diff --git a/README.md b/README.md
index 99549f0..1cfbfc8 100644
--- a/README.md
+++ b/README.md
@@ -67,7 +67,7 @@ you can copy the example puzzles as a starting point:
 
 Then launch the development server:
 
-    $ python3 tools/devel-server.py
+    $ python3 devel/devel-server.py
 
 Point a web browser at http://localhost:8080/
 and start hacking on things in your `puzzles` directory.
diff --git a/docs/devel-server.md b/docs/devel-server.md
index bc05d3a..2ae34c8 100644
--- a/docs/devel-server.md
+++ b/docs/devel-server.md
@@ -28,6 +28,7 @@ If you can't use docker,
 try this:
 
 	apt install python3
+	pip3 install scapy pillow PyYAML
 	git clone https://github.com/dirtbags/moth/
 	cd moth
 	python3 devel/devel-server.py --puzzles example-puzzles