diff --git a/pkgs/data/themes/adwaita-qt/default.nix b/pkgs/by-name/ad/adwaita-qt/package.nix
similarity index 84%
rename from pkgs/data/themes/adwaita-qt/default.nix
rename to pkgs/by-name/ad/adwaita-qt/package.nix
index aa80c27297ad..7f2ea1b256f1 100644
--- a/pkgs/data/themes/adwaita-qt/default.nix
+++ b/pkgs/by-name/ad/adwaita-qt/package.nix
@@ -5,14 +5,16 @@
   nix-update-script,
   cmake,
   ninja,
-  qtbase,
-  qtwayland,
   qt5,
+  qt6,
   libxcb,
   useQt6 ? false,
 }:
+let
+  qt = if useQt6 then qt6 else qt5;
+in
 
-stdenv.mkDerivation rec {
+stdenv.mkDerivation (finalAttrs: {
   pname = "adwaita-qt";
   version = "1.4.2";
 
@@ -24,8 +26,8 @@ stdenv.mkDerivation rec {
   src = fetchFromGitHub {
     owner = "FedoraQt";
     repo = "adwaita-qt";
-    rev = version;
-    sha256 = "sha256-K/+SL52C+M2OC4NL+mhBnm/9BwH0KNNTGIDmPwuUwkM=";
+    tag = finalAttrs.version;
+    hash = "sha256-K/+SL52C+M2OC4NL+mhBnm/9BwH0KNNTGIDmPwuUwkM=";
   };
 
   nativeBuildInputs = [
@@ -34,7 +36,7 @@ stdenv.mkDerivation rec {
   ];
 
   buildInputs = [
-    qtbase
+    qt.qtbase
   ]
   ++ lib.optionals stdenv.hostPlatform.isLinux [
     libxcb
@@ -43,7 +45,7 @@ stdenv.mkDerivation rec {
     qt5.qtx11extras
   ]
   ++ lib.optionals useQt6 [
-    qtwayland
+    qt6.qtwayland
   ];
 
   # Qt setup hook complains about missing `wrapQtAppsHook` otherwise.
@@ -70,4 +72,4 @@ stdenv.mkDerivation rec {
     maintainers = [ ];
     platforms = lib.platforms.all;
   };
-}
+})
diff --git a/pkgs/servers/dcnnt/default.nix b/pkgs/by-name/dc/dcnnt/package.nix
similarity index 78%
rename from pkgs/servers/dcnnt/default.nix
rename to pkgs/by-name/dc/dcnnt/package.nix
index 6f82a28ff33a..94b8eb16446f 100644
--- a/pkgs/servers/dcnnt/default.nix
+++ b/pkgs/by-name/dc/dcnnt/package.nix
@@ -1,21 +1,20 @@
 {
-  buildPythonApplication,
-  fetchPypi,
   lib,
-  pycryptodome,
+  python3Packages,
+  fetchPypi,
 }:
 
-buildPythonApplication rec {
+python3Packages.buildPythonApplication (finalAttrs: {
   pname = "dcnnt";
   version = "0.10.0";
   format = "setuptools";
 
   src = fetchPypi {
-    inherit pname version;
+    inherit (finalAttrs) pname version;
     hash = "sha256-73ZLgb5YcXlAOjbKLVv8oqgS6pstBdJxa7LFUgIHpUE=";
   };
 
-  propagatedBuildInputs = [
+  propagatedBuildInputs = with python3Packages; [
     pycryptodome
   ];
 
@@ -30,4 +29,4 @@ buildPythonApplication rec {
     maintainers = with lib.maintainers; [ arnoutkroeze ];
     mainProgram = "dcnnt";
   };
-}
+})
diff --git a/pkgs/servers/isso/default.nix b/pkgs/by-name/is/isso/package.nix
similarity index 69%
rename from pkgs/servers/isso/default.nix
rename to pkgs/by-name/is/isso/package.nix
index e92390f8c982..2b1959ae6203 100644
--- a/pkgs/servers/isso/default.nix
+++ b/pkgs/by-name/is/isso/package.nix
@@ -1,16 +1,14 @@
 {
-  nodejs,
   lib,
   python3Packages,
   fetchFromGitHub,
   nixosTests,
   fetchNpmDeps,
+  nodejs_20,
   npmHooks,
 }:
 
-with python3Packages;
-
-buildPythonApplication rec {
+python3Packages.buildPythonApplication (finalAttrs: {
   pname = "isso";
   version = "0.13.0";
   format = "setuptools";
@@ -18,12 +16,12 @@ buildPythonApplication rec {
   src = fetchFromGitHub {
     owner = "posativ";
     repo = "isso";
-    tag = version;
-    sha256 = "sha256-kZNf7Rlb1DZtQe4dK1B283OkzQQcCX+pbvZzfL65gsA=";
+    tag = finalAttrs.version;
+    hash = "sha256-kZNf7Rlb1DZtQe4dK1B283OkzQQcCX+pbvZzfL65gsA=";
   };
 
   npmDeps = fetchNpmDeps {
-    inherit src;
+    inherit (finalAttrs) src;
     hash = "sha256-RBpuhFI0hdi8bB48Pks9Ac/UdcQ/DJw+WFnNj5f7IYE=";
   };
 
@@ -38,7 +36,7 @@ buildPythonApplication rec {
       --replace "self.client.delete_cookie('localhost.local', '1')" "self.client.delete_cookie(key='1', domain='localhost')"
   '';
 
-  propagatedBuildInputs = [
+  propagatedBuildInputs = with python3Packages; [
     itsdangerous
     jinja2
     misaka
@@ -49,25 +47,25 @@ buildPythonApplication rec {
   ];
 
   nativeBuildInputs = [
-    cffi
-    sphinxHook
-    sphinx
-    nodejs
+    python3Packages.cffi
+    python3Packages.sphinxHook
+    python3Packages.sphinx
+    nodejs_20
     npmHooks.npmConfigHook
   ];
 
   NODE_PATH = "$npmDeps";
 
   preBuild = ''
-    ln -s ${npmDeps}/node_modules ./node_modules
-    export PATH="${npmDeps}/bin:$PATH"
+    ln -s ${finalAttrs.npmDeps}/node_modules ./node_modules
+    export PATH="${finalAttrs.npmDeps}/bin:$PATH"
 
     make js
   '';
 
   nativeCheckInputs = [
-    pytestCheckHook
-    pytest-cov-stub
+    python3Packages.pytestCheckHook
+    python3Packages.pytest-cov-stub
   ];
 
   passthru.tests = { inherit (nixosTests) isso; };
@@ -79,4 +77,4 @@ buildPythonApplication rec {
     license = lib.licenses.mit;
     maintainers = with lib.maintainers; [ fgaz ];
   };
-}
+})
diff --git a/pkgs/servers/jackett/deps.json b/pkgs/by-name/ja/jackett/deps.json
similarity index 100%
rename from pkgs/servers/jackett/deps.json
rename to pkgs/by-name/ja/jackett/deps.json
diff --git a/pkgs/servers/jackett/default.nix b/pkgs/by-name/ja/jackett/package.nix
similarity index 82%
rename from pkgs/servers/jackett/default.nix
rename to pkgs/by-name/ja/jackett/package.nix
index 08e6b4f419e6..0f515a25017d 100644
--- a/pkgs/servers/jackett/default.nix
+++ b/pkgs/by-name/ja/jackett/package.nix
@@ -6,17 +6,18 @@
   dotnetCorePackages,
   openssl,
   mono,
+  nix-update-script,
   nixosTests,
 }:
 
-buildDotnetModule rec {
+buildDotnetModule (finalAttrs: {
   pname = "jackett";
   version = "0.24.1066";
 
   src = fetchFromGitHub {
     owner = "jackett";
     repo = "jackett";
-    tag = "v${version}";
+    tag = "v${finalAttrs.version}";
     hash = "sha256-o0Mu5+m6+2iVRIJ8OIlUDNUY9h3qKn1hOsSA1JYd71o=";
   };
 
@@ -32,7 +33,7 @@ buildDotnetModule rec {
   ];
 
   postPatch = ''
-    substituteInPlace ${projectFile} ${testProjectFile} \
+    substituteInPlace ${finalAttrs.projectFile} ${finalAttrs.testProjectFile} \
       --replace-fail '<TargetFrameworks>net9.0;net471</' '<TargetFrameworks>net9.0</'
   '';
 
@@ -49,19 +50,21 @@ buildDotnetModule rec {
     ln -s $out/bin/jackett $out/bin/Jackett || :
     ln -s $out/bin/Jackett $out/bin/jackett || :
   '';
-  passthru.updateScript = ./updater.sh;
 
-  passthru.tests = { inherit (nixosTests) jackett; };
+  passthru = {
+    updateScript = nix-update-script { };
+    tests = { inherit (nixosTests) jackett; };
+  };
 
   meta = {
     description = "API Support for your favorite torrent trackers";
     mainProgram = "jackett";
     homepage = "https://github.com/Jackett/Jackett/";
-    changelog = "https://github.com/Jackett/Jackett/releases/tag/v${version}";
+    changelog = "https://github.com/Jackett/Jackett/releases/tag/v${finalAttrs.version}";
     license = lib.licenses.gpl2Only;
     maintainers = with lib.maintainers; [
       nyanloutre
       purcell
     ];
   };
-}
+})
diff --git a/pkgs/servers/osmocom/libasn1c/default.nix b/pkgs/by-name/li/libasn1c/package.nix
similarity index 85%
rename from pkgs/servers/osmocom/libasn1c/default.nix
rename to pkgs/by-name/li/libasn1c/package.nix
index 01eb7cf3bd45..941eacf4ea6d 100644
--- a/pkgs/servers/osmocom/libasn1c/default.nix
+++ b/pkgs/by-name/li/libasn1c/package.nix
@@ -7,19 +7,19 @@
   talloc,
 }:
 
-stdenv.mkDerivation rec {
+stdenv.mkDerivation (finalAttrs: {
   pname = "libasn1c";
   version = "0.9.38";
 
   src = fetchFromGitHub {
     owner = "osmocom";
     repo = "libasn1c";
-    rev = version;
+    tag = finalAttrs.version;
     hash = "sha256-cnXcUvP6WwHVvpdsIVsMkizlLyg9KMwVj8XYX/nIfic=";
   };
 
   postPatch = ''
-    echo "${version}" > .tarball-version
+    echo "${finalAttrs.version}" > .tarball-version
   '';
 
   nativeBuildInputs = [
@@ -40,4 +40,4 @@ stdenv.mkDerivation rec {
     platforms = lib.platforms.linux;
     maintainers = [ ];
   };
-}
+})
diff --git a/pkgs/by-name/li/lilypond-unstable/package.nix b/pkgs/by-name/li/lilypond-unstable/package.nix
new file mode 100644
index 000000000000..1fe01def478a
--- /dev/null
+++ b/pkgs/by-name/li/lilypond-unstable/package.nix
@@ -0,0 +1,25 @@
+{
+  lib,
+  fetchzip,
+  lilypond,
+  writeScript,
+}:
+
+lilypond.overrideAttrs (
+  finalAttrs: prevAttrs: {
+    version = "2.25.32";
+
+    src = fetchzip {
+      url = "https://lilypond.org/download/sources/v${lib.versions.majorMinor finalAttrs.version}/lilypond-${finalAttrs.version}.tar.gz";
+      hash = "sha256-j7Avb9WSy27yQCak3KV7OB24M+T76b/tLcLoINLSEbo=";
+    };
+
+    passthru.updateScript = writeScript "update-lilypond-unstable" ''
+      #!/usr/bin/env nix-shell
+      #!nix-shell -i bash -p common-updater-scripts curl
+      version="$(curl -s 'https://gitlab.com/lilypond/lilypond/-/raw/master/VERSION' | grep 'VERSION_DEVEL=' | cut -d= -f2)"
+      update-source-version lilypond-unstable "$version" \
+         --file=pkgs/by-name/li/lilypond-unstable/package.nix
+    '';
+  }
+)
diff --git a/pkgs/misc/lilypond/with-fonts.nix b/pkgs/by-name/li/lilypond-with-fonts/package.nix
similarity index 75%
rename from pkgs/misc/lilypond/with-fonts.nix
rename to pkgs/by-name/li/lilypond-with-fonts/package.nix
index 95bb75318e05..8c4f2c902a89 100644
--- a/pkgs/misc/lilypond/with-fonts.nix
+++ b/pkgs/by-name/li/lilypond-with-fonts/package.nix
@@ -14,7 +14,11 @@ lib.appendToName "with-fonts" (symlinkJoin {
     meta
     ;
 
-  paths = [ lilypond ] ++ openlilylib-fonts.all;
+  paths = [
+    lilypond
+  ]
+  # relevant for lilypond-unstable-with-fonts
+  ++ (openlilylib-fonts.override { inherit lilypond; }).all;
 
   nativeBuildInputs = [ makeWrapper ];
 
diff --git a/pkgs/misc/lilypond/default.nix b/pkgs/by-name/li/lilypond/package.nix
similarity index 84%
rename from pkgs/misc/lilypond/default.nix
rename to pkgs/by-name/li/lilypond/package.nix
index 9bd6351bd2b1..c81b8a6df53d 100644
--- a/pkgs/misc/lilypond/default.nix
+++ b/pkgs/by-name/li/lilypond/package.nix
@@ -40,9 +40,10 @@
       metafont
     ]
   ),
+  writeScript,
 }:
 
-stdenv.mkDerivation rec {
+stdenv.mkDerivation (finalAttrs: {
   pname = "lilypond";
   version = "2.24.4";
   outputs = [
@@ -51,7 +52,7 @@ stdenv.mkDerivation rec {
   ];
 
   src = fetchzip {
-    url = "http://lilypond.org/download/sources/v${lib.versions.majorMinor version}/lilypond-${version}.tar.gz";
+    url = "http://lilypond.org/download/sources/v${lib.versions.majorMinor finalAttrs.version}/lilypond-${finalAttrs.version}.tar.gz";
     hash = "sha256-UYdORvodrVchxslOxpMiXrAh7DtB9sWp9yqZU/jeB9Y=";
   };
 
@@ -120,10 +121,12 @@ stdenv.mkDerivation rec {
 
   enableParallelBuilding = true;
 
-  passthru.updateScript = {
-    command = [ ./update.sh ];
-    supportedFeatures = [ "commit" ];
-  };
+  passthru.updateScript = writeScript "update-lilypond" ''
+    #!/usr/bin/env nix-shell
+    #!nix-shell -i bash -p common-updater-scripts curl
+    version="$(curl -s 'https://gitlab.com/lilypond/lilypond/-/raw/master/VERSION' | grep 'VERSION_STABLE=' | cut -d= -f2)"
+    update-source-version lilypond "$version"
+  '';
 
   # documentation makefile uses "out" for different purposes, hence we explicitly set it to an empty string
   makeFlags = [ "out=" ];
@@ -147,4 +150,4 @@ stdenv.mkDerivation rec {
   FONTCONFIG_FILE = lib.optional stdenv.hostPlatform.isDarwin (makeFontsConf {
     fontDirectories = [ freefont_ttf ];
   });
-}
+})
diff --git a/pkgs/servers/minio/default.nix b/pkgs/by-name/mi/minio/package.nix
similarity index 83%
rename from pkgs/servers/minio/default.nix
rename to pkgs/by-name/mi/minio/package.nix
index 69c99f1ef9e8..199e68f5ff9e 100644
--- a/pkgs/servers/minio/default.nix
+++ b/pkgs/by-name/mi/minio/package.nix
@@ -28,14 +28,14 @@ let
   #   => "2021"
   versionToYear = version: builtins.elemAt (lib.splitString "-" version) 0;
 in
-buildGoModule rec {
+buildGoModule (finalAttrs: {
   pname = "minio";
   version = "2025-10-15T17-29-55Z";
 
   src = fetchFromGitHub {
     owner = "minio";
     repo = "minio";
-    rev = "RELEASE.${version}";
+    rev = "RELEASE.${finalAttrs.version}";
     hash = "sha256-HbjmCJYkWyRRHKriLP6QohaXYLk3QEVfi32Krq3ujjo=";
   };
 
@@ -56,10 +56,10 @@ buildGoModule rec {
     [
       "-s"
       "-w"
-      "-X ${t}.Version=${versionToTimestamp version}"
-      "-X ${t}.CopyrightYear=${versionToYear version}"
-      "-X ${t}.ReleaseTag=RELEASE.${version}"
-      "-X ${t}.CommitID=${src.rev}"
+      "-X ${t}.Version=${versionToTimestamp finalAttrs.version}"
+      "-X ${t}.CopyrightYear=${versionToYear finalAttrs.version}"
+      "-X ${t}.ReleaseTag=RELEASE.${finalAttrs.version}"
+      "-X ${t}.CommitID=${finalAttrs.src.rev}"
     ];
 
   passthru.tests.minio = nixosTests.minio;
@@ -67,7 +67,7 @@ buildGoModule rec {
   meta = {
     homepage = "https://www.minio.io/";
     description = "S3-compatible object storage server";
-    changelog = "https://github.com/minio/minio/releases/tag/RELEASE.${version}";
+    changelog = "https://github.com/minio/minio/releases/tag/RELEASE.${finalAttrs.version}";
     maintainers = with lib.maintainers; [
       bachp
       ryan4yin
@@ -75,4 +75,4 @@ buildGoModule rec {
     license = lib.licenses.agpl3Plus;
     mainProgram = "minio";
   };
-}
+})
diff --git a/pkgs/servers/persistent-evdev/default.nix b/pkgs/by-name/pe/persistent-evdev/package.nix
similarity index 83%
rename from pkgs/servers/persistent-evdev/default.nix
rename to pkgs/by-name/pe/persistent-evdev/package.nix
index d7fd26d134b3..309a2f749980 100644
--- a/pkgs/servers/persistent-evdev/default.nix
+++ b/pkgs/by-name/pe/persistent-evdev/package.nix
@@ -1,25 +1,23 @@
 {
   lib,
-  buildPythonPackage,
+  python3Packages,
   fetchFromGitHub,
-  evdev,
-  pyudev,
   udevCheckHook,
 }:
 
-buildPythonPackage rec {
+python3Packages.buildPythonPackage {
   pname = "persistent-evdev";
   version = "unstable-2022-05-07";
   pyproject = false;
 
   src = fetchFromGitHub {
     owner = "aiberia";
-    repo = pname;
+    repo = "persistent-evdev";
     rev = "52bf246464e09ef4e6f2e1877feccc7b9feba164";
-    sha256 = "d0i6DL/qgDELet4ew2lyVqzd9TApivRxL3zA3dcsQXY=";
+    hash = "sha256-d0i6DL/qgDELet4ew2lyVqzd9TApivRxL3zA3dcsQXY=";
   };
 
-  propagatedBuildInputs = [
+  propagatedBuildInputs = with python3Packages; [
     evdev
     pyudev
   ];
diff --git a/pkgs/servers/polaris/web.nix b/pkgs/by-name/po/polaris-web/package.nix
similarity index 90%
rename from pkgs/servers/polaris/web.nix
rename to pkgs/by-name/po/polaris-web/package.nix
index 6e524bbe18e8..da681f9ae641 100644
--- a/pkgs/servers/polaris/web.nix
+++ b/pkgs/by-name/po/polaris-web/package.nix
@@ -4,14 +4,14 @@
   fetchFromGitHub,
 }:
 
-buildNpmPackage rec {
+buildNpmPackage (finalAttrs: {
   pname = "polaris-web";
   version = "69";
 
   src = fetchFromGitHub {
     owner = "agersant";
     repo = "polaris-web";
-    rev = "build-${version}";
+    tag = "build-${finalAttrs.version}";
     hash = "sha256-/UmAOunc/79DpZByUrzqNA7q7JNugEceKRZvyTGhtVQ=";
   };
 
@@ -36,4 +36,4 @@ buildNpmPackage rec {
     license = lib.licenses.mit;
     maintainers = with lib.maintainers; [ pbsds ];
   };
-}
+})
diff --git a/pkgs/servers/polaris/default.nix b/pkgs/by-name/po/polaris/package.nix
similarity index 93%
rename from pkgs/servers/polaris/default.nix
rename to pkgs/by-name/po/polaris/package.nix
index bd276dbc6dc6..a8d16f86bb9c 100644
--- a/pkgs/servers/polaris/default.nix
+++ b/pkgs/by-name/po/polaris/package.nix
@@ -7,14 +7,14 @@
   nixosTests,
 }:
 
-rustPlatform.buildRustPackage rec {
+rustPlatform.buildRustPackage (finalAttrs: {
   pname = "polaris";
   version = "0.14.3";
 
   src = fetchFromGitHub {
     owner = "agersant";
     repo = "polaris";
-    rev = version;
+    tag = finalAttrs.version;
     hash = "sha256-2GHYIlEzRS7KXahdrxMjyIcPCNw8gXJw5/4ZpB/zT3Y=";
 
     # The polaris version upstream in Cargo.lock is "0.0.0".
@@ -25,7 +25,7 @@ rustPlatform.buildRustPackage rec {
     postFetch = ''
       # 'substituteInPlace' does not support multiline replacements?
       sed -i $out/Cargo.lock -z \
-        -e 's/\[\[package\]\]\nname = "polaris"\nversion = "0.0.0"/[[package]]\nname = "polaris"\nversion = "'"${version}"'"/g'
+        -e 's/\[\[package\]\]\nname = "polaris"\nversion = "0.0.0"/[[package]]\nname = "polaris"\nversion = "'"${finalAttrs.version}"'"/g'
     '';
   };
 
@@ -66,4 +66,4 @@ rustPlatform.buildRustPackage rec {
     platforms = lib.platforms.unix;
     mainProgram = "polaris";
   };
-}
+})
diff --git a/pkgs/servers/xmpp/prosody/default.nix b/pkgs/by-name/pr/prosody/package.nix
similarity index 100%
rename from pkgs/servers/xmpp/prosody/default.nix
rename to pkgs/by-name/pr/prosody/package.nix
diff --git a/pkgs/servers/misc/qremotecontrol-server/0001-fix-qt5-build-include-QDataStream.patch b/pkgs/by-name/qr/qremotecontrol-server/0001-fix-qt5-build-include-QDataStream.patch
similarity index 100%
rename from pkgs/servers/misc/qremotecontrol-server/0001-fix-qt5-build-include-QDataStream.patch
rename to pkgs/by-name/qr/qremotecontrol-server/0001-fix-qt5-build-include-QDataStream.patch
diff --git a/pkgs/servers/misc/qremotecontrol-server/default.nix b/pkgs/by-name/qr/qremotecontrol-server/package.nix
similarity index 95%
rename from pkgs/servers/misc/qremotecontrol-server/default.nix
rename to pkgs/by-name/qr/qremotecontrol-server/package.nix
index 0c4a5a1c60ef..9b8c48641ec7 100644
--- a/pkgs/servers/misc/qremotecontrol-server/default.nix
+++ b/pkgs/by-name/qr/qremotecontrol-server/package.nix
@@ -2,9 +2,7 @@
   lib,
   stdenv,
   fetchgit,
-  qmake,
-  wrapQtAppsHook,
-  qtbase,
+  qt5,
   libxtst,
 }:
 
@@ -23,12 +21,12 @@ stdenv.mkDerivation {
   ];
 
   nativeBuildInputs = [
-    qmake
-    wrapQtAppsHook
+    qt5.qmake
+    qt5.wrapQtAppsHook
   ];
 
   buildInputs = [
-    qtbase
+    qt5.qtbase
     libxtst
   ];
 
diff --git a/pkgs/servers/shairplay/default.nix b/pkgs/by-name/sh/shairplay/package.nix
similarity index 82%
rename from pkgs/servers/shairplay/default.nix
rename to pkgs/by-name/sh/shairplay/package.nix
index d7eb009476ac..560bf9964fe1 100644
--- a/pkgs/servers/shairplay/default.nix
+++ b/pkgs/by-name/sh/shairplay/package.nix
@@ -4,11 +4,11 @@
   fetchFromGitHub,
   autoreconfHook,
   pkg-config,
-  avahi,
+  avahi-compat,
   libao,
 }:
 
-stdenv.mkDerivation rec {
+stdenv.mkDerivation (finalAttrs: {
   pname = "shairplay-unstable";
   version = "2018-08-24";
 
@@ -25,7 +25,7 @@ stdenv.mkDerivation rec {
   ];
 
   buildInputs = [
-    avahi
+    avahi-compat
     libao
   ];
 
@@ -34,16 +34,16 @@ stdenv.mkDerivation rec {
   # the build will fail without complaining about a reference to /tmp
   preFixup = lib.optionalString stdenv.hostPlatform.isLinux ''
     patchelf \
-      --set-rpath "${lib.makeLibraryPath buildInputs}:$out/lib" \
+      --set-rpath "${lib.makeLibraryPath finalAttrs.buildInputs}:$out/lib" \
       $out/bin/shairplay
   '';
 
   meta = {
-    inherit (src.meta) homepage;
+    inherit (finalAttrs.src.meta) homepage;
     description = "Apple AirPlay and RAOP protocol server";
     license = lib.licenses.mit;
     maintainers = with lib.maintainers; [ peterhoeg ];
     platforms = lib.platforms.unix;
     mainProgram = "shairplay";
   };
-}
+})
diff --git a/pkgs/servers/shishi/default.nix b/pkgs/by-name/sh/shishi/package.nix
similarity index 64%
rename from pkgs/servers/shishi/default.nix
rename to pkgs/by-name/sh/shishi/package.nix
index 79551bfde1ce..71b3c96b2477 100644
--- a/pkgs/servers/shishi/default.nix
+++ b/pkgs/by-name/sh/shishi/package.nix
@@ -8,27 +8,23 @@
   libtasn1,
 
   # Optional Dependencies
-  pam ? null,
-  libidn ? null,
-  gnutls ? null,
+  usePam ? lib.meta.availableOn stdenv.hostPlatform pam && stdenv.hostPlatform.isLinux,
+  pam,
+  useLibidn ? lib.meta.availableOn stdenv.hostPlatform libidn,
+  libidn,
+  useGnutls ? lib.meta.availableOn stdenv.hostPlatform gnutls,
+  gnutls,
 }:
 
 let
-  shouldUsePkg =
-    pkg: if pkg != null && lib.meta.availableOn stdenv.hostPlatform pkg then pkg else null;
-
-  optPam = shouldUsePkg pam;
-  optLibidn = shouldUsePkg libidn;
-  optGnutls = shouldUsePkg gnutls;
-
   inherit (lib) enableFeature withFeature optionalString;
 in
-stdenv.mkDerivation rec {
+stdenv.mkDerivation (finalAttrs: {
   pname = "shishi";
   version = "1.0.3";
 
   src = fetchurl {
-    url = "mirror://gnu/shishi/shishi-${version}.tar.gz";
+    url = "mirror://gnu/shishi/shishi-${finalAttrs.version}.tar.gz";
     hash = "sha256-lXmP/RLdAaT4jgMR7gPKSibly05ekFmkDk/E2fKRfpI=";
   };
 
@@ -39,19 +35,20 @@ stdenv.mkDerivation rec {
     libgcrypt
     libgpg-error
     libtasn1
-    optPam
-    optLibidn
-    optGnutls
+    # TODO use lib.optional instead of setting packages to null
+    (if usePam then pam else null)
+    (if useLibidn then libidn else null)
+    (if useGnutls then gnutls else null)
   ];
 
   configureFlags = [
     "--sysconfdir=/etc"
     "--localstatedir=/var"
     (enableFeature true "libgcrypt")
-    (enableFeature (optPam != null) "pam")
+    (enableFeature usePam "pam")
     (enableFeature true "ipv6")
-    (withFeature (optLibidn != null) "stringprep")
-    (enableFeature (optGnutls != null) "starttls")
+    (withFeature useLibidn "stringprep")
+    (enableFeature useGnutls "starttls")
     (enableFeature true "des")
     (enableFeature true "3des")
     (enableFeature true "aes")
@@ -70,11 +67,11 @@ stdenv.mkDerivation rec {
   postInstall = ''
     sed -i $out/lib/libshi{sa,shi}.la \
   ''
-  + optionalString (optLibidn != null) ''
-    -e 's,\(-lidn\),-L${optLibidn.out}/lib \1,' \
+  + optionalString useLibidn ''
+    -e 's,\(-lidn\),-L${libidn.out}/lib \1,' \
   ''
-  + optionalString (optGnutls != null) ''
-    -e 's,\(-lgnutls\),-L${optGnutls.out}/lib \1,' \
+  + optionalString useGnutls ''
+    -e 's,\(-lgnutls\),-L${gnutls.out}/lib \1,' \
   ''
   + ''
     -e 's,\(-lgcrypt\),-L${libgcrypt.out}/lib \1,' \
@@ -89,4 +86,4 @@ stdenv.mkDerivation rec {
     maintainers = with lib.maintainers; [ lovek323 ];
     platforms = lib.platforms.linux;
   };
-}
+})
diff --git a/pkgs/servers/sks/adapt-to-nixos.patch b/pkgs/by-name/sk/sks/adapt-to-nixos.patch
similarity index 100%
rename from pkgs/servers/sks/adapt-to-nixos.patch
rename to pkgs/by-name/sk/sks/adapt-to-nixos.patch
diff --git a/pkgs/servers/sks/default.nix b/pkgs/by-name/sk/sks/package.nix
similarity index 75%
rename from pkgs/servers/sks/default.nix
rename to pkgs/by-name/sk/sks/package.nix
index 910e3b0fad39..add658800aaa 100644
--- a/pkgs/servers/sks/default.nix
+++ b/pkgs/by-name/sk/sks/package.nix
@@ -2,7 +2,8 @@
   lib,
   stdenv,
   fetchFromGitHub,
-  ocamlPackages,
+  pkgsHostHost,
+  ocaml-ng,
   perl,
   zlib,
   db,
@@ -10,7 +11,7 @@
 }:
 
 let
-  inherit (ocamlPackages)
+  inherit (ocaml-ng.ocamlPackages_4_12)
     ocaml
     findlib
     cryptokit
@@ -18,7 +19,7 @@ let
     ;
 in
 
-stdenv.mkDerivation rec {
+stdenv.mkDerivation (finalAttrs: {
   pname = "sks";
   version = "unstable-2021-02-04";
 
@@ -39,11 +40,23 @@ stdenv.mkDerivation rec {
     "webSamples"
   ];
 
-  nativeBuildInputs = [
-    ocaml
-    findlib
-    perl
-  ];
+  nativeBuildInputs =
+    # use static -> static ocaml because dynamic -> static ocaml doesn't compile
+    (
+      if stdenv.hostPlatform.isStatic then
+        [
+          pkgsHostHost.ocaml-ng.ocamlPackages_4_12.ocaml
+          pkgsHostHost.ocaml-ng.ocamlPackages_4_12.findlib
+        ]
+      else
+        [
+          ocaml
+          findlib
+        ]
+    )
+    ++ [
+      perl
+    ];
   buildInputs = [
     zlib
     db
@@ -81,9 +94,9 @@ stdenv.mkDerivation rec {
       servers, and even wildly out-of-date servers, or servers that experience
       spotty connectivity, can fully synchronize with rest of the system.
     '';
-    inherit (src.meta) homepage;
+    inherit (finalAttrs.src.meta) homepage;
     license = lib.licenses.gpl2Plus;
     platforms = lib.platforms.linux;
     maintainers = [ ];
   };
-}
+})
diff --git a/pkgs/servers/tang/default.nix b/pkgs/by-name/ta/tang/package.nix
similarity index 88%
rename from pkgs/servers/tang/default.nix
rename to pkgs/by-name/ta/tang/package.nix
index 76b95aa942e8..97deec22126b 100644
--- a/pkgs/servers/tang/default.nix
+++ b/pkgs/by-name/ta/tang/package.nix
@@ -3,7 +3,7 @@
   stdenv,
   fetchFromGitHub,
   pkg-config,
-  asciidoc,
+  asciidoc-full,
   jansson,
   jose,
   http-parser,
@@ -17,19 +17,19 @@
   nixosTests,
 }:
 
-stdenv.mkDerivation rec {
+stdenv.mkDerivation (finalAttrs: {
   pname = "tang";
   version = "15";
 
   src = fetchFromGitHub {
     owner = "latchset";
     repo = "tang";
-    tag = "v${version}";
+    tag = "v${finalAttrs.version}";
     hash = "sha256-nlC2hdNzQZrfirjS2gX4oFp2OD1OdxmLsN03hfxD3ug=";
   };
 
   nativeBuildInputs = [
-    asciidoc
+    asciidoc-full
     meson
     ninja
     pkg-config
@@ -60,7 +60,7 @@ stdenv.mkDerivation rec {
       version = testers.testVersion {
         package = tang;
         command = "${tang}/libexec/tangd --version";
-        version = "tangd ${version}";
+        version = "tangd ${finalAttrs.version}";
       };
     };
     updateScript = gitUpdater { };
@@ -69,9 +69,9 @@ stdenv.mkDerivation rec {
   meta = {
     description = "Server for binding data to network presence";
     homepage = "https://github.com/latchset/tang";
-    changelog = "https://github.com/latchset/tang/releases/tag/v${version}";
+    changelog = "https://github.com/latchset/tang/releases/tag/v${finalAttrs.version}";
     maintainers = with lib.maintainers; [ fpletz ];
     license = lib.licenses.gpl3Plus;
     mainProgram = "tangd";
   };
-}
+})
diff --git a/pkgs/servers/tautulli/default.nix b/pkgs/by-name/ta/tautulli/package.nix
similarity index 83%
rename from pkgs/servers/tautulli/default.nix
rename to pkgs/by-name/ta/tautulli/package.nix
index 4154d066d06a..55785b012d11 100644
--- a/pkgs/servers/tautulli/default.nix
+++ b/pkgs/by-name/ta/tautulli/package.nix
@@ -1,27 +1,25 @@
 {
   lib,
   fetchFromGitHub,
-  buildPythonApplication,
-  setuptools,
-  wrapPython,
+  python3Packages,
   makeWrapper,
 }:
 
-buildPythonApplication rec {
+python3Packages.buildPythonApplication (finalAttrs: {
   pname = "Tautulli";
   version = "2.16.1";
   pyproject = false;
 
-  pythonPath = [ setuptools ];
+  pythonPath = [ python3Packages.setuptools ];
   nativeBuildInputs = [
-    wrapPython
+    python3Packages.wrapPython
     makeWrapper
   ];
 
   src = fetchFromGitHub {
     owner = "Tautulli";
     repo = "Tautulli";
-    tag = "v${version}";
+    tag = "v${finalAttrs.version}";
     sha256 = "sha256-Zct7EhnU5LROO23Joz6OxQTtC9uGZhtceSG+aX6MI2c=";
   };
 
@@ -32,7 +30,7 @@ buildPythonApplication rec {
     cp -R contrib data lib plexpy Tautulli.py CHANGELOG.md $out/libexec/tautulli
 
     echo "master" > $out/libexec/tautulli/branch.txt
-    echo "v${version}" > $out/libexec/tautulli/version.txt
+    echo "v${finalAttrs.version}" > $out/libexec/tautulli/version.txt
 
     # Can't just symlink to the main script, since it uses __file__ to
     # import bundled packages and manage the service
@@ -60,4 +58,4 @@ buildPythonApplication rec {
     platforms = lib.platforms.linux;
     maintainers = with lib.maintainers; [ rhoriguchi ];
   };
-}
+})
diff --git a/pkgs/misc/lilypond/unstable.nix b/pkgs/misc/lilypond/unstable.nix
deleted file mode 100644
index 2e81140eb681..000000000000
--- a/pkgs/misc/lilypond/unstable.nix
+++ /dev/null
@@ -1,21 +0,0 @@
-{
-  lib,
-  fetchzip,
-  lilypond,
-}:
-
-lilypond.overrideAttrs (oldAttrs: rec {
-  version = "2.25.32";
-  src = fetchzip {
-    url = "https://lilypond.org/download/sources/v${lib.versions.majorMinor version}/lilypond-${version}.tar.gz";
-    hash = "sha256-j7Avb9WSy27yQCak3KV7OB24M+T76b/tLcLoINLSEbo=";
-  };
-
-  passthru.updateScript = {
-    command = [
-      ./update.sh
-      "unstable"
-    ];
-    supportedFeatures = [ "commit" ];
-  };
-})
diff --git a/pkgs/misc/lilypond/update.sh b/pkgs/misc/lilypond/update.sh
deleted file mode 100755
index 5d5f855dbd7c..000000000000
--- a/pkgs/misc/lilypond/update.sh
+++ /dev/null
@@ -1,25 +0,0 @@
-#!/usr/bin/env nix-shell
-#!nix-shell -I nixpkgs=./. -i bash -p curl gnused nix
-
-set -euo pipefail
-
-if [ $# -gt 0 ] && [ "$1" = "unstable" ]; then
-    ATTR="lilypond-unstable"
-    FILE="$(dirname "${BASH_SOURCE[@]}")/unstable.nix"
-    QUERY="VERSION_DEVEL="
-else
-    ATTR="lilypond"
-    FILE="$(dirname "${BASH_SOURCE[@]}")/default.nix"
-    QUERY="VERSION_STABLE="
-fi
-
-# update version
-PREV=$(nix eval --raw -f default.nix $ATTR.version)
-NEXT=$(curl -s 'https://gitlab.com/lilypond/lilypond/-/raw/master/VERSION' | grep "$QUERY" | cut -d= -f2)
-sed -i "s|$PREV|$NEXT|" "$FILE"
-echo "[{\"commitMessage\":\"$ATTR: $PREV -> $NEXT\"}]"
-
-# update hash
-PREV=$(nix eval --raw -f default.nix $ATTR.src.outputHash)
-NEXT=$(nix --extra-experimental-features nix-command hash to-sri --type sha256 $(nix-prefetch-url --type sha256 --unpack $(nix eval --raw -f default.nix $ATTR.src.url)))
-sed -i "s|$PREV|$NEXT|" "$FILE"
diff --git a/pkgs/servers/jackett/updater.sh b/pkgs/servers/jackett/updater.sh
deleted file mode 100755
index 1714565edd49..000000000000
--- a/pkgs/servers/jackett/updater.sh
+++ /dev/null
@@ -1,16 +0,0 @@
-#!/usr/bin/env nix-shell
-#!nix-shell -I nixpkgs=./. -i bash -p curl jq common-updater-scripts
-set -eo pipefail
-cd "$(dirname "${BASH_SOURCE[0]}")"
-
-new_version="$(curl -s "https://api.github.com/repos/jackett/jackett/releases?per_page=1" | jq -r '.[0].name')"
-old_version="$(sed -nE 's/\s*version = "(.*)".*/\1/p' ./default.nix)"
-
-if [[ "$new_version" == "$old_version" ]]; then
-  echo "Already up to date!"
-  exit 0
-fi
-
-cd ../../..
-update-source-version jackett "${new_version//v}"
-$(nix-build -A jackett.fetch-deps --no-out-link)
diff --git a/pkgs/top-level/all-packages.nix b/pkgs/top-level/all-packages.nix
index fbc504abb334..70ef90e6905b 100644
--- a/pkgs/top-level/all-packages.nix
+++ b/pkgs/top-level/all-packages.nix
@@ -2039,8 +2039,6 @@ with pkgs;
 
   unify = with python3Packages; toPythonApplication unify;
 
-  persistent-evdev = python3Packages.callPackage ../servers/persistent-evdev { };
-
   inherit (import ../development/libraries/libsbsms pkgs)
     libsbsms
     libsbsms_2_0_2
@@ -2684,8 +2682,6 @@ with pkgs;
     isl_0_27
     ;
 
-  jackett = callPackage ../servers/jackett { };
-
   jamesdsp-pulse = callPackage ../by-name/ja/jamesdsp/package.nix {
     usePipewire = false;
     usePulseaudio = true;
@@ -3291,8 +3287,6 @@ with pkgs;
 
   tabview = with python3Packages; toPythonApplication tabview;
 
-  tautulli = python3Packages.callPackage ../servers/tautulli { };
-
   inherit (callPackage ../development/tools/pnpm { })
     pnpm_8
     pnpm_9
@@ -3307,10 +3301,6 @@ with pkgs;
 
   po4a = perlPackages.Po4a;
 
-  polaris = callPackage ../servers/polaris { };
-
-  polaris-web = callPackage ../servers/polaris/web.nix { };
-
   proxmark3 = libsForQt5.callPackage ../tools/security/proxmark3/default.nix { };
 
   pycflow2dot = with python3.pkgs; toPythonApplication pycflow2dot;
@@ -3436,10 +3426,6 @@ with pkgs;
   # aka., pgp-tools
   simplescreenrecorder = libsForQt5.callPackage ../applications/video/simplescreenrecorder { };
 
-  sks = callPackage ../servers/sks {
-    ocamlPackages = ocaml-ng.ocamlPackages_4_12;
-  };
-
   snapcast = callPackage ../applications/audio/snapcast {
     pulseaudioSupport = config.pulseaudio or stdenv.hostPlatform.isLinux;
   };
@@ -6734,10 +6720,6 @@ with pkgs;
     '';
   });
 
-  isso = callPackage ../servers/isso {
-    nodejs = nodejs_20;
-  };
-
   itk_5_2 = callPackage ../development/libraries/itk/5.2.x.nix {
     enableRtk = false;
   };
@@ -6760,7 +6742,6 @@ with pkgs;
 
   libappindicator-gtk2 = libappindicator.override { gtkVersion = "2"; };
   libappindicator-gtk3 = libappindicator.override { gtkVersion = "3"; };
-  libasn1c = callPackage ../servers/osmocom/libasn1c/default.nix { };
 
   libbass = (callPackage ../development/libraries/audio/libbass { }).bass;
   libbass_fx = (callPackage ../development/libraries/audio/libbass { }).bass_fx;
@@ -8200,8 +8181,6 @@ with pkgs;
     erlang = beamMinimalPackages.erlang;
   };
 
-  dcnnt = python3Packages.callPackage ../servers/dcnnt { };
-
   dict = callPackage ../servers/dict {
     flex = flex_2_5_35;
     libmaa = callPackage ../servers/dict/libmaa.nix { };
@@ -8213,11 +8192,6 @@ with pkgs;
 
   dodgy = with python3Packages; toPythonApplication dodgy;
 
-  prosody = callPackage ../servers/xmpp/prosody {
-    withExtraLibs = [ ];
-    withExtraLuaPackages = _: [ ];
-  };
-
   inherit (callPackages ../servers/firebird { })
     firebird_4
     firebird_3
@@ -8342,8 +8316,6 @@ with pkgs;
     ];
   };
 
-  minio = callPackage ../servers/minio { };
-
   mkchromecast = libsForQt5.callPackage ../applications/networking/mkchromecast { };
 
   moodle = callPackage ../servers/web-apps/moodle { };
@@ -8519,10 +8491,6 @@ with pkgs;
     msVarsTemplate = stdenv.hostPlatform.isx86_64 || stdenv.hostPlatform.isAarch64;
   };
 
-  tang = callPackage ../servers/tang {
-    asciidoc = asciidoc-full;
-  };
-
   inherit (import ../servers/sql/postgresql pkgs)
     postgresqlVersions
     postgresqlJitVersions
@@ -8667,8 +8635,6 @@ with pkgs;
 
   pypiserver = with python3Packages; toPythonApplication pypiserver;
 
-  qremotecontrol-server = libsForQt5.callPackage ../servers/misc/qremotecontrol-server { };
-
   rethinkdb = callPackage ../servers/nosql/rethinkdb {
     stdenv = clangStdenv;
     libtool = cctools;
@@ -8694,8 +8660,6 @@ with pkgs;
 
   scalene = with python3Packages; toPythonApplication scalene;
 
-  shairplay = callPackage ../servers/shairplay { avahi = avahi-compat; };
-
   shairport-sync-airplay2 = shairport-sync.override {
     enableAirplay2 = true;
   };
@@ -8713,11 +8677,6 @@ with pkgs;
     sensu-go-cli
     ;
 
-  shishi = callPackage ../servers/shishi {
-    pam = if stdenv.hostPlatform.isLinux then pam else null;
-    # see also openssl, which has/had this same trick
-  };
-
   spacecookie = haskell.lib.compose.justStaticExecutables haskellPackages.spacecookie;
 
   inherit (callPackages ../servers/http/tomcat { })
@@ -9316,11 +9275,7 @@ with pkgs;
 
   ### DATA
 
-  adwaita-qt = libsForQt5.callPackage ../data/themes/adwaita-qt { };
-
-  adwaita-qt6 = qt6Packages.callPackage ../data/themes/adwaita-qt {
-    useQt6 = true;
-  };
+  adwaita-qt6 = adwaita-qt.override { useQt6 = true; };
 
   dejavu_fonts = lowPrio (callPackage ../data/fonts/dejavu-fonts { });
 
@@ -12416,19 +12371,10 @@ with pkgs;
     ;
   kops = kops_1_33;
 
-  lilypond = callPackage ../misc/lilypond { };
-
-  lilypond-unstable = callPackage ../misc/lilypond/unstable.nix { };
-
-  lilypond-unstable-with-fonts = callPackage ../misc/lilypond/with-fonts.nix {
+  lilypond-unstable-with-fonts = lilypond-with-fonts.override {
     lilypond = lilypond-unstable;
-    openlilylib-fonts = openlilylib-fonts.override {
-      lilypond = lilypond-unstable;
-    };
   };
 
-  lilypond-with-fonts = callPackage ../misc/lilypond/with-fonts.nix { };
-
   openlilylib-fonts = recurseIntoAttrs (callPackage ../misc/lilypond/fonts.nix { });
 
   nixDependencies = recurseIntoAttrs (