I'm amused by the off-hand note about maybe using DynamoDB instead of a relational database, because the biggest issue with connecting your Lambda functions to

I'm amused by the off-hand note about maybe using DynamoDB instead of a relational database, because the biggest issue with connecting your Lambda functions to MySQL is that using Lambdas within a VPC is absolutely terrible right now. Sure, you can make lambda IP subnets in your VPC, assign your lambda to a subnet, give it a security group, and then you can easily setup your security group rules for your lambdas to connect. It's quite snazzy! Until you realize that cold startup times for your lambda normally are around a second, and when you have it running in your VPC, it takes 5 more seconds for it to make the VPC network interface. If you're using lambdas to make a REST API, this turns an occasional slight slowdown to a complete show stopper for your users. There doesn't appear to be any good solution to this right now. You can host your Lambda outside the VPC, but then you essentially need to open your MySQL security group to the world (or every AWS Subnet, which is about the same thing). You can make a request to your Lambda function every 15 minutes, which is a terrible hack but works, except when you start approaching 50+ lambda functions you have to make heartbeat requests to every 15 minutes. The issue is somewhat mitigated if, instead of leaning towards the natural inclination to make a separate Lambda function for each possible API request, you group API requests together, or use one Lambda function for your entire need. If your service is small in scope anyway, it won't particularly affect performance, and there will be less likelihood the lambda will go dormant/less functions you need to make heartbeat requests to. Serverless Framework has a good overview of the coding pattern options: https://serverless.com/blog/serverless-architecture-code-patterns/ https://serverless.com/blog/serverless-architecture-code-pat... And yes, if you just jump straight from traditional server architectures straight to Lambda functions and Dynamodb NoSQL, you don't need VPC connections to connect to Database servers. But some of us change architecture paradigms one step at a time, Amazon!