diff --git a/bolognese.gemspec b/bolognese.gemspec
index 3cae8d3f..55c6c18e 100644
--- a/bolognese.gemspec
+++ b/bolognese.gemspec
@@ -23,7 +23,7 @@ Gem::Specification.new do |s|
   s.add_dependency 'builder', '~> 3.2', '>= 3.2.2'
   s.add_dependency 'activesupport', '>= 4.2.5'
   s.add_dependency 'bibtex-ruby', '>= 5.1.0'
-  s.add_dependency 'thor', '~> 1.0', '>= 1.0.1'
+  s.add_dependency 'thor', '>= 0.19'
   s.add_dependency 'colorize', '~> 0.8.1'
   s.add_dependency 'namae', '~> 1.0'
   s.add_dependency 'edtf', '~> 3.0', '>= 3.0.4'