diff --git a/python38.changes b/python38.changes
index 0a3236c..eb7a612 100644
--- a/python38.changes
+++ b/python38.changes
@@ -1,3 +1,9 @@
+-------------------------------------------------------------------
+Thu Jul 21 14:19:54 UTC 2022 - Matej Cepl <mcepl@suse.com>
+
+- Switch from %primary_interpreter to prjconf-defined
+  %primary_python (gh#openSUSE/python-rpm-macros#127).
+
 -------------------------------------------------------------------
 Thu May  5 14:34:56 UTC 2022 - Matej Cepl <mcepl@suse.com>
 
diff --git a/python38.spec b/python38.spec
index 12ca381..d656124 100644
--- a/python38.spec
+++ b/python38.spec
@@ -35,6 +35,14 @@
 %bcond_with base
 %bcond_without general
 %endif
+
+%define         python_pkg_name python38
+%if "%{python_pkg_name}" == "%{primary_python}"
+%define primary_interpreter 1
+%else
+%define primary_interpreter 0
+%endif
+
 %define _version %(c=%{version}; echo ${c/[a-z]*/})
 %define tar_suffix %(c=%{_version}; echo ${c#%{_version}})
 %define python_version %(c=%{_version}; echo ${c:0:3})
@@ -48,10 +56,6 @@
 %else
 %define tarversion %{version}
 %endif
-%define         python_pkg_name python38
-# Will provide the python3-* provides
-# Will do the /usr/bin/python3 and all the core links
-%define         primary_interpreter 0
 %define         folderversion %{tarversion}
 %define         tarname    Python-%{tarversion}
 %define         sitedir         %{_libdir}/python%{python_version}