exe/circule in circule-0.1.0 vs exe/circule in circule-0.1.1

@@ -1,6 +1,7 @@
 #!/usr/bin/env ruby
+# frozen_string_literal: true
 
 require 'circule'
 require 'optparse'
 
 options = {}
@@ -81,20 +82,21 @@
     gui.save options[:save]
   end
 
   if options[:interactive]
     require 'pry'
+    require 'trace_eval' rescue nil
     Thread.new do gui.pry ensure `reset` end
   end
 
   gui.launch
 else
   case options[:file]
   when nil
   when '-'
     require 'digest'
-    options[:hex] = Digest::SHA256.hexdigest STDIN.read
+    options[:hex] = Digest::SHA256.hexdigest $stdin.read
   else
     require 'digest'
     options[:hex] = Digest::SHA256.hexdigest File.read(options[:file])
   end
 
@@ -111,10 +113,10 @@
       }.compact
   ).tap do |circule|
     case options[:save]
     when nil
     when '-'
-      circule.image.write STDOUT
+      circule.image.write $stdout
     else
       circule.image.save options[:save]
     end
   end
 end