diff --git a/README.md b/README.md
index 6e8f33d..48d6a3d 100644
--- a/README.md
+++ b/README.md
@@ -18,6 +18,8 @@ Simply connect your browser to http://localhost:4000 and you're good to go. In d
 mode, the site has the [jekyll:livereload](https://github.com/RobertDeRose/jekyll-livereload) extension enabled, allowing you to see your changes immediately
 upon saving files in the source directory.
 
+If you change anything in `Gemfile` you need to run `docker-compose run jekyll bundle update` to update all your dependencies. 
+
 ## Deploying the site
 
 Simply pushing to `master` in our main repo at https://git.data.coop/data.coop/website/ will trigger a build-and-deploy of the website.