diff --git a/pkgs/development/libraries/boost/generic.nix b/pkgs/development/libraries/boost/generic.nix
index b9bdec0cd077..013496a54d5a 100644
--- a/pkgs/development/libraries/boost/generic.nix
+++ b/pkgs/development/libraries/boost/generic.nix
@@ -28,8 +28,6 @@
 # We must build at least one type of libraries
 assert enableShared || enableStatic;
 
-# Python isn't supported when cross-compiling
-assert enablePython -> stdenv.hostPlatform == stdenv.buildPlatform;
 assert enableNumpy -> enablePython;
 
 # Boost <1.69 can't be built on linux with clang >8, because pth was removed
diff --git a/pkgs/development/python-modules/pybind11/default.nix b/pkgs/development/python-modules/pybind11/default.nix
index 8f01ddd49adf..327a44690da3 100644
--- a/pkgs/development/python-modules/pybind11/default.nix
+++ b/pkgs/development/python-modules/pybind11/default.nix
@@ -34,6 +34,7 @@ buildPythonPackage rec {
     "-DBoost_INCLUDE_DIR=${lib.getDev boost}/include"
     "-DEIGEN3_INCLUDE_DIR=${lib.getDev eigen}/include/eigen3"
     "-DBUILD_TESTING=on"
+    "-DPYTHON_EXECUTABLE:FILEPATH=${python.pythonForBuild.interpreter}"
   ] ++ lib.optionals (python.isPy3k && !stdenv.cc.isClang) [
     "-DPYBIND11_CXX_STANDARD=-std=c++17"
   ];