actually, it works from cross-pkgs

crossenv/flake.nix

@@ -52,8 +52,7 @@
           cross-pkgs.libffi
 
           # expose openssl header and library for python-cryptography build.
-          # It seems wrong that this is from native-pkgs, so maybe it is.
-          native-pkgs.openssl_1_1
+          cross-pkgs.openssl_1_1
 
           # expose a native rust toolchain so we can build the rust-based
           # Python extensions