diff --git a/pkgs/by-name/om/omnissa-horizon-client/package.nix b/pkgs/by-name/om/omnissa-horizon-client/package.nix
index f33afecb0e96..5521d5bebcec 100644
--- a/pkgs/by-name/om/omnissa-horizon-client/package.nix
+++ b/pkgs/by-name/om/omnissa-horizon-client/package.nix
@@ -114,22 +114,7 @@ let
           xorg.libXScrnSaver
           xorg.libXtst
           zlib
-
-          # c.f. https://github.com/NixOS/nixpkgs/pull/418543
-          (libxml2.overrideAttrs (oldAttrs: rec {
-            version = "2.13.8";
-            src = fetchurl {
-              url = "mirror://gnome/sources/libxml2/${lib.versions.majorMinor version}/libxml2-${version}.tar.xz";
-              hash = "sha256-J3KUyzMRmrcbK8gfL0Rem8lDW4k60VuyzSsOhZoO6Eo=";
-            };
-            meta = oldAttrs.meta // {
-              knownVulnerabilities = oldAttrs.meta.knownVulnerabilities or [ ] ++ [
-                "CVE-2025-49794"
-                "CVE-2025-49796"
-                "CVE-2025-6021"
-              ];
-            };
-          }))
+          libxml2_13
 
           (writeTextDir "etc/omnissa/config" configText)
         ];
diff --git a/pkgs/development/python-modules/cwlformat/default.nix b/pkgs/development/python-modules/cwlformat/default.nix
index f9a56ad49870..1144d815b03b 100644
--- a/pkgs/development/python-modules/cwlformat/default.nix
+++ b/pkgs/development/python-modules/cwlformat/default.nix
@@ -6,12 +6,13 @@
   pytestCheckHook,
   pythonOlder,
   ruamel-yaml,
+  setuptools,
 }:
 
 buildPythonPackage rec {
   pname = "cwlformat";
   version = "2022.02.18";
-  format = "setuptools";
+  pyproject = true;
 
   disabled = pythonOlder "3.8";
 
@@ -31,12 +32,19 @@ buildPythonPackage rec {
     })
   ];
 
-  propagatedBuildInputs = [ ruamel-yaml ];
+  build-system = [ setuptools ];
+
+  dependencies = [ ruamel-yaml ];
 
   nativeCheckInputs = [ pytestCheckHook ];
 
   pythonImportsCheck = [ "cwlformat" ];
 
+  disabledTests = [
+    # Test compares output
+    "test_formatting_battery"
+  ];
+
   meta = with lib; {
     description = "Code formatter for CWL";
     homepage = "https://github.com/rabix/cwl-format";
diff --git a/pkgs/development/python-modules/cymruwhois/default.nix b/pkgs/development/python-modules/cymruwhois/default.nix
index 070dc04cb0d4..5bca7d20f923 100644
--- a/pkgs/development/python-modules/cymruwhois/default.nix
+++ b/pkgs/development/python-modules/cymruwhois/default.nix
@@ -33,12 +33,15 @@ buildPythonPackage rec {
   pythonImportsCheck = [ "cymruwhois" ];
 
   disabledTests = [
-    # Tests require network access
-    "test_asn"
     # AssertionError
     "test_doctest"
   ];
 
+  disabledTestPaths = [
+    # £Failed: 'yield' keyword is allowed in fixtures, but not in tests (test_common)
+    "tests/test_common_lookups.py"
+  ];
+
   meta = {
     description = "Python client for the whois.cymru.com service";
     homepage = "https://github.com/JustinAzoff/python-cymruwhois";
diff --git a/pkgs/development/python-modules/fugashi/default.nix b/pkgs/development/python-modules/fugashi/default.nix
index d2d60b3e8143..b2e5997ace6b 100644
--- a/pkgs/development/python-modules/fugashi/default.nix
+++ b/pkgs/development/python-modules/fugashi/default.nix
@@ -1,7 +1,6 @@
 {
   lib,
   fetchFromGitHub,
-  pythonOlder,
   pytestCheckHook,
   buildPythonPackage,
   cython,
@@ -15,8 +14,7 @@
 buildPythonPackage rec {
   pname = "fugashi";
   version = "1.5.1";
-  format = "pyproject";
-  disabled = pythonOlder "3.9";
+  pyproject = true;
 
   src = fetchFromGitHub {
     owner = "polm";
@@ -25,7 +23,12 @@ buildPythonPackage rec {
     hash = "sha256-rkQskRz7lgVBrqBeyj9kWO2/7POrZ0TaM+Z7mhpZLvM=";
   };
 
-  nativeBuildInputs = [
+  postPatch = ''
+    substituteInPlace pyproject.toml \
+      --replace-fail "Cython~=3.0.11" "Cython"
+  '';
+
+  build-system = [
     cython
     mecab
     setuptools-scm
@@ -51,7 +54,7 @@ buildPythonPackage rec {
   meta = with lib; {
     description = "Cython MeCab wrapper for fast, pythonic Japanese tokenization and morphological analysis";
     homepage = "https://github.com/polm/fugashi";
-    changelog = "https://github.com/polm/fugashi/releases/tag/${version}";
+    changelog = "https://github.com/polm/fugashi/releases/tag/${src.tag}";
     license = licenses.mit;
     maintainers = with maintainers; [ laurent-f1z1 ];
   };
diff --git a/pkgs/development/python-modules/html2image/default.nix b/pkgs/development/python-modules/html2image/default.nix
index bca718a33311..b6990aa5ca9a 100644
--- a/pkgs/development/python-modules/html2image/default.nix
+++ b/pkgs/development/python-modules/html2image/default.nix
@@ -2,7 +2,7 @@
   lib,
   buildPythonPackage,
   fetchFromGitHub,
-  poetry-core,
+  hatchling,
   requests,
   websocket-client,
 }:
@@ -19,13 +19,7 @@ buildPythonPackage rec {
     hash = "sha256-qGp6i4fNmduTZfdxNvYJTAQV/Ovm3XFNOJ8uSj6Ipic=";
   };
 
-  postPatch = ''
-    substituteInPlace pyproject.toml \
-    --replace-fail poetry.masonry.api poetry.core.masonry.api \
-    --replace-fail "poetry>=" "poetry-core>="
-  '';
-
-  build-system = [ poetry-core ];
+  build-system = [ hatchling ];
 
   dependencies = [
     requests
diff --git a/pkgs/development/python-modules/nocaselist/default.nix b/pkgs/development/python-modules/nocaselist/default.nix
index c76216939c54..891b78487ca2 100644
--- a/pkgs/development/python-modules/nocaselist/default.nix
+++ b/pkgs/development/python-modules/nocaselist/default.nix
@@ -5,6 +5,7 @@
   pytestCheckHook,
   pythonOlder,
   setuptools,
+  setuptools-scm,
   six,
 }:
 
@@ -20,7 +21,10 @@ buildPythonPackage rec {
     hash = "sha256-+3MG9aPgRVNOc3q37L7uA5ul6br7xbXyMfYW1+khG2U=";
   };
 
-  build-system = [ setuptools ];
+  build-system = [
+    setuptools
+    setuptools-scm
+  ];
 
   dependencies = [ six ];
 
diff --git a/pkgs/development/python-modules/pytubefix/default.nix b/pkgs/development/python-modules/pytubefix/default.nix
index 45a8742b4e0b..0051f7669298 100644
--- a/pkgs/development/python-modules/pytubefix/default.nix
+++ b/pkgs/development/python-modules/pytubefix/default.nix
@@ -1,5 +1,6 @@
 {
   lib,
+  aiohttp,
   buildPythonPackage,
   fetchFromGitHub,
   setuptools,
@@ -20,6 +21,8 @@ buildPythonPackage rec {
 
   build-system = [ setuptools ];
 
+  dependencies = [ aiohttp ];
+
   nativeCheckInputs = [ pytestCheckHook ];
 
   disabledTestPaths = [
diff --git a/pkgs/development/python-modules/schema-salad/default.nix b/pkgs/development/python-modules/schema-salad/default.nix
index 872f8073f0ca..66654564b824 100644
--- a/pkgs/development/python-modules/schema-salad/default.nix
+++ b/pkgs/development/python-modules/schema-salad/default.nix
@@ -36,8 +36,11 @@ buildPythonPackage rec {
   pythonRelaxDeps = [ "mistune" ];
 
   postPatch = ''
+    substituteInPlace setup.py \
+      --replace-fail 'pytest_runner + ["setuptools_scm>=8.0.4,<9"]' '["setuptools_scm"]'
     substituteInPlace pyproject.toml \
-      --replace-fail "mypy[mypyc]==1.15.0" "mypy"
+      --replace-fail '"setuptools_scm[toml]>=8.0.4,<9"' '"setuptools_scm[toml]"' \
+      --replace-fail "mypy[mypyc]==1.17.0" "mypy"
     sed -i "/black>=/d" pyproject.toml
   '';
 
diff --git a/pkgs/development/python-modules/ueberzug/default.nix b/pkgs/development/python-modules/ueberzug/default.nix
index d0169e0f6e39..e10e0b578597 100644
--- a/pkgs/development/python-modules/ueberzug/default.nix
+++ b/pkgs/development/python-modules/ueberzug/default.nix
@@ -1,13 +1,16 @@
 {
   lib,
+  attrs,
   buildPythonPackage,
+  docopt,
   fetchPypi,
-  isPy27,
   libX11,
   libXext,
-  attrs,
-  docopt,
+  libXres,
+  meson-python,
+  meson,
   pillow,
+  pkg-config,
   psutil,
   xlib,
 }:
@@ -15,21 +18,27 @@
 buildPythonPackage rec {
   pname = "ueberzug";
   version = "18.3.1";
-  format = "setuptools";
-
-  disabled = isPy27;
+  pyproject = true;
 
   src = fetchPypi {
     inherit pname version;
-    sha256 = "sha256-1Lk4E5YwEq2mUnYbIWDhzz9/CCwfXMJ11/TtJ44ugOk=";
+    hash = "sha256-1Lk4E5YwEq2mUnYbIWDhzz9/CCwfXMJ11/TtJ44ugOk=";
   };
 
+  build-system = [
+    meson
+    meson-python
+  ];
+
+  nativeBuildInputs = [ pkg-config ];
+
   buildInputs = [
     libX11
+    libXres
     libXext
   ];
 
-  propagatedBuildInputs = [
+  dependencies = [
     attrs
     docopt
     pillow
@@ -42,10 +51,11 @@ buildPythonPackage rec {
   pythonImportsCheck = [ "ueberzug" ];
 
   meta = with lib; {
-    homepage = "https://github.com/seebye/ueberzug";
     description = "Alternative for w3mimgdisplay";
+    homepage = "https://github.com/ueber-devel/ueberzug";
+    changelog = "https://github.com/ueber-devel/ueberzug/releases/tag/${version}";
+    license = licenses.gpl3Only;
     mainProgram = "ueberzug";
-    license = licenses.gpl3;
     maintainers = with maintainers; [ Br1ght0ne ];
   };
 }