diff --git a/pkgs/development/interpreters/python/mk-python-derivation.nix b/pkgs/development/interpreters/python/mk-python-derivation.nix
index 4917b167046e..963073df6200 100644
--- a/pkgs/development/interpreters/python/mk-python-derivation.nix
+++ b/pkgs/development/interpreters/python/mk-python-derivation.nix
@@ -176,6 +176,8 @@ let
       # default to python's platforms
       platforms = python.meta.platforms;
       isBuildPythonPackage = python.meta.platforms;
+    } // lib.optionalAttrs (attrs?pname) {
+      mainProgram = attrs.pname;
     } // meta;
   } // lib.optionalAttrs (attrs?checkPhase) {
     # If given use the specified checkPhase, otherwise use the setup hook.