diff --git a/README.md b/README.md
index 75e1038..8ed0b52 100644
--- a/README.md
+++ b/README.md
@@ -82,6 +82,8 @@ src/LICENSE.chromium.
 Building from git
 -----------------
 
+You should have python2.7+ installed.
+
 Download project and prepare sources with
 
 		git clone http://github.com/rockdaboot/libpsl
diff --git a/configure.ac b/configure.ac
index e7a1273..a14f4ec 100644
--- a/configure.ac
+++ b/configure.ac
@@ -72,6 +72,9 @@ AS_IF([ test "$enable_man" != no ], [
   AC_MSG_RESULT([no])
 ])
 
+# src/make_dafsa.py needs python 2.7+
+AM_PATH_PYTHON([2.7])
+
 PKG_PROG_PKG_CONFIG
 
 # Define these substitions here to keep all version information in one place.