diff --git a/variables.yml b/variables.yml
index 5c5c230..e4fc271 100644
--- a/variables.yml
+++ b/variables.yml
@@ -29,6 +29,9 @@ cargo_crate_list:
   - crate: watchexec-cli
     binary: watchexec
     version: 1.20.2
+  - crate: mdbook
+    binary: mdbook
+    version: 0.4.18
   - url: https://github.com/hakoerber/git-repo-manager
     binary: grm
     branch: develop