I often see ppl adopt one of two development patterns:
1. Locally mock all the services that your Lambda function uses. Like API Gateway, SNS, SQS, etc. This is hard to do. If you are using a tool that mocks a specific service (like API Gateway), you won't be able to test a Lambda that's invoked by a different service (like SNS). On the other hand a service like LocalStack, that tries to mock a whole suite of services, is slow and the mocked services can be out of date.
2. Or, you'll need to deploy your changes to test them. Each deployment can take at least a minute. And repeatedly deploying to test a change really slows down the feedback loop.
SST lets you develop your Lambda functions locally while connecting to others AWS services without needing to mock them locally. Behind the scene, the lambda requests are streamed to ur local, runs ur local function, response streamed back to Lambda. So you can iterate on ur function code without redeploying.
Think of your Lambda functions are Live Reloaded. You can see it in action here — https://youtu.be/hnTSTm5n11g
I’m the core maintainer of the project. And folks in our community are saying using SST feels like "working in the future" ;)
I'd love for you to give it a try. We are also a part of the YC W21.