I've just started using DynamoDB on a project. Before I made the choice, I discussed some architecture issues with a friend who works at a big fast growing unic

I've just started using DynamoDB on a project. Before I made the choice, I discussed some architecture issues with a friend who works at a big fast growing unicorn start-up. They use MongoDB for the majority of the app the user sees, they use ElasticSearch for search, postgres for reporting. Data gets exported or updated in the data-sources that best suit the need of that data, rather than trying to find a single data solution that fits every use of the data.