diff --git a/siso b/siso
index 9b27844fda..6754b6eb03 100755
--- a/siso
+++ b/siso
@@ -5,4 +5,4 @@
 # found in the LICENSE file.
 
 base_dir=$(dirname "$0")
-PYTHONDONTWRITEBYTECODE=1 exec python3 "$base_dir/siso.py" "$@"
+PYTHONDONTWRITEBYTECODE=1 exec "$base_dir/python-bin/python3" "$base_dir/siso.py" "$@"
diff --git a/siso.bat b/siso.bat
index 28b03e49ef..16fa25f1ea 100644
--- a/siso.bat
+++ b/siso.bat
@@ -8,5 +8,7 @@ setlocal
 :: standalone, but allow other PATH manipulations to take priority.
 set PATH=%PATH%;%~dp0
 
+set scriptdir=%~dp0
+
 :: Defer control.
-python3 "%~dp0\siso.py" "%*"
+@call %scriptdir%python-bin\python3 "%~dp0\siso.py" "%*"