diff --git a/requirements-dev.txt b/requirements-dev.txt
index b7af5fb..8866ae9 100644
--- a/requirements-dev.txt
+++ b/requirements-dev.txt
@@ -1,6 +1,7 @@
 # doc
 sphinx_rtd_theme
 Sphinx>=1.2.1
+markdown>=2.6
 # test suite
 pytest
 pytest-randomly>=1.1
diff --git a/requirements.txt b/requirements.txt
index 69dd60b..b1b4fad 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -2,8 +2,6 @@
 setuptools
 pyserial
 mlzlog >=0.2.0
-# for generating docu
-markdown>=2.6
 # daemonizing
 psutil
 python-daemon >=2.0