diff --git a/Gemfile b/Gemfile
index 6ccc14fce09ec6daac174c9351603e0944cc0414..fc55e7ddc8c948d06cec7271c056097534ed27bb 100644
--- a/Gemfile
+++ b/Gemfile
@@ -2,3 +2,4 @@ source "http://rubygems.org"
 
 gem "nokogiri"
 gem "htmldiff"
+gem "zippy"
diff --git a/Gemfile.lock b/Gemfile.lock
new file mode 100644
index 0000000000000000000000000000000000000000..9ce805e75e3d815a0f2d634dd0f994d4dc8e6fcc
--- /dev/null
+++ b/Gemfile.lock
@@ -0,0 +1,16 @@
+GEM
+  remote: http://rubygems.org/
+  specs:
+    htmldiff (0.0.1)
+    nokogiri (1.5.9)
+    rubyzip (0.9.9)
+    zippy (0.2.1)
+      rubyzip (>= 0.9.1)
+
+PLATFORMS
+  ruby
+
+DEPENDENCIES
+  htmldiff
+  nokogiri
+  zippy
diff --git a/extract_amendments.rb b/extract_amendments.rb
new file mode 100755
index 0000000000000000000000000000000000000000..5b1fae457b0fd923458dfeb5eab68fd22ed85229
--- /dev/null
+++ b/extract_amendments.rb
@@ -0,0 +1,16 @@
+#!/usr/bin/env ruby
+
+require 'rubygems'
+require 'bundler/setup'
+require 'zippy'
+
+
+opendocument_path = ARGV.first
+raise "usage: #$0 <OpenDocument file>" unless opendocument_path
+
+xml = nil
+Zippy.open(opendocument_path) do |zip|
+  xml = zip['content.xml']
+end
+
+puts xml.size