I am tackling a javascript challenge that has me stumped. Specifically, I am trying to figure out how to implement fine-grained authorization using an AWS serverless approach. In Spring security ACL, users can be banned from specific tasks at the instance level - for example, banning a user or role from commenting on a specific blog post. I want to replicate this functionality using JavaScript, Lambdas, and DynamoDB in AWS, but I am struggling to find a detailed design or open-source example to guide me. It would be incredibly helpful to see a Javascript or Typescript example to learn from, as those are the languages I am most comfortable with.