diff --git a/watch.sh b/watch.sh
index 01bb48ff..30956587 100755
--- a/watch.sh
+++ b/watch.sh
@@ -1,3 +1,8 @@
 #!/bin/bash
 
+if [ ! -d vendor/ ];
+  then
+    composer install
+fi
+
 ./vendor/bin/sculpin generate --server --watch --clean --no-interaction