diff --git a/lib/barbeque/executor/hako.rb b/lib/barbeque/executor/hako.rb
index 43c8835..056bee0 100644
--- a/lib/barbeque/executor/hako.rb
+++ b/lib/barbeque/executor/hako.rb
@@ -14,11 +14,20 @@ class HakoCommandError < StandardError
 
       # @param [String] hako_dir
       # @param [Hash] hako_env
-      # @param [String] yaml_dir
-      def initialize(hako_dir:, hako_env: {}, yaml_dir:, oneshot_notification_prefix:)
+      # @param [String] definition_dir
+      # @param [String] yaml_dir (deprecated: renamed to definition_dir)
+      def initialize(hako_dir:, hako_env: {}, yaml_dir: nil, definition_dir: nil, oneshot_notification_prefix:)
         @hako_dir = hako_dir
         @hako_env = hako_env
-        @yaml_dir = yaml_dir
+        @definition_dir =
+          if definition_dir
+            definition_dir
+          elsif yaml_dir
+            warn 'yaml_dir option is renamed to definition_dir. Please update config/barbeque.yml'
+            yaml_dir
+          else
+            raise ArgumentError.new('definition_dir is required')
+          end
         @hako_s3_client = HakoS3Client.new(oneshot_notification_prefix)
       end
 
@@ -104,10 +113,19 @@ def poll_retry(job_retry)
       private
 
       def build_hako_oneshot_command(docker_image, command, envs)
-        [
-          'bundle', 'exec', 'hako', 'oneshot', '--no-wait', '--tag', docker_image.tag,
-          *env_options(envs), File.join(@yaml_dir, "#{docker_image.repository}.yml"), '--', *command,
-        ]
+        jsonnet_path = File.join(@definition_dir, "#{docker_image.repository}.jsonnet")
+        yaml_path = File.join(@definition_dir, "#{docker_image.repository}.yml")
+
+        cmd = ['bundle', 'exec', 'hako', 'oneshot', '--no-wait', '--tag', docker_image.tag, *env_options(envs)]
+        if File.readable?(jsonnet_path)
+          cmd << jsonnet_path
+        elsif File.readable?(yaml_path)
+          cmd << yaml_path
+        else
+          raise HakoCommandError.new("No definition found matching '#{docker_image.repository}' in #{@definition_dir}")
+        end
+        cmd << '--'
+        cmd.concat(command)
       end
 
       def env_options(envs)
diff --git a/spec/barbeque/executor/hako_spec.rb b/spec/barbeque/executor/hako_spec.rb
index 358f037..2226885 100644
--- a/spec/barbeque/executor/hako_spec.rb
+++ b/spec/barbeque/executor/hako_spec.rb
@@ -9,7 +9,7 @@
     described_class.new(
       hako_dir: hako_directory,
       hako_env: hako_env,
-      yaml_dir: '/yamls',
+      definition_dir: '/yamls',
       oneshot_notification_prefix: 's3://barbeque/task_statuses?region=ap-northeast-1',
     )
   end
@@ -52,6 +52,8 @@
       let(:stderr) { '' }
 
       before do
+        allow(File).to receive(:readable?).with("/yamls/#{app_name}.jsonnet").and_return(false)
+        allow(File).to receive(:readable?).with("/yamls/#{app_name}.yml").and_return(true)
         expect(Open3).to receive(:capture3).with(
           hako_env,
           'bundle', 'exec', 'hako', 'oneshot', '--no-wait', '--tag', 'latest',
@@ -207,6 +209,8 @@
 
     describe '#start_retry' do
       before do
+        allow(File).to receive(:readable?).with("/yamls/#{app_name}.jsonnet").and_return(false)
+        allow(File).to receive(:readable?).with("/yamls/#{app_name}.yml").and_return(true)
         expect(Open3).to receive(:capture3).with(
           hako_env,
           'bundle', 'exec', 'hako', 'oneshot', '--no-wait', '--tag', 'latest',