7 files changed, 45 insertions, 3 deletions
diff --git a/doc/languages-frameworks/python.section.md b/doc/languages-frameworks/python.section.md
index 7df8464917cf..7fb8ba2e7c27 100644
--- a/doc/languages-frameworks/python.section.md
+++ b/doc/languages-frameworks/python.section.md
@@ -1664,6 +1664,26 @@ self: super: {
 }
 ```
 
+### How to override a Python package for all Python versions using extensions? {#how-to-override-a-python-package-for-all-python-versions-using-extensions}
+
+The following overlay overrides the call to `buildPythonPackage` for the
+`foo` package for all interpreters by appending a Python extension to the
+`pythonPackagesExtensions` list of extensions.
+
+```nix
+final: prev: {
+  pythonPackagesExtensions = prev.pythonPackagesExtensions ++ [
+    (
+      python-final: python-prev: {
+        foo = python-prev.foo.overridePythonAttrs (oldAttrs: {
+          ...
+        });
+      }
+    )
+  ];
+}
+```
+
 ### How to use Intel’s MKL with numpy and scipy? {#how-to-use-intels-mkl-with-numpy-and-scipy}
 
 MKL can be configured using an overlay. See the section "[Using overlays to
diff --git a/pkgs/development/interpreters/python/cpython/2.7/default.nix b/pkgs/development/interpreters/python/cpython/2.7/default.nix
index fd7e684113e7..25446f5fca89 100644
--- a/pkgs/development/interpreters/python/cpython/2.7/default.nix
+++ b/pkgs/development/interpreters/python/cpython/2.7/default.nix
@@ -68,7 +68,7 @@ let
     executable = libPrefix;
     pythonVersion = with sourceVersion; "${major}.${minor}";
     sitePackages = "lib/${libPrefix}/site-packages";
-    inherit hasDistutilsCxxPatch;
+    inherit hasDistutilsCxxPatch pythonAttr;
     pythonOnBuildForBuild = pkgsBuildBuild.${pythonAttr};
     pythonOnBuildForHost = pkgsBuildHost.${pythonAttr};
     pythonOnBuildForTarget = pkgsBuildTarget.${pythonAttr};
diff --git a/pkgs/development/interpreters/python/cpython/default.nix b/pkgs/development/interpreters/python/cpython/default.nix
index a52935c69dfd..dca7d9bb0db5 100644
--- a/pkgs/development/interpreters/python/cpython/default.nix
+++ b/pkgs/development/interpreters/python/cpython/default.nix
@@ -91,7 +91,7 @@ let
     executable = libPrefix;
     pythonVersion = with sourceVersion; "${major}.${minor}";
     sitePackages = "lib/${libPrefix}/site-packages";
-    inherit hasDistutilsCxxPatch;
+    inherit hasDistutilsCxxPatch pythonAttr;
     pythonOnBuildForBuild = override pkgsBuildBuild.${pythonAttr};
     pythonOnBuildForHost = override pkgsBuildHost.${pythonAttr};
     pythonOnBuildForTarget = override pkgsBuildTarget.${pythonAttr};
diff --git a/pkgs/development/interpreters/python/default.nix b/pkgs/development/interpreters/python/default.nix
index 5593158e7f36..471f96b51887 100644
--- a/pkgs/development/interpreters/python/default.nix
+++ b/pkgs/development/interpreters/python/default.nix
@@ -19,9 +19,14 @@ with pkgs;
     , pythonOnBuildForTarget
     , pythonOnHostForHost
     , pythonOnTargetForTarget
+    , pythonAttr ? null
     , self # is pythonOnHostForTarget
     }: let
       pythonPackages = callPackage
+        # Function that when called
+        # - imports python-packages.nix
+        # - adds spliced package sets to the package set
+        # - applies overrides from `packageOverrides` and `pythonPackagesOverlays`.
         ({ pkgs, stdenv, python, overrides }: let
           pythonPackagesFun = import ../../../top-level/python-packages.nix {
             inherit stdenv pkgs lib;
@@ -74,7 +79,7 @@ with pkgs;
           extra = _: {};
           optionalExtensions = cond: as: if cond then as else [];
           python2Extension = import ../../../top-level/python2-packages.nix;
-          extensions = lib.composeManyExtensions ((optionalExtensions (!self.isPy3k) [python2Extension]) ++ [ overrides ]);
+          extensions = lib.composeManyExtensions ((optionalExtensions (!self.isPy3k) [python2Extension]) ++ pkgs.pythonPackagesExtensions ++ [ overrides ]);
           aliases = self: super: lib.optionalAttrs config.allowAliases (import ../../../top-level/python-aliases.nix lib self super);
         in lib.makeScopeWithSplicing
           pkgs.splicePackages
@@ -117,6 +122,8 @@ with pkgs;
         tests = callPackage ./tests.nix {
           python = self;
         };
+
+        inherit pythonAttr;
   };
 
   sources = {
diff --git a/pkgs/development/interpreters/python/pypy/default.nix b/pkgs/development/interpreters/python/pypy/default.nix
index 668a4e24b39e..e8c7d3ba65e5 100644
--- a/pkgs/development/interpreters/python/pypy/default.nix
+++ b/pkgs/development/interpreters/python/pypy/default.nix
@@ -30,6 +30,7 @@ let
     executable = "pypy${if isPy3k then "3" else ""}";
     sitePackages = "site-packages";
     hasDistutilsCxxPatch = false;
+    inherit pythonAttr;
 
     pythonOnBuildForBuild = pkgsBuildBuild.${pythonAttr};
     pythonOnBuildForHost = pkgsBuildHost.${pythonAttr};
diff --git a/pkgs/development/interpreters/python/tests.nix b/pkgs/development/interpreters/python/tests.nix
index 49dfe0e4644e..037c8f87b8ba 100644
--- a/pkgs/development/interpreters/python/tests.nix
+++ b/pkgs/development/interpreters/python/tests.nix
@@ -11,6 +11,7 @@
 , substituteAll
 , lib
 , callPackage
+, pkgs
 }:
 
 let
@@ -133,6 +134,17 @@ let
     # test-overrideScope = let
     #  myPackages = python.pkgs.overrideScope extension;
     # in assert myPackages.foobar == myPackages.numpy; myPackages.python.withPackages(ps: with ps; [ foobar ]);
+  } // lib.optionalAttrs (python ? pythonAttr) {
+    # Test applying overrides using pythonPackagesOverlays.
+    test-pythonPackagesExtensions = let
+      pkgs_ = pkgs.extend(final: prev: {
+        pythonPackagesExtensions = prev.pythonPackagesExtensions ++ [
+          (python-final: python-prev: {
+            foo = python-prev.setuptools;
+          })
+        ];
+      });
+    in pkgs_.${python.pythonAttr}.pkgs.foo;
   };
 
   condaTests = let
diff --git a/pkgs/top-level/all-packages.nix b/pkgs/top-level/all-packages.nix
index e218ce7abb52..996390d070d0 100644
--- a/pkgs/top-level/all-packages.nix
+++ b/pkgs/top-level/all-packages.nix
@@ -14924,6 +14924,8 @@ with pkgs;
   pythonInterpreters = callPackage ./../development/interpreters/python { };
   inherit (pythonInterpreters) python27 python37 python38 python39 python310 python311 python3Minimal pypy27 pypy38 pypy37 rustpython;
 
+  # List of extensions with overrides to apply to all Python package sets.
+  pythonPackagesExtensions = [ ];
   # Python package sets.
   python27Packages = python27.pkgs;
   python37Packages = python37.pkgs;