We haven't hit any scaling issues yet. GraphQL is nice. It's really about getting data directly from DynamoDB and Aurora to an end point that Android/iOS/React-JS can query and subscribe to. Apache Velocity Template Language that AppSync uses is a pain though. This post captures it well (unfortunately): https://www.reddit.com/r/graphql/comments/b0zomv/aws_appsync...

AppSync does have limitations we have to contend with. Custom scalar types cannot be defined hence we are not able to define strictly typed GeoJSON objects. Apache VTL has its own learning curve; once you master it you can implement functionality without leaning on invoking lambda functions and avoid paying for their usage in high volume GraphQl call scenarios and access queried data faster.

Just FYI, Hasura GraphQL Engine has native support for GeoJSON types:

https://blog.hasura.io/graphql-and-geo-location-on-postgres-...

PS: I work here. Apologies for plug.

I've been using Hasura for several months at work and it's approach to GraphQL has nailed the level of abstraction needed for early product development.

It's a great complement to serverless and static front-ends.