This is a prototype project demonstrating that a performant, zero-cost Graphql layer is possible with AWS Lambda functions.

The lambda function is uses Golang and GqlGen. It uses Gin to serve the requests, and aws-lambda-go-api-proxy to proxy the request from API Gateway to Gin. The Graphql function is written in such a way that you can easily convert the code to a microservice with little to no effort.

• You get the ease of writing and deploying a lambda function. (Sam CLI, Serverless Framework, Apex Up, etc.)
• Can easily convert the lambda function to a standalone service, and can convert existing services to lambda easily
• Can easily test the endpoint with the playground endpoint offered by GqlGen
• You can utilize the benefits of API Gateway, such as rate limiting, throttling, Authorization, etc.
• Performant, since written in Golang
• Tiny cold start time
• Most of all, since AWS has a generous free tier for Lambda, in most cases you should be able to have a Graphql endpoint for free

• No way to do subscriptions
• and ... that's it? 🤔

AppSync is great for bootstrapping and fast development and in most cases, AppSync would be enough. It has plenty of features like:

• it integrates nicely with Amplify and can easily generate client code given an AppSync endpoint
• provides plenty of sample templates for multiple data sources
• provides authorization, such as integration with Cognito
• multiple convenient scalar types
• integration with X Ray
• Graphql generation wizard

and lots more

However, it is difficult to some things, like:

• debug AppSync resolvers
• connect to data sources not supported by AppSync (must make HTTP calls)
• do complex business logic
• do unit tests
• logging

AppSync also pretty much forces you to lock in from day one, and you can't really re-use any of the VTL templates. However, we can easily repurpose this project to a microservice. With AppSync, you don't get a full fledged language and all of its benefits, such as robust libraries, concurrency, etc.