After gathering more specific requirements, evaluating limitations, we started preparing the architecture design proposal. The process included AWS components evaluation, Spikes, and PoCs, and finally brought as to the design, which was as per above attached scheme.
We proposed a Serverless solution based on DynamoDB, Lambdas, SQS, SNS, CloudWatch. After the acceptance of the proposed concept, we have developed MVP and delivered it to the AWS Infrastructure. Working MVP was successfully tested on the AWS environment against defined use cases and workloads.