diff --git a/crawler b/crawler
index eec3f11..8361475 100755
--- a/crawler
+++ b/crawler
@@ -1,4 +1,4 @@
-#!/usr/bin/env python3.6
+#!/usr/bin/env python3.7
 #
 # Copyright (C) 2016-2017 The University of Sheffield, UK
 #
diff --git a/crx-tool b/crx-tool
index 6138827..3945903 100755
--- a/crx-tool
+++ b/crx-tool
@@ -1,4 +1,4 @@
-#!/usr/bin/env python3.6
+#!/usr/bin/env python3.7
 #
 # Copyright (C) 2016 The University of Sheffield, UK
 #
diff --git a/singularity/ExtensionCrawler.def b/singularity/ExtensionCrawler.def
index cd47fcc..4307cb9 100644
--- a/singularity/ExtensionCrawler.def
+++ b/singularity/ExtensionCrawler.def
@@ -73,7 +73,7 @@ echo "LANG=en_US.UTF-8" > /etc/default/locale
 ###################################################################
 # Install the core dependencies (Python 3.6 or later)
 # from the Debian Testing repository
-apt-get	install -y --no-install-recommends python3-magic python3-minimal python3-pip python3-setuptools python3-mysqldb g++ git
+apt-get	install -y --no-install-recommends libpython3.7-dev python3-magic python3-minimal python3-pip python3-setuptools python3-mysqldb g++ git
 apt-get clean
 rm -rf /var/lib/apt/lists/* 
 ###################################################################