diff --git a/requirements.txt b/requirements.txt
index 21c2a0c..1426ba3 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -1,6 +1,10 @@
 coverage
+matplotlib
+nbconvert
 networkx
 pillow
+pycodestyle
+pylint
 pyquickhelper>=1.9.3179
 sphinx_readable_theme
 wheel