diff --git a/doc/overlays.xml b/doc/overlays.xml
index c20045b217bd..cb54c33cf65f 100644
--- a/doc/overlays.xml
+++ b/doc/overlays.xml
@@ -29,12 +29,12 @@ first one present is considered, and all the rest are ignored:
In the directory pointed by the environment variable
-NIXPKGS_OVERLAYS.
+ NIXPKGS_OVERLAYS.
- In the directory ~/.nixpkgs/overlays/.
+ In the directory ~/.nixpkgs/overlays/.