diff --git a/cheesy-gallery.gemspec b/cheesy-gallery.gemspec
index 7702f3c..2aec565 100644
--- a/cheesy-gallery.gemspec
+++ b/cheesy-gallery.gemspec
@@ -40,5 +40,5 @@ Gem::Specification.new do |spec|
   spec.add_development_dependency 'rubocop'
 
   spec.add_dependency 'jekyll', '~> 4.0'
-  spec.add_dependency 'rmagick', '~> 4.0'
+  spec.add_dependency 'rmagick', '>= 4', '< 6'
 end