diff --git a/README.md b/README.md
index 073d528..6cc3162 100644
--- a/README.md
+++ b/README.md
@@ -32,7 +32,7 @@ You can choose the engine (e.g. to fall back to the Emacs regexp engine) with `v
 (define-key esc-map (kbd "C-r") 'vr/isearch-backward) ;; C-M-r
 (define-key esc-map (kbd "C-s") 'vr/isearch-forward) ;; C-M-s
 ```
-To customize, use `M-x customize-group [RET] visual-regexp`. You can specify which engine to use by modifying `vr/engine` (defaults to Python), and how the Python interpreter is invoked by modifying the `vr/command-python` variable. The default is `python /path/to/visual-regexp-steroids/regexp.py`.
+To customize, use `M-x customize-group [RET] visual-regexp`. You can specify which engine to use by modifying `vr/engine` (defaults to Python), and how the Python interpreter is invoked by modifying the `vr--python-interpreter` variable. The default is `python`.
 
 ## Examples
 
diff --git a/visual-regexp-steroids.el b/visual-regexp-steroids.el
index 83105a7..b806685 100644
--- a/visual-regexp-steroids.el
+++ b/visual-regexp-steroids.el
@@ -44,9 +44,13 @@
 (require 'visual-regexp)
 
 ;;; variables
+(defcustom vr/python-interpreter "python3"
+  "Name of current python interpreter on current machine."
+  :type 'string
+  :group 'visual-regexp)
 
 (defvar vr--command-python-default
-  (format "python %s" (expand-file-name "regexp.py" (file-name-directory load-file-name))))
+  (format "%s %s" vr/python-interpreter (expand-file-name "regexp.py" (file-name-directory load-file-name))))
 
 (defcustom vr/command-python vr--command-python-default
   "External command used for the Python engine."