diff --git a/setup.py b/setup.py
index 289498b6..1bb66760 100644
--- a/setup.py
+++ b/setup.py
@@ -27,8 +27,8 @@
 
 
 INSTALL_REQUIRES = [
-    'metomi-rose>=2.0b2',
-    'cylc-flow>=8.0b2',
+    'metomi-rose==2.0b2',
+    'cylc-flow==8.0b3.*',  # the .* permits dev versions
 ]
 EXTRAS_REQUIRE = {
 }