diff --git a/.buckconfig.d/external_cells/facebook/folly/external_cell.buckconfig b/.buckconfig.d/external_cells/facebook/folly/external_cell.buckconfig
new file mode 100644
index 000000000..41a541b7b
--- /dev/null
+++ b/.buckconfig.d/external_cells/facebook/folly/external_cell.buckconfig
@@ -0,0 +1,9 @@
+[cells]
+gh_facebook_folly = gh_facebook_folly
+
+[external_cells]
+gh_facebook_folly = git
+
+[external_cell_gh_facebook_folly]
+git_origin = https://github.com/facebook/folly.git
+commit_hash = 264b8b73a0ea6724782d5e7086a4da021995c2b7
diff --git a/.buckconfig.d/external_cells/facebookincubator/fizz/external_cell.buckconfig b/.buckconfig.d/external_cells/facebookincubator/fizz/external_cell.buckconfig
new file mode 100644
index 000000000..a43b19d75
--- /dev/null
+++ b/.buckconfig.d/external_cells/facebookincubator/fizz/external_cell.buckconfig
@@ -0,0 +1,9 @@
+[cells]
+gh_facebookincubator_fizz = gh_facebookincubator_fizz
+
+[external_cells]
+gh_facebookincubator_fizz = git
+
+[external_cell_gh_facebookincubator_fizz]
+git_origin = https://github.com/facebookincubator/fizz.git
+commit_hash = b9f6a81e756493729eabce1a86576d1ad7bb4c53