diff --git a/requirements-dev.txt b/requirements-dev.txt
index 2f77c43..0412c5e 100644
--- a/requirements-dev.txt
+++ b/requirements-dev.txt
@@ -1,6 +1,6 @@
-ipdb
-coverage
-pytest
-pytest-cov
-pep8
-pyflakes
+ipdb==0.10.1
+coverage==4.2
+pytest==3.0.2
+pytest-cov==2.3.1
+pep8==1.7.0
+pyflakes==1.3.0