diff --git a/CONTRIBUTING.md b/CONTRIBUTING.md
index 7ce9c273247..92eb719f4cb 100644
--- a/CONTRIBUTING.md
+++ b/CONTRIBUTING.md
@@ -53,6 +53,7 @@ repository:
 ```bash
 git clone git@github.com:firebase/firebase-tools.git
 cd firebase-tools
+npm install # must be run the first time you clone
 npm link  # installs dependencies, runs a build, links it into the environment
 ```