AWS supports the following Ruby runtimes:

<!--StartFragment-->
Name | Identifier | SDK for Ruby | Operating system
-- | -- | -- | --
Ruby 2.7 | ruby2.7 | 3.0.1 | Amazon Linux 2
Ruby 2.5 | ruby2.5 | 3.0.1 | Amazon Linux

<!--EndFragment-->

Currently, `localstack/lambda` only contains the `ruby2.5` tag. Will the 2.7 runtime be supported in the (near) future?
self.check_lambda_logs(
            TEST_LAMBDA_NAME_CUSTOM_RUNTIME, expected_lines=expected)
        
        testutil.delete_lambda_function(TEST_LAMBDA_NAME_CUSTOM_RUNTIME)
class TestDotNetCoreRuntimes(LambdaTestBase):
    @classmethod
    def setUpClass(cls):
        cls.lambda_client = aws_stack.connect_to_service('lambda')
        cls.zip_file_content2 = load_file(TEST_LAMBDA_DOTNETCORE2, mode='rb')
        cls.zip_file_content31 = load_file(TEST_LAMBDA_DOTNETCORE31, mode='rb')
    def __run_test(self, func_name, zip_file, handler, runtime, expected_lines):
        if not use_docker():
            return
        testutil.create_lambda_function(
            func_name=func_name,
            zip_file=zip_file,
            handler=handler,
            runtime=runtime)
        result = self.lambda_client.invoke(FunctionName=func_name, Payload=b'{}')
        result_data = result['Payload'].read()
        self.assertEqual(result['StatusCode'], 200)
        self.assertEqual(to_str(result_data).strip(), '{}')
        
        
        testutil.delete_lambda_function(func_name)
    def test_dotnetcore2_lambda_running_in_docker(self):
        self.__run_test(
            func_name=TEST_LAMBDA_NAME_DOTNETCORE2,
            zip_file=self.zip_file_content2,
            handler='DotNetCore2::DotNetCore2.Lambda.Function::SimpleFunctionHandler',