by-name/li/livekit-libwebrtc/gclient2nix.nix

@@ -8,7 +8,7 @@
   nix-prefetch-git,
   nix,
   coreutils,
-  nixfmt-rfc-style,
+  nixfmt,
   makeWrapper,
 }:
 # Based on https://github.com/milahu/gclient2nix
@@ -19,7 +19,7 @@ let
     nix-prefetch-git
     nix
     coreutils
-    nixfmt-rfc-style
+    nixfmt
   ];
 in
 buildPythonPackage {

pkgs/by-name/ms/msgraph-cli/update.sh

@@ -1,5 +1,5 @@
 #!/usr/bin/env nix-shell
-#!nix-shell -i bash -p curl gnused nixfmt-rfc-style common-updater-scripts
+#!nix-shell -i bash -p curl gnused common-updater-scripts
 set -eEuo pipefail
 [ -z "${DEBUG:-}" ] || set -x
 cd "${BASH_SOURCE[0]%/*}"

pkgs/by-name/mu/music-assistant/update-providers.py

@@ -1,5 +1,5 @@
 #!/usr/bin/env nix-shell
-#!nix-shell -I nixpkgs=./. -i python3 -p "music-assistant.python.withPackages (ps: music-assistant.dependencies ++ (with ps; [ jinja2 packaging ]))" -p pyright ruff isort nixfmt-rfc-style
+#!nix-shell -I nixpkgs=./. -i python3 -p "music-assistant.python.withPackages (ps: music-assistant.dependencies ++ (with ps; [ jinja2 packaging ]))" -p pyright ruff isort
 import asyncio
 import json
 import os.path

pkgs/by-name/ni/nil/package.nix

@@ -3,7 +3,7 @@
   rustPlatform,
   fetchFromGitHub,
   nix,
-  nixfmt-rfc-style,
+  nixfmt,
   nix-update-script,
 }:
 
@@ -25,7 +25,7 @@ rustPlatform.buildRustPackage rec {
 
   env = {
     CFG_RELEASE = version;
-    CFG_DEFAULT_FORMATTER = lib.getExe nixfmt-rfc-style;
+    CFG_DEFAULT_FORMATTER = lib.getExe nixfmt;
   };
 
   # might be related to https://github.com/NixOS/nix/issues/5884

pkgs/by-name/ni/nixfmt-rfc-style/date.txt

@@ -1 +0,0 @@
-2025-04-04

pkgs/by-name/ni/nixfmt-rfc-style/update.sh

@@ -1,33 +0,0 @@
-#!/usr/bin/env nix-shell
-#!nix-shell -i bash -p cabal2nix curl jq
-#
-# This script will update the nixfmt-rfc-style derivation to the latest version using
-# cabal2nix.
-
-set -eo pipefail
-
-# This is the directory of this update.sh script.
-script_dir="$( cd "$( dirname "${BASH_SOURCE[0]}" )" >/dev/null 2>&1 && pwd )"
-
-derivation_file="${script_dir}/generated-package.nix"
-date_file="${script_dir}/date.txt"
-
-# This is the latest version of nixfmt-rfc-style branch on GitHub.
-new_version=$(curl --silent https://api.github.com/repos/nixos/nixfmt/git/refs/heads/master | jq '.object.sha' --raw-output)
-new_date=$(curl --silent https://api.github.com/repos/nixos/nixfmt/git/commits/"$new_version" | jq '.committer.date' --raw-output)
-
-echo "Updating nixfmt-rfc-style to version $new_date."
-echo "Running cabal2nix and outputting to ${derivation_file}..."
-
-cat > "$derivation_file" << EOF
-# This file has been autogenerate with cabal2nix.
-# Update via ./update.sh
-EOF
-
-cabal2nix --jailbreak \
-  "https://github.com/nixos/nixfmt/archive/${new_version}.tar.gz" \
-  >> "$derivation_file"
-
-date --date="$new_date" -I > "$date_file"
-
-echo "Finished."

pkgs/by-name/ni/nixfmt-tree/package.nix

@@ -2,14 +2,14 @@
   lib,
   runCommand,
   treefmt,
-  nixfmt-rfc-style,
+  nixfmt,
   nixfmt-tree,
   git,
   writableTmpDirAsHomeHook,
 
   settings ? { },
   runtimeInputs ? [ ],
-  nixfmtPackage ? nixfmt-rfc-style,
+  nixfmtPackage ? nixfmt,
 
   # NOTE: `runtimePackages` is deprecated. Use `nixfmtPackage` and/or `runtimeInputs`.
   runtimePackages ? [ nixfmtPackage ],

pkgs/by-name/ni/nixfmt/generated-package.nix

@@ -23,10 +23,10 @@
 }:
 mkDerivation {
   pname = "nixfmt";
-  version = "0.6.0";
+  version = "1.0.0";
   src = fetchzip {
-    url = "https://github.com/nixos/nixfmt/archive/65af4b69133d19f534d97746c97c2d5b464f43b4.tar.gz";
-    sha256 = "0l0w3janvss1n1j7qkcml97zndm2jm2gbrzzs9d8l0ixnrw0cd5r";
+    url = "https://github.com/nixos/nixfmt/archive/v1.0.0.tar.gz";
+    sha256 = "0iy2p893b2b5y4mvhy0d62675a7nd8fc6jm9mr32v9h2baj9ii3p";
   };
   isLibrary = true;
   isExecutable = true;

pkgs/by-name/ni/nixfmt/package.nix

@@ -3,30 +3,22 @@
   haskellPackages,
   lib,
   runCommand,
-  nixfmt-rfc-style,
+  nixfmt,
 }:
 let
   inherit (haskell.lib.compose) overrideCabal justStaticExecutables;
 
-  overrides = rec {
-    version = "unstable-${lib.fileContents ./date.txt}";
-
+  overrides = {
     passthru.updateScript = ./update.sh;
 
     teams = [ lib.teams.formatter ];
 
-    preBuild = ''
-      echo -n 'nixpkgs-${version}' > .version
-    '';
-
     # These tests can be run with the following command.
     #
-    # $ nix-build -A nixfmt-rfc-style.tests
-    passthru.tests =
-      runCommand "nixfmt-rfc-style-tests" { nativeBuildInputs = [ nixfmt-rfc-style ]; }
-        ''
-          nixfmt --version > $out
-        '';
+    # $ nix-build -A nixfmt.tests
+    passthru.tests = runCommand "nixfmt-tests" { nativeBuildInputs = [ nixfmt ]; } ''
+      nixfmt --version > $out
+    '';
   };
   raw-pkg = haskellPackages.callPackage ./generated-package.nix { };
 in

pkgs/by-name/ni/nixfmt/update.sh

@@ -0,0 +1,27 @@
+#!/usr/bin/env nix-shell
+#!nix-shell -i bash -p cabal2nix curl jq
+#
+# This script will update the nixfmt derivation to the latest version using
+# cabal2nix.
+
+set -eo pipefail
+
+# This is the directory of this update.sh script.
+script_dir="$( cd "$( dirname "${BASH_SOURCE[0]}" )" >/dev/null 2>&1 && pwd )"
+derivation_file="${script_dir}/generated-package.nix"
+
+release_tag=$(curl --silent https://api.github.com/repos/NixOS/nixfmt/releases/latest | jq '.tag_name' --raw-output)
+
+echo "Updating nixfmt to version $release_tag."
+echo "Running cabal2nix and outputting to ${derivation_file}..."
+
+cat > "$derivation_file" << EOF
+# This file has been autogenerate with cabal2nix.
+# Update via ./update.sh
+EOF
+
+cabal2nix --jailbreak \
+  "https://github.com/nixos/nixfmt/archive/${release_tag}.tar.gz" \
+  >> "$derivation_file"
+
+echo "Finished."

pkgs/by-name/oa/oama/update.sh

@@ -1,5 +1,5 @@
 #!/usr/bin/env nix-shell
-#!nix-shell -i bash -p haskell.packages.ghc910.cabal2nix nix-prefetch-git curl jq nixfmt-rfc-style
+#!nix-shell -i bash -p haskell.packages.ghc910.cabal2nix nix-prefetch-git curl jq
 
 set -euo pipefail
 

pkgs/by-name/ri/river-bedload/update-build-zig-zon.sh

@@ -1,5 +1,5 @@
 #!/usr/bin/env nix-shell
-#!nix-shell -i bash -p bash jq nixfmt-rfc-style zon2nix
+#!nix-shell -i bash -p bash jq zon2nix
 
 commit=$(nix-instantiate --eval -A river-bedload.src.rev | jq --raw-output)
 

pkgs/by-name/ri/river/update.sh

@@ -1,5 +1,5 @@
 #!/usr/bin/env nix-shell
-#!nix-shell -i bash -p bash common-updater-scripts gnused nixfmt-rfc-style zon2nix
+#!nix-shell -i bash -p bash common-updater-scripts gnused zon2nix
 
 latest_tag=$(list-git-tags --url=https://codeberg.org/river/river | sed 's/^v//' | sort --version-sort | tail --lines=1)
 

pkgs/by-name/tr/treefmt/tests.nix

@@ -3,7 +3,7 @@
   runCommand,
   testers,
   treefmt,
-  nixfmt-rfc-style,
+  nixfmt,
 }:
 let
   inherit (treefmt) buildConfig withConfig;
@@ -29,7 +29,7 @@ let
 
   nixfmtExamplePackage = withConfig {
     settings = nixfmtExampleConfig;
-    runtimeInputs = [ nixfmt-rfc-style ];
+    runtimeInputs = [ nixfmt ];
   };
 in
 {

pkgs/by-name/wa/waylock/update.sh

@@ -1,5 +1,5 @@
 #!/usr/bin/env nix-shell
-#!nix-shell -i bash -p bash common-updater-scripts gnused nixfmt-rfc-style zon2nix
+#!nix-shell -i bash -p bash common-updater-scripts gnused zon2nix
 
 latest_tag=$(list-git-tags --url=https://codeberg.org/ifreund/waylock | sed 's/^v//' | tail -n 1)
 

pkgs/development/beam-modules/elvis-erlang/default.nix

@@ -29,7 +29,7 @@ rebar3Relx rec {
 
   passthru.updateScript = writeScript "update.sh" ''
     #!/usr/bin/env nix-shell
-    #!nix-shell -i bash -p bash common-updater-scripts git nix-prefetch-git gnutar gzip "rebar3WithPlugins {globalPlugins = [beamPackages.rebar3-nix];}" nixfmt-rfc-style
+    #!nix-shell -i bash -p bash common-updater-scripts git nix-prefetch-git gnutar gzip "rebar3WithPlugins {globalPlugins = [beamPackages.rebar3-nix];}"
 
     set -euo pipefail
 

pkgs/development/beam-modules/erlang-ls/default.nix

@@ -74,7 +74,7 @@ rebar3Relx {
 
   passthru.updateScript = writeScript "update.sh" ''
     #!/usr/bin/env nix-shell
-    #! nix-shell -i bash -p common-updater-scripts coreutils git gnused gnutar gzip nixfmt-rfc-style "rebar3WithPlugins { globalPlugins = [ beamPackages.rebar3-nix ]; }"
+    #! nix-shell -i bash -p common-updater-scripts coreutils git gnused gnutar gzip "rebar3WithPlugins { globalPlugins = [ beamPackages.rebar3-nix ]; }"
 
     set -ox errexit
     latest=$(list-git-tags | sed -n '/[\d\.]\+/p' | sort -V | tail -1)

pkgs/development/compilers/dotnet/update.sh

@@ -1,5 +1,5 @@
 #!/usr/bin/env nix-shell
-#!nix-shell -I nixpkgs=./. -i bash -p curl jq nix gnused nixfmt-rfc-style
+#!nix-shell -I nixpkgs=./. -i bash -p curl jq nix gnused
 # shellcheck shell=bash
 
 set -Eeuo pipefail

pkgs/development/ruby-modules/bundler-update-script/default.nix

@@ -7,7 +7,7 @@
   coreutils,
   git,
   nix,
-  nixfmt-rfc-style,
+  nixfmt,
 }:
 
 attrPath:
@@ -22,7 +22,7 @@ let
         coreutils
         git
         nix
-        nixfmt-rfc-style
+        nixfmt
       ]
     }
     set -o errexit

pkgs/development/tools/build-managers/rebar3/default.nix

@@ -12,7 +12,7 @@
   git,
   gnused,
   nix,
-  nixfmt-rfc-style,
+  nixfmt,
   rebar3-nix,
 }:
 
@@ -95,7 +95,7 @@ let
           git
           gnused
           nix
-          nixfmt-rfc-style
+          nixfmt
           (rebar3WithPlugins { globalPlugins = [ rebar3-nix ]; })
         ]
       }

pkgs/servers/home-assistant/update-component-packages.py

@@ -1,5 +1,5 @@
 #! /usr/bin/env nix-shell
-#! nix-shell -i python3 -p "python3.withPackages (ps: with ps; [ packaging rich ])" -p pyright ruff isort nixfmt-rfc-style
+#! nix-shell -i python3 -p "python3.withPackages (ps: with ps; [ packaging rich ])" -p pyright ruff isort
 #
 # This script downloads Home Assistant's source tarball.
 # Inside the homeassistant/components directory, each integration has an associated manifest.json,

pkgs/servers/mobilizon/default.nix

@@ -8,7 +8,7 @@
   git,
   cmake,
   nixosTests,
-  nixfmt-rfc-style,
+  nixfmt,
   mobilizon-frontend,
   ...
 }:
@@ -145,7 +145,7 @@ mixRelease rec {
       set -eou pipefail
 
       ${lib.getExe mix2nix} '${src}/mix.lock' > pkgs/servers/mobilizon/mix.nix
-      ${lib.getExe nixfmt-rfc-style} pkgs/servers/mobilizon/mix.nix
+      ${lib.getExe nixfmt} pkgs/servers/mobilizon/mix.nix
     '';
     elixirPackage = beamPackages.elixir;
   };

pkgs/tools/typesetting/tex/texlive/default.nix

@@ -43,7 +43,7 @@
   makeFontsConf,
   useFixedHashes ? true,
   recurseIntoAttrs,
-  nixfmt-rfc-style,
+  nixfmt,
 }:
 let
   stdenv = gcc12Stdenv;
@@ -151,7 +151,7 @@ let
         tl2nix = ./tl2nix.sed;
       }
       ''
-        xzcat "$tlpdbxz" | sed -rn -f "$tl2nix" | uniq | ${lib.getExe nixfmt-rfc-style} > "$out"
+        xzcat "$tlpdbxz" | sed -rn -f "$tl2nix" | uniq | ${lib.getExe nixfmt} > "$out"
       '';
 
   # map: name -> fixed-output hash

pkgs/top-level/aliases.nix

@@ -1412,7 +1412,13 @@ mapAliases {
   nixStable = nixVersions.stable; # Added 2022-01-24
   nixUnstable = throw "nixUnstable has been removed. For bleeding edge (Nix master, roughly weekly updated) use nixVersions.git, otherwise use nixVersions.latest."; # Converted to throw 2024-04-22
   nix_2_3 = nixVersions.nix_2_3;
-  nixfmt = lib.warnOnInstantiate "nixfmt was renamed to nixfmt-classic. The nixfmt attribute may be used for the new RFC 166-style formatter in the future, which is currently available as nixfmt-rfc-style" nixfmt-classic; # Added 2024-03-31
+  nixfmt-rfc-style =
+    if lib.oldestSupportedReleaseIsAtLeast 2511 then
+      lib.warnOnInstantiate
+        "nixfmt-rfc-style is now the same as pkgs.nixfmt which should be used instead."
+        nixfmt # Added 2025-07-14
+    else
+      nixfmt;
 
   # When the nixops_unstable alias is removed, nixops_unstable_minimal can be renamed to nixops_unstable.
 

pkgs/top-level/release-haskell.nix

@@ -346,7 +346,7 @@ let
         nix-script
         nix-tree
         nixfmt-classic
-        nixfmt-rfc-style
+        nixfmt
         nota
         nvfetcher
         oama