diff --git a/exe/pandoc2review b/exe/pandoc2review
index 99bc7a4..031583c 100755
--- a/exe/pandoc2review
+++ b/exe/pandoc2review
@@ -1,5 +1,12 @@
 #!/usr/bin/env ruby
 # -*- coding: utf-8 -*-
-# Copyright 2020 Kenshi Muto
+# Copyright 2020-2021 Kenshi Muto
+
+require 'pathname'
+bindir = Pathname.new(__FILE__).realpath.dirname
+$LOAD_PATH.unshift((bindir + '../lib').realpath)
+
 require 'pandoc2review'
-main
+
+p2r = Pandoc2ReVIEW.new
+p2r.main
diff --git a/lib/pandoc2review.rb b/lib/pandoc2review.rb
index 3a63aec..d362596 100644
--- a/lib/pandoc2review.rb
+++ b/lib/pandoc2review.rb
@@ -1,98 +1,99 @@
 # -*- coding: utf-8 -*-
-# Copyright 2020 Kenshi Muto
+# Copyright 2020-2021 Kenshi Muto
 require 'optparse'
 require 'unicode/eaw'
 require 'pathname'
 require 'open3'
 
-def main
-  luadir = Pathname.new(__FILE__).realpath.dirname
+class Pandoc2ReVIEW
+  def main
+    luadir = ((Pathname.new(__FILE__)).realpath.dirname + '../lua').realpath
+    parse_args
 
-  parse_args
+    ARGV.each do |file|
+      unless File.exist?(file)
+        puts "#{file} not exist. skip."
+        next
+      end
+      args = ['pandoc', '-t', File.join(luadir, 'review.lua'), '--lua-filter', File.join(luadir, 'filters.lua')]
 
-  ARGV.each do |file|
-    unless File.exist?(file)
-      puts "#{file} not exist. skip."
-      next
-    end
-    args = ['pandoc', '-t', File.join(luadir, 'review.lua'), '--lua-filter', File.join(luadir, 'filters.lua')]
+      if file =~ /\.md$/i
+        args += ['-f', 'markdown-auto_identifiers-smart+east_asian_line_breaks']
 
-    if file =~ /\.md$/i
-      args += ['-f', 'markdown-auto_identifiers-smart+east_asian_line_breaks']
+        if @disableeaw
+          args += ['-M', "softbreak:true"]
+        end
 
-      if @disableeaw
-        args += ['-M', "softbreak:true"]
+        if @hideraw
+          args += ['-M', "hideraw:true"]
+        end
       end
 
-      if @hideraw
-        args += ['-M', "hideraw:true"]
+      if @heading
+        args += ["--shift-heading-level-by=#{@heading}"]
       end
-    end
 
-    if @heading
-      args += ["--shift-heading-level-by=#{@heading}"]
-    end
-
-    args.push(file)
+      args.push(file)
 
-    stdout, stderr, status = Open3.capture3(*args)
-    unless status.success?
-      STDERR.puts stderr
-      exit 1
+      stdout, stderr, status = Open3.capture3(*args)
+      unless status.success?
+        STDERR.puts stderr
+        exit 1
+      end
+      print modify_result(stdout)
     end
-    print modify_result(stdout)
   end
-end
-
-def parse_args
-  @heading = nil
-  @disableeaw = nil
-  @hideraw = nil
-  opts = OptionParser.new
-  opts.banner = 'Usage: pandoc2review [option] file [file ...]'
-  opts.version = '1.0'
 
-  opts.on('--help', 'Prints this message and quit.') do
-    puts opts.help
-    exit 0
-  end
-  opts.on('--shiftheading num', 'Add <num> to heading level.') do |v|
-    @heading = v
-  end
-  opts.on('--disable-eaw', "Disable compositing a paragraph with Ruby's EAW library.") do
-    @disableeaw = true
-  end
-  opts.on('--hideraw', "Hide raw inline/block with no review format specified.") do
-    @hideraw = true
-  end
+  def parse_args
+    @heading = nil
+    @disableeaw = nil
+    @hideraw = nil
+    opts = OptionParser.new
+    opts.banner = 'Usage: pandoc2review [option] file [file ...]'
+    opts.version = '1.2'
+
+    opts.on('--help', 'Prints this message and quit.') do
+      puts opts.help
+      exit 0
+    end
+    opts.on('--shiftheading num', 'Add <num> to heading level.') do |v|
+      @heading = v
+    end
+    opts.on('--disable-eaw', "Disable compositing a paragraph with Ruby's EAW library.") do
+      @disableeaw = true
+    end
+    opts.on('--hideraw', "Hide raw inline/block with no review format specified.") do
+      @hideraw = true
+    end
 
-  opts.parse!(ARGV)
-  if ARGV.size != 1
-    puts opts.help
-    exit 0
+    opts.parse!(ARGV)
+    if ARGV.size != 1
+      puts opts.help
+      exit 0
+    end
   end
-end
 
-def modify_result(s)
-  s.gsub('<P2RBR/>') do
-    tail = $`[-1]
-    head = $'[0]
-    return '' if tail.nil? || head.nil?
+  def modify_result(s)
+    s.gsub('<P2RBR/>') do
+      tail = $`[-1]
+      head = $'[0]
+      return '' if tail.nil? || head.nil?
+
+      space = ' '
+      if %i[F W H].include?(Unicode::Eaw.property(tail)) &&
+         %i[F W H].include?(Unicode::Eaw.property(head)) &&
+         tail !~ /\p{Hangul}/ && head !~ /\p{Hangul}/
+        space = ''
+      end
 
-    space = ' '
-    if %i[F W H].include?(Unicode::Eaw.property(tail)) &&
-       %i[F W H].include?(Unicode::Eaw.property(head)) &&
-       tail !~ /\p{Hangul}/ && head !~ /\p{Hangul}/
-      space = ''
-    end
+      if (%i[F W H].include?(Unicode::Eaw.property(tail)) &&
+          tail !~ /\p{Hangul}/) ||
+         (%i[F W H].include?(Unicode::Eaw.property(head)) &&
+          head !~ /\p{Hangul}/)
+        space = ''
+      end
 
-    if (%i[F W H].include?(Unicode::Eaw.property(tail)) &&
-     tail !~ /\p{Hangul}/) ||
-      (%i[F W H].include?(Unicode::Eaw.property(head)) &&
-       head !~ /\p{Hangul}/)
-      space = ''
+      space
     end
-
-    space
   end
 end
diff --git a/lib/filters.lua b/lua/filters.lua
similarity index 100%
rename from lib/filters.lua
rename to lua/filters.lua
diff --git a/lib/review.lua b/lua/review.lua
similarity index 100%
rename from lib/review.lua
rename to lua/review.lua
diff --git a/pandoc2review.gemspec b/pandoc2review.gemspec
index e3b9ba8..e125940 100644
--- a/pandoc2review.gemspec
+++ b/pandoc2review.gemspec
@@ -3,7 +3,7 @@ Gem::Specification.new do |spec|
   # spec.version       = Pandoc2review::VERSION
   spec.version       = "1.1.0"
   spec.authors       = ["kmuto"]
-  spec.email         = ["kmuto@debian.org"]
+  spec.email         = ["kmuto@kmuto.jp"]
 
   spec.summary       = %q{Re:VIEW Filter/Writer for Pandoc.}
   spec.description   = %q{Re:VIEW Filter/Writer for Pandoc.}
@@ -21,7 +21,7 @@ Gem::Specification.new do |spec|
   end
   spec.bindir        = "exe"
   spec.executables   = spec.files.grep(%r{^exe/}) { |f| File.basename(f) }
-  spec.require_paths = ["lib"]
+  spec.require_paths = ["lib", "lua"]
 
   spec.add_dependency('unicode-eaw')
   spec.add_development_dependency('simplecov')
diff --git a/test/test_helper.rb b/test/test_helper.rb
index 67299a5..5dbd598 100644
--- a/test/test_helper.rb
+++ b/test/test_helper.rb
@@ -3,15 +3,16 @@
 require 'open3'
 
 def pandoc(src, opts: nil, err: nil)
-  args = 'pandoc -t lib/review.lua --lua-filter=lib/filters.lua -f markdown-auto_identifiers-smart+east_asian_line_breaks'
+  args = 'pandoc -t lua/review.lua --lua-filter=lua/filters.lua -f markdown-auto_identifiers-smart+east_asian_line_breaks'
+  p2r = Pandoc2ReVIEW.new
   if opts
     args += ' ' + opts
   end
   if err
     stdout, stderr, status = Open3.capture3(args, stdin_data: src)
-    return modify_result(stdout), stderr
+    [p2r.modify_result(stdout), stderr]
   else
     stdout, status = Open3.capture2(args, stdin_data: src)
-    modify_result(stdout)
+    p2r.modify_result(stdout)
   end
 end