diff --git a/.hgignore b/.hgignore
--- a/.hgignore
+++ b/.hgignore
@@ -22,7 +22,7 @@ syntax: regexp
 ^\.project$
 ^\.pydevproject$
 ^\.coverage$
-^kallithea/public/css/style\.css$
+^kallithea/public/css/style\.css(\.map)?$
 ^theme\.less$
 ^kallithea\.db$
 ^test\.db$
diff --git a/package.json b/package.json
--- a/package.json
+++ b/package.json
@@ -9,6 +9,6 @@
     "less-plugin-clean-css": "~1.5"
   },
   "scripts": {
-    "less": "lessc --relative-urls kallithea/public/less/main.less kallithea/public/css/style.css"
+    "less": "lessc --relative-urls --source-map --source-map-less-inline kallithea/public/less/main.less kallithea/public/css/style.css"
   }
 }