diff --git a/build/py_admin.py b/build/py_admin.py
index 43509479e30fe5d6e2ef5f857871c2d3c68fe87e..bd8e6c97c73247ef35da9f7af7ec9c3416da24cc 100755
--- a/build/py_admin.py
+++ b/build/py_admin.py
@@ -1031,12 +1031,15 @@ F_compiler_opts_lines+'\n'+ \
 
         beg_cwd = os.getcwd()  # Record the current working directory
         os.chdir(absl_paths["makedir"])   # Enter the build "work" directory
-          # Use parallel compilation if available:
-        try:
-            subprocess.check_call([make_exe, "-f", absl_fpaths["makefile"],
-                                   "-j", '4'])
-        except:
+          # Use parallel compilation for non-debug build, if available:
+        if build_debug:
             subprocess.check_call([make_exe, "-f", absl_fpaths["makefile"]])
+        else:
+            try:
+                subprocess.check_call([make_exe, "-f", absl_fpaths["makefile"],
+                                       "-j", '4'])
+            except:
+                subprocess.check_call([make_exe, "-f", absl_fpaths["makefile"]])
 
           # Special actions for 'clavrxorb':
         if "clavrxorb" in os.path.basename(absl_fpaths["libexe"]):