A software engineer is developing a web App using Sinatra, which is a free and open-source software web application library and domain-specific language written in Ruby. He wants to develop that in AWS Elastic Beanstalk. However, it seems that Sinatra is not a supported built-in platform that can be used. He does not want to use docker either for this. Can he create a customized environment for the App in Elastic Beanstalk? Choose 2 options.

Answer options:

A.No. He cannot create the Sinatra app in Elastic Beanstalk as only the Platforms published and maintained by AWS Elastic Beanstalk are supported. He should use the Docker platform.
B.Yes, He can build a custom AMI in advance with Sinatra installed and configured on it. Create an ElasticBeanStalk environment and then modify the EC2 image ID with the customized AMI.
C.Yes. He can create his own platforms on Ubuntu, Red Hat Enterprise, or Amazon Linux and customize his instances with Sinatra. A Packer template will be used. When creating an Elastic Beanstalk environment, select the customized platform.
D.Yes. He can create his own platforms on Amazon Linux and customize his instances using docker. A Dockerfile will be used together with other scripts. When creating an Elastic Beanstalk environment, select the customized docker platform.

Correct Answer: B and C
Elastic Beanstalk supports custom platforms now. A custom platform lets you develop an entirely new platform from scratch, customizing the operating system, additional software, and scripts that Elastic Beanstalk runs on platform instances.
The custom image can be built from one of the supported operating systems of Ubuntu, RHEL, or Amazon Linux. In order to simplify the creation of these specialized Elastic Beanstalk platforms, machine images are now created using the Packer tool.
Refer to the technical blog https://aws.amazon.com/blogs/aws/launch-aws-elastic-beanstalk-launches-support-for-custom-platforms/ on how to set up a customer platform.
After setting up a customer platform, choose the new platform while creating a new environment.
Option A is incorrect. Because the customer platform is supported. Also, please note that Docker is another option that can work as well. However, this case disallows Docker.
Option B is Correct. 
Option C is CORRECT. Because it is a proper way to create a custom platform for Sinatra.
Option D is incorrect. Because creating a customer platform uses Packer rather than Docker as a tool to build up the AMI. In order to create the custom platform, the developer should start with a Packer template. A sample of a basic folder structure for building a platform definition archive looks as follows.