diff --git a/core/fg42/build/core.el b/core/fg42/build/core.el
index 8057556..ee9b95a 100644
--- a/core/fg42/build/core.el
+++ b/core/fg42/build/core.el
@@ -44,6 +44,11 @@
   "Where to find the docs. It sould be relative to the
 project root.")
 
+(defvar fg42/build-dev-base-url "http://localhost:3003"
+  "The base url to use with the docs for dev.")
+
+(defvar fg42/build-prod-base-url "https://fg42.org"
+  "The base url to use with the docs for production.")
 
 (defvar fg42/build-docs-actions nil
   "Set of actions to run before building the
diff --git a/core/fg42/build/docs.el b/core/fg42/build/docs.el
index 4a85d05..028ef92 100644
--- a/core/fg42/build/docs.el
+++ b/core/fg42/build/docs.el
@@ -272,7 +272,7 @@ Not pages."
 (defun fg42/build-docs (build-dir)
   "Build the documents and the website in the given BUILD-DIR."
 
-  (let ((base-url (if (prod-p) "https://fg42.org" "http://localhost:3003"))
+  (let ((base-url (if (prod-p) fg42/build-prod-base-url fg42/build-dev-base-url))
         (stage1-dir (expand-file-name "site" build-dir))
         (final-dir (expand-file-name "site-build" build-dir)))