Add git revision

2 files changed, 14 insertions, 1 deletions

diff --git a/_includes/header.html b/_includes/header.html
index a39c338..7a339d5 100644
--- a/_includes/header.html
+++ b/_includes/header.html
@@ -1,5 +1,5 @@
 <header class="site-header" role="banner">
-
+  <!-- built from {% git_rev %} -->
   <div class="wrapper">
     <a class="site-title" rel="author" href="{{ "/" | relative_url }}">{{ site.title | escape }}</a>
 
diff --git a/_plugins/gitrev.rb b/_plugins/gitrev.rb
new file mode 100644
index 0000000..7f72bb9
--- /dev/null
+++ b/_plugins/gitrev.rb
@@ -0,0 +1,13 @@
+module Jekyll
+  class RenderGitVerTag < Liquid::Tag
+    def initialize(tag_name, text, tokens)
+      super
+    end
+
+    def render(context)
+      `git rev-parse HEAD`.strip
+    end
+  end
+end
+
+Liquid::Template.register_tag('git_rev', Jekyll::RenderGitVerTag)