diff --git a/.circleci/config.yml b/.circleci/config.yml
new file mode 100644
index 0000000..7fef5ff
--- /dev/null
+++ b/.circleci/config.yml
@@ -0,0 +1,28 @@
+version: 2.1
+
+orbs:
+  ruby-orbs: sue445/ruby-orbs@volatile
+
+jobs:
+  test:
+    docker:
+      - image: cimg/ruby:3.0
+        environment:
+          AWS_REGION: ap-northeast-1
+          AWS_ACCESS_KEY_ID: dummy
+          AWS_SECRET_ACCESS_KEY: dummy
+      - image: amazon/dynamodb-local
+        environment:
+          AWS_REGION: ap-northeast-1
+    steps:
+      - checkout
+      - ruby-orbs/bundle-install:
+          gemspec_name: fluent-plugin-dynamodb-add
+          with_gemfile_lock: false
+
+      - run: bundle exec rake test
+
+workflows:
+  test:
+    jobs:
+      - test
diff --git a/Gemfile b/Gemfile
index fa75df1..a4fd5e9 100644
--- a/Gemfile
+++ b/Gemfile
@@ -1,3 +1,5 @@
 source 'https://rubygems.org'
 
 gemspec
+
+gem 'rexml'
diff --git a/Rakefile b/Rakefile
index f5e4c3f..4d9509e 100644
--- a/Rakefile
+++ b/Rakefile
@@ -1,9 +1,11 @@
 require "bundler/gem_tasks"
 require 'rake/testtask'
 
+Rake::Task[:release].clear
+
 Rake::TestTask.new(:test) do |test|
   test.libs << 'lib' << 'test'
-  test.test_files = FileList['test/test_*.rb']
+  test.pattern = 'test/**/test_*.rb'
   test.verbose = true
 end
 
diff --git a/fluent-plugin-dynamodb-add.gemspec b/fluent-plugin-dynamodb-add.gemspec
index 88d2c93..4bffc9f 100644
--- a/fluent-plugin-dynamodb-add.gemspec
+++ b/fluent-plugin-dynamodb-add.gemspec
@@ -17,8 +17,10 @@ Gem::Specification.new do |spec|
   spec.test_files    = spec.files.grep(%r{^(test|spec|features)/})
   spec.require_paths = ["lib"]
 
-  spec.add_development_dependency "bundler", "~> 1.7"
-  spec.add_development_dependency "rake", "~> 10.0"
-  spec.add_dependency "fluentd", "~> 0.10.0"
-  spec.add_dependency "aws-sdk", ">= 1.56.0", "< 2.0.0"
+  spec.add_development_dependency "bundler"
+  spec.add_development_dependency "rake"
+  spec.add_development_dependency "test-unit"
+
+  spec.add_dependency "fluentd", ">= 1", "< 2"
+  spec.add_dependency "aws-sdk-dynamodb"
 end
diff --git a/lib/fluent/plugin/out_dynamodb_add.rb b/lib/fluent/plugin/out_dynamodb_add.rb
index 22dfe27..eb0bbbd 100644
--- a/lib/fluent/plugin/out_dynamodb_add.rb
+++ b/lib/fluent/plugin/out_dynamodb_add.rb
@@ -1,87 +1,100 @@
-module Fluent
-  class DynamodbAdd < Fluent::Output
-    Fluent::Plugin.register_output('dynamodb_add', self)
+require 'aws-sdk-dynamodb'
+require 'fluent/plugin/output'
 
-    unless method_defined?(:log)
-      define_method(:log) { $log }
-    end
+class Fluent::Plugin::DynamodbAdd < Fluent::Plugin::Output
+  Fluent::Plugin.register_output('dynamodb_add', self)
 
-    config_param :count_key, :string
-    config_param :dynamo_count_key, :string
-    config_param :table_name, :string
-    config_param :use_iam_role, :bool, :default => false
-    config_param :aws_key_id, :string, :default => nil
-    config_param :aws_sec_key, :string, :default => nil
-    config_param :endpoint, :string, :default => nil
-    config_param :hash_key, :string, :default => nil
-    config_param :hash_key_delimiter, :string, :default => ":"
-    config_param :add_hash_key_prefix, :string, :default => nil
-    config_param :range_key, :string, :default => nil
-    config_param :set_timestamp, :string, :default => nil
-
-    def initialize
-      super
-      require 'aws-sdk-v1'
-    end
+  helpers :event_emitter
+  helpers :compat_parameters
+
+  config_param :count_key, :string
+  config_param :dynamo_count_key, :string
+  config_param :table_name, :string
+  config_param :use_iam_role, :bool, :default => false
+  config_param :aws_key_id, :string, :default => nil
+  config_param :aws_sec_key, :string, :default => nil
+  config_param :region, :string, :default => nil
+  config_param :endpoint, :string, :default => nil
+  config_param :hash_key, :string, :default => nil
+  config_param :hash_key_delimiter, :string, :default => ":"
+  config_param :add_hash_key_prefix, :string, :default => nil
+  config_param :range_key, :string, :default => nil
+  config_param :set_timestamp, :string, :default => nil
+
+  def initialize
+    super
+  end
 
-    def configure(conf)
-      super
+  def configure(conf)
+    compat_parameters_convert(conf)
 
-      unless use_iam_role
-        [:aws_key_id, :aws_sec_key].each do |name|
-          unless self.instance_variable_get("@#{name}")
-            raise ConfigError, "'#{name}' is required"
-          end
+    super
+
+    unless use_iam_role
+    [:aws_key_id, :aws_sec_key].each do |name|
+        unless self.instance_variable_get("@#{name}")
+          raise ConfigError, "'#{name}' is required"
         end
       end
-      @hash_key = hash_key.split(/\s*,\s*/)
     end
+    @hash_key = hash_key.split(/\s*,\s*/)
+  end
 
-    def start
-      super
-      if use_iam_role
-        AWS.config(:credential_provider => AWS::Core::CredentialProviders::EC2Provider.new)
-      else
-        AWS.config(:access_key_id => @aws_key_id, :secret_access_key => @aws_sec_key)
-      end
+  def start
+    super
 
-      AWS.config(:dynamo_db_endpoint => @endpoint) if @endpoint
+    options = {}
 
-      @dynamo_db = AWS::DynamoDB.new
-      @table = @dynamo_db.tables[table_name]
-      @table.load_schema
+    unless use_iam_role
+      options[:access_key_id] = @aws_key_id
+      options[:secret_access_key] = @aws_sec_key
     end
 
-    def emit(tag, es, chain)
-      chain.next
-      es.each do |time, record|
-        hash_key = create_key(record)
-        next unless hash_key || record[@count_key]
-
-        if @range_key
-          next unless record[@range_key]
-          item = @table.items[hash_key, record[@range_key]]
-        else
-          item = @table.items[hash_key]
-        end
-        item.attributes.update {|u|
-          u.add @dynamo_count_key => record[@count_key]
-          if @set_timestamp
-            u.set @set_timestamp => Time.now.to_i
-          end
-        }
+    options[:region] = region
+    options[:endpoint] = endpoint
+
+    client = Aws::DynamoDB::Client.new(options)
+
+    resource = Aws::DynamoDB::Resource.new(client: client)
+    @table = resource.table(table_name)
+
+    @dynamo_hash_key = @table.key_schema.find{|e| e.key_type == "HASH" }.attribute_name
+    @dynamo_range_key = @table.key_schema.find{|e| e.key_type == "RANGE" }&.attribute_name
+  end
+
+  def process(tag, es)
+    es.each do |time, record|
+      hash_key = create_key(record)
+      next unless hash_key || record[@count_key]
+
+      key = { @dynamo_hash_key => hash_key }
+
+      if @range_key
+        next unless record[@range_key]
+        key[@dynamo_range_key] = record[@range_key]
       end
+
+      @table.update_item({
+        key: key,
+        attribute_updates: {
+          @dynamo_count_key => {
+            value: record[@count_key],
+            action: "ADD"
+          },
+        },
+      })
     end
+  end
 
-    private
-    def create_key(record)
-      key_array = []
-      key_array << @add_hash_key_prefix if @add_hash_key_prefix
-      @hash_key.each do |h|
-        return nil unless record[h]
-        key_array << record[h]
-      end
-      key_array.join(@hash_key_delimiter)
+  private
+
+  def create_key(record)
+    key_array = []
+    key_array << @add_hash_key_prefix if @add_hash_key_prefix
+    @hash_key.each do |h|
+      return nil unless record[h]
+      key_array << record[h]
     end
+    key_array.join(@hash_key_delimiter)
   end
 end
diff --git a/test/helper.rb b/test/helper.rb
new file mode 100644
index 0000000..f9e989a
--- /dev/null
+++ b/test/helper.rb
@@ -0,0 +1,8 @@
+$LOAD_PATH.unshift(File.expand_path("../../", __FILE__))
+require "test-unit"
+require "fluent/test"
+require "fluent/test/driver/output"
+require "fluent/test/helpers"
+
+Test::Unit::TestCase.include(Fluent::Test::Helpers)
+Test::Unit::TestCase.extend(Fluent::Test::Helpers)
diff --git a/test/plugin/test_out_dynamodb_add.rb b/test/plugin/test_out_dynamodb_add.rb
new file mode 100644
index 0000000..0e4901c
--- /dev/null
+++ b/test/plugin/test_out_dynamodb_add.rb
@@ -0,0 +1,269 @@
+require 'helper'
+
+require 'fluent/plugin/out_dynamodb_add'
+require 'aws-sdk-dynamodb'
+
+class DynamodbAddTest < Test::Unit::TestCase
+  include Fluent::Test::Helpers
+
+  def setup
+    Fluent::Test.setup
+  end
+
+  CONFIG = %[
+    count_key test_count_key
+    dynamo_count_key test_dynamo_count_key
+    table_name test_table_name
+    use_iam_role false
+    aws_key_id test_aws_key_id
+    aws_sec_key test_aws_sec_key
+    endpoint https://test_endpoint
+    hash_key test_hash_key1,test_hash_key2
+    hash_key_delimiter :
+    add_hash_key_prefix 3
+    range_key test_range_key
+    ]
+
+  def create_driver(conf = CONFIG)
+    Fluent::Test::Driver::Output.new(Fluent::Plugin::DynamodbAdd).configure(conf)
+  end
+
+  sub_test_case 'confguration' do
+    def test_configure_not_use_iam_role
+      d = create_driver
+      assert_equal 'test_count_key', d.instance.count_key
+      assert_equal 'test_dynamo_count_key', d.instance.dynamo_count_key
+      assert_equal 'test_table_name', d.instance.table_name
+      assert_equal false, d.instance.use_iam_role
+      assert_equal 'test_aws_key_id', d.instance.aws_key_id
+      assert_equal 'test_aws_sec_key', d.instance.aws_sec_key
+      assert_equal 'https://test_endpoint', d.instance.endpoint
+      assert_equal ['test_hash_key1','test_hash_key2'], d.instance.hash_key
+      assert_equal ':', d.instance.hash_key_delimiter
+      assert_equal '3', d.instance.add_hash_key_prefix
+      assert_equal 'test_range_key', d.instance.range_key
+    end
+
+    def test_configure_use_iam_role
+      conf = CONFIG.clone
+      conf.gsub!(/use_iam_role\sfalse/, "use_iam_role true")
+      conf.gsub!(/aws_key_id\stest_aws_key_id/, "")
+      conf.gsub!(/aws_sec_key\stest_aws_sec_key/, "")
+
+      d = create_driver(conf)
+      assert_equal 'test_count_key', d.instance.count_key
+      assert_equal 'test_dynamo_count_key', d.instance.dynamo_count_key
+      assert_equal 'test_table_name', d.instance.table_name
+      assert_equal true, d.instance.use_iam_role
+      assert_equal nil, d.instance.aws_key_id
+      assert_equal nil, d.instance.aws_sec_key
+      assert_equal 'https://test_endpoint', d.instance.endpoint
+      assert_equal ['test_hash_key1','test_hash_key2'], d.instance.hash_key
+      assert_equal ':', d.instance.hash_key_delimiter
+      assert_equal '3', d.instance.add_hash_key_prefix
+      assert_equal 'test_range_key', d.instance.range_key
+    end
+
+    def test_configure_not_use_iam_role_and_not_set_range_key
+      conf = CONFIG.clone
+      conf.gsub!(/range_key\stest_range_key/, "")
+
+      d = create_driver(conf)
+      assert_equal 'test_count_key', d.instance.count_key
+      assert_equal 'test_dynamo_count_key', d.instance.dynamo_count_key
+      assert_equal 'test_table_name', d.instance.table_name
+      assert_equal false, d.instance.use_iam_role
+      assert_equal 'test_aws_key_id', d.instance.aws_key_id
+      assert_equal 'test_aws_sec_key', d.instance.aws_sec_key
+      assert_equal 'https://test_endpoint', d.instance.endpoint
+      assert_equal ['test_hash_key1','test_hash_key2'], d.instance.hash_key
+      assert_equal ':', d.instance.hash_key_delimiter
+      assert_equal '3', d.instance.add_hash_key_prefix
+      assert_equal nil, d.instance.range_key
+    end
+
+    def test_configure_set_timestamp
+      conf = CONFIG.clone
+      conf << " set_timestamp last_updated_at"
+
+      d = create_driver(conf)
+      assert_equal 'test_count_key', d.instance.count_key
+      assert_equal 'test_dynamo_count_key', d.instance.dynamo_count_key
+      assert_equal 'test_table_name', d.instance.table_name
+      assert_equal false, d.instance.use_iam_role
+      assert_equal 'test_aws_key_id', d.instance.aws_key_id
+      assert_equal 'test_aws_sec_key', d.instance.aws_sec_key
+      assert_equal 'https://test_endpoint', d.instance.endpoint
+      assert_equal ['test_hash_key1','test_hash_key2'], d.instance.hash_key
+      assert_equal ':', d.instance.hash_key_delimiter
+      assert_equal '3', d.instance.add_hash_key_prefix
+      assert_equal 'test_range_key', d.instance.range_key
+      assert_equal 'last_updated_at', d.instance.set_timestamp
+    end
+  end
+
+
+  def test_count_with_range_key_table
+    table_name = 'sample_table'
+
+    create_table(dynamodb_client, table_with_range_key(table_name))
+
+    d = create_driver(
+      <<~EOS
+      count_key count
+      hash_key project_id
+
+      table_name #{table_name}
+      range_key time
+      dynamo_count_key count
+
+      endpoint http://localhost:8000
+      region ap-northeast-1
+      aws_key_id dummy
+      aws_sec_key dummy
+      EOS
+    )
+
+    resource = Aws::DynamoDB::Resource.new(client: dynamodb_client)
+    @table = resource.table(table_name)
+
+    time = 1000
+
+    d.run(default_tag: 'test') do
+      d.feed(event_time('2022-09-01 10:00:00 UTC'), {'count' => 1, 'project_id' => 1, 'time' => time})
+      d.feed(event_time('2022-09-01 10:00:00 UTC'), {'count' => 2, 'project_id' => 1, 'time' => time})
+      d.feed(event_time('2022-09-01 10:00:00 UTC'), {'count' => 4, 'project_id' => 1, 'time' => 2000})
+    end
+
+    item = @table.get_item(key: { 'Id': '1', 'ViewTimestamp': time.to_i}).item
+
+    assert_equal 3, item['count']
+
+    d.run(default_tag: 'test') do
+      d.feed(event_time('2022-09-01 10:00:00 UTC'), {'count' =>  8, 'project_id' => 1, 'time' => time})
+      d.feed(event_time('2022-09-01 10:00:00 UTC'), {'count' => 16, 'project_id' => 1, 'time' => time})
+      d.feed(event_time('2022-09-01 10:00:00 UTC'), {'count' => 32, 'project_id' => 1, 'time' => 2000})
+    end
+
+    item = @table.get_item(key: { 'Id': '1', 'ViewTimestamp': time.to_i}).item
+
+    assert_equal 27, item['count']
+
+    delete_table(dynamodb_client, table_name)
+  end
+
+  def test_count_with_no_range_key_table
+    table_name = 'sample_table'
+
+    create_table(dynamodb_client, table_without_range_key(table_name))
+
+    d = create_driver(
+      <<~EOS
+      count_key count
+      hash_key project_id
+
+      table_name #{table_name}
+      dynamo_count_key count
+
+      endpoint http://localhost:8000
+      region ap-northeast-1
+      aws_key_id dummy
+      aws_sec_key dummy
+      EOS
+    )
+
+    resource = Aws::DynamoDB::Resource.new(client: dynamodb_client)
+    @table = resource.table(table_name)
+
+    d.run(default_tag: 'test') do
+      d.feed(event_time('2022-09-01 10:00:00 UTC'), {'count' => 1, 'project_id' => 1})
+      d.feed(event_time('2022-09-01 10:00:00 UTC'), {'count' => 2, 'project_id' => 1})
+    end
+
+    item = @table.get_item(key: { 'Id': '1'}).item
+
+    assert_equal 3, item['count']
+
+    d.run(default_tag: 'test') do
+      d.feed(event_time('2022-09-01 10:00:00 UTC'), {'count' => 4, 'project_id' => 1})
+      d.feed(event_time('2022-09-01 10:00:00 UTC'), {'count' => 8, 'project_id' => 1})
+    end
+    
+    item = @table.get_item(key: { 'Id': '1'}).item
+
+    assert_equal 15, item['count']
+
+    delete_table(dynamodb_client, table_name)
+  end
+
+  private
+
+  def create_table(dynamodb_client, table_definition)
+    response = dynamodb_client.create_table(table_definition)
+    response.table_description.table_status
+  rescue StandardError => e
+    binding.irb
+  end
+
+  def delete_table(dynamodb_client, table_name)
+    dynamodb_client.delete_table(
+      table_name: table_name
+    )
+  end
+
+  def table_without_range_key(table_name)
+    table_definition = {
+      table_name: table_name, 
+      key_schema: [
+        {
+          attribute_name: 'Id',
+          key_type: 'HASH'  # Partition key.
+        },
+      ],
+      attribute_definitions: [
+        {
+          attribute_name: 'Id',
+          attribute_type: 'S'
+        },
+      ],
+      billing_mode: "PAY_PER_REQUEST",
+    }
+  end
+
+  def table_with_range_key(table_name)
+    table_definition = {
+      table_name: table_name,
+      key_schema: [
+        {
+          attribute_name: 'Id',
+          key_type: 'HASH'  # Partition key.
+        },
+        {
+          attribute_name: 'ViewTimestamp',
+          key_type: 'RANGE' # Sort key.
+        }
+      ],
+      attribute_definitions: [
+        {
+          attribute_name: 'Id',
+          attribute_type: 'S'
+        },
+        {
+          attribute_name: 'ViewTimestamp',
+          attribute_type: 'N'
+        }
+      ],
+      billing_mode: "PAY_PER_REQUEST",
+    }
+  end
+
+
+  def dynamodb_client
+    @client ||= Aws::DynamoDB::Client.new({
+      access_key_id: 'dummy',
+      secret_access_key: 'dummy',
+      endpoint: 'http://localhost:8000',
+      region: 'ap-northeast-1'
+    })
+  end
+end
diff --git a/test/test_out_dynamodb_add.rb b/test/test_out_dynamodb_add.rb
deleted file mode 100644
index 32eaaa2..0000000
--- a/test/test_out_dynamodb_add.rb
+++ /dev/null
@@ -1,103 +0,0 @@
-require 'fluent/test'
-require 'fluent/plugin/out_dynamodb_add'
-
-class DynamodbAddTest < Test::Unit::TestCase
-  def setup
-    Fluent::Test.setup
-  end
-
-  CONFIG = %[
-    count_key test_count_key
-    dynamo_count_key test_dynamo_count_key
-    table_name test_table_name
-    use_iam_role false
-    aws_key_id test_aws_key_id
-    aws_sec_key test_aws_sec_key
-    endpoint https://test_endpoint
-    hash_key test_hash_key1,test_hash_key2
-    hash_key_delimiter :
-    add_hash_key_prefix 3
-    range_key test_range_key
-  ]
-
-  def create_driver(conf = CONFIG)
-    Fluent::Test::OutputTestDriver.new(Fluent::DynamodbAdd) do
-      def write(chunk)
-        chunk.read
-      end
-    end.configure(conf)
-  end
-
-  def test_configure_not_use_iam_role
-    d = create_driver
-    assert_equal 'test_count_key', d.instance.count_key
-    assert_equal 'test_dynamo_count_key', d.instance.dynamo_count_key
-    assert_equal 'test_table_name', d.instance.table_name
-    assert_equal false, d.instance.use_iam_role
-    assert_equal 'test_aws_key_id', d.instance.aws_key_id
-    assert_equal 'test_aws_sec_key', d.instance.aws_sec_key
-    assert_equal 'https://test_endpoint', d.instance.endpoint
-    assert_equal ['test_hash_key1','test_hash_key2'], d.instance.hash_key
-    assert_equal ':', d.instance.hash_key_delimiter
-    assert_equal '3', d.instance.add_hash_key_prefix
-    assert_equal 'test_range_key', d.instance.range_key
-  end
-
-  def test_configure_use_iam_role
-    conf = CONFIG.clone
-    conf.gsub!(/use_iam_role\sfalse/, "use_iam_role true")
-    conf.gsub!(/aws_key_id\stest_aws_key_id/, "")
-    conf.gsub!(/aws_sec_key\stest_aws_sec_key/, "")
-
-    d = create_driver(conf)
-    assert_equal 'test_count_key', d.instance.count_key
-    assert_equal 'test_dynamo_count_key', d.instance.dynamo_count_key
-    assert_equal 'test_table_name', d.instance.table_name
-    assert_equal true, d.instance.use_iam_role
-    assert_equal nil, d.instance.aws_key_id
-    assert_equal nil, d.instance.aws_sec_key
-    assert_equal 'https://test_endpoint', d.instance.endpoint
-    assert_equal ['test_hash_key1','test_hash_key2'], d.instance.hash_key
-    assert_equal ':', d.instance.hash_key_delimiter
-    assert_equal '3', d.instance.add_hash_key_prefix
-    assert_equal 'test_range_key', d.instance.range_key
-  end
-
-  def test_configure_not_use_iam_role_and_not_set_range_key
-    conf = CONFIG.clone
-    conf.gsub!(/range_key\stest_range_key/, "")
-
-    d = create_driver(conf)
-    assert_equal 'test_count_key', d.instance.count_key
-    assert_equal 'test_dynamo_count_key', d.instance.dynamo_count_key
-    assert_equal 'test_table_name', d.instance.table_name
-    assert_equal false, d.instance.use_iam_role
-    assert_equal 'test_aws_key_id', d.instance.aws_key_id
-    assert_equal 'test_aws_sec_key', d.instance.aws_sec_key
-    assert_equal 'https://test_endpoint', d.instance.endpoint
-    assert_equal ['test_hash_key1','test_hash_key2'], d.instance.hash_key
-    assert_equal ':', d.instance.hash_key_delimiter
-    assert_equal '3', d.instance.add_hash_key_prefix
-    assert_equal nil, d.instance.range_key
-  end
-
-  def test_configure_set_timestamp
-    conf = CONFIG.clone
-    conf << " set_timestamp last_updated_at"
-
-    d = create_driver(conf)
-    assert_equal 'test_count_key', d.instance.count_key
-    assert_equal 'test_dynamo_count_key', d.instance.dynamo_count_key
-    assert_equal 'test_table_name', d.instance.table_name
-    assert_equal false, d.instance.use_iam_role
-    assert_equal 'test_aws_key_id', d.instance.aws_key_id
-    assert_equal 'test_aws_sec_key', d.instance.aws_sec_key
-    assert_equal 'https://test_endpoint', d.instance.endpoint
-    assert_equal ['test_hash_key1','test_hash_key2'], d.instance.hash_key
-    assert_equal ':', d.instance.hash_key_delimiter
-    assert_equal '3', d.instance.add_hash_key_prefix
-    assert_equal 'test_range_key', d.instance.range_key
-    assert_equal 'last_updated_at', d.instance.set_timestamp
-  end
-end
-