diff --git a/Gemfile b/Gemfile
index c5f2cc3b..f96bc371 100644
--- a/Gemfile
+++ b/Gemfile
@@ -2,3 +2,4 @@ source 'https://rubygems.org'
 gemspec :name => "github-linguist"
 gemspec :name => "github-linguist-grammars"
 gem 'byebug' if RUBY_VERSION >= '2.0'
+gem 'licensor', :path => "../licensor"
diff --git a/script/licensor b/script/licensor
new file mode 100755
index 00000000..94309a3d
--- /dev/null
+++ b/script/licensor
@@ -0,0 +1,43 @@
+#!/usr/bin/env ruby
+
+# TODO: push these changes to licensor gem
+
+require "bundler/setup"
+require "licensor/cli"
+
+module Licensor
+  module Source
+    class Filesystem
+      attr_reader :type
+
+      def initialize(glob, type: "directory")
+        @glob = glob
+        @type = type
+      end
+
+      def enabled?
+        !Dir.glob(@glob).empty?
+      end
+
+      def dependencies
+        Dir.glob(@glob).map do |directory|
+          puts "caching #{directory}"
+          Licensor::Dependency.new(directory, {
+            "type" => type,
+            "name" => File.basename(directory)
+          })
+        end
+      end
+    end
+  end
+end
+
+source = Licensor::Source::Filesystem.new("vendor/grammars/*/", type: "grammar")
+config = Licensor::Configuration.new
+config.sources << source
+
+if ARGV[0] == "verify"
+  Licensor::Command::Verify.new(config).run
+else
+  Licensor::Command::Cache.new(config).run(force: true)
+end
diff --git a/vendor/licenses/config.yml b/vendor/licenses/config.yml
new file mode 100644
index 00000000..08a33f6b
--- /dev/null
+++ b/vendor/licenses/config.yml
@@ -0,0 +1,14 @@
+whitelist:
+  - apache-2.0
+  - bsd-2-clause
+  - bsd-3-clause
+  - mit
+
+# These dependencies are explicitly ignored
+ignored:
+  rubygem:
+    - bundler
+
+# These dependencies have been reviewed and approved.
+reviewed:
+  rubygem: