diff --git a/README.md b/README.md
index 0f73c4b..0527f1e 100644
--- a/README.md
+++ b/README.md
@@ -2,6 +2,8 @@
 This is a small hack to send faxes via the sipgate REST API from the command line.
 
 ## Deployment
+Install [jq](https://stedolan.github.io/jq/download/).
+
 Add your login credentials to `login_credentials_muster.sh` and rename the file to `.env`
 
 If you use Letterheads Address database, uncomment the last line of that file and add `your/path/to/Letterhead`