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If you didn't hear @Werner talk about the CDK in his keynote earlier, listen in ( https://pages.awscloud.com/aws-summit-online-keynote-EN.html) The CDK is hugely interesting for a number of reasons (starting with the fact that while it's ostensibly an @awscloud project, ~50% of contributions come from outside AWS)
The CDK could very well become the framework of the future for cloud development...because it's much bigger than one company's project. First, I love the existing/proposed "forks": CDK8s and tfcdk from @HashiCorp. Oh, and CDK for Azure to to create Azure infra? Of course you can!
"The construct API design lends itself to easily represent a number of data models in the Infastructure as Code space, including CloudFormation (the original design), Kubernetes, and Terraform" says @mattbonig https://www.jeffersonfrank.com/aws-blog/ask-the-expert-aws-cdk/
It's easy to see how the CDK can help make it easier to run open source in the cloud (e.g., quickly deploy the LAMP stack).
Or, as @094459 puts it, look at JSII, which "allows anyone who creates a code base to generate multiple language bindings â so you might create something in java, but it then will generate typescript, c#, python equivs" (also see https://www.matthewbonig.com/2020/01/11/creating-constructs/)
I love the CDK. I love it both because of what it means for AWS and those who want to build with us, but I love it just as much for what it means for those who want to build with Azure, Hashi, etc. It's a great example of the potential unleashed by open source
Oh, and here's the link to the CDK 
https://aws.amazon.com/cdk/
https://aws.amazon.com/cdk/
