diff --git a/.bazelignore b/.bazelignore
new file mode 100644
index 00000000000..eda018aeb29
--- /dev/null
+++ b/.bazelignore
@@ -0,0 +1,3 @@
+# Without this, Bazel will consider BUILD.bazel files in
+# .git/sl/origbackups (which can be populated by Sapling SCM).
+.git