diff --git a/build/fbcode_builder/manifests/python b/build/fbcode_builder/manifests/python
index 83d62bb80..5adeae360 100644
--- a/build/fbcode_builder/manifests/python
+++ b/build/fbcode_builder/manifests/python
@@ -9,6 +9,9 @@ python3
 python3-devel
 
 # eden_scm needs dataclasses which arrive in 3.7, and the bionic python is 3.6
+[debs.all(distro=ubuntu,distro_vers="18.04")]
+python3.8-dev
+
 [debs.not(all(distro=ubuntu,distro_vers="18.04"))]
 python3-all-dev