diff --git a/requirements.txt b/requirements.txt
index 03be6c8..c8f2bcf 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -1,10 +1,10 @@
-toil[cwl]
-pip
-pytz
-typing
-bumpversion
-flake8
-tox
-twine
-pytest
-pytest-runner
+toil[cwl]==5.11.0
+pip==23.1.2
+pytz==2023.3
+typing==3.10.0.0
+bumpversion==0.6.0
+flake8==6.0.0
+tox==4.6.3
+twine==4.0.2
+pytest==7.4.0
+pytest-runner==6.0.0