diff --git a/Guardfile b/Guardfile
new file mode 100644
index 00000000..1508e4c9
--- /dev/null
+++ b/Guardfile
@@ -0,0 +1,6 @@
+guard :minitest do
+  # with Minitest::Unit
+  watch(%r{^test/(.*)\/?(.*)_test\.rb$})
+  watch(%r{^lib/zip/(.*/)?([^/]+)\.rb$}) { |m| "test/#{m[1]}#{m[2]}_test.rb" }
+  watch(%r{^test/test_helper\.rb$})      { 'test' }
+end
diff --git a/rubyzip.gemspec b/rubyzip.gemspec
index 3b575044..22344e84 100644
--- a/rubyzip.gemspec
+++ b/rubyzip.gemspec
@@ -20,4 +20,6 @@ spec = Gem::Specification.new do |s|
   s.add_development_dependency 'pry', '~> 0.10'
   s.add_development_dependency 'minitest', '~> 5.4'
   s.add_development_dependency 'coveralls', '~> 0.7'
+  s.add_development_dependency 'guard'
+  s.add_development_dependency 'guard-minitest'
 end