diff --git a/examples/overleaf/README.md b/examples/overleaf/README.md
index ccfb5b1..00dfecc 100644
--- a/examples/overleaf/README.md
+++ b/examples/overleaf/README.md
@@ -1,3 +1,13 @@
 # References
 
 - https://github.com/overleaf/overleaf
+- https://github.com/overleaf/overleaf/blob/main/docker-compose.yml
+
+# Notes
+
+- Download `mongodb-init-replica-set.js` next to this compose file before first startup:
+```bash
+  curl -o mongodb-init-replica-set.js https://raw.githubusercontent.com/overleaf/overleaf/main/bin/shared/mongodb-init-replica-set.js
+```
+- MongoDB runs with a replica set (`--replSet overleaf`), which is required by newer Overleaf versions
+- If migrating from an older setup (mongo 5.0, no replica set), initialize the replica set manually on existing data rather than relying on the init script