(I’m from Hasura)
You can extend business logic in Hasura in a number of ways, including (but not exclusively) ones that work well with serverless and async architectures. Other examples follow:
1. You can extend it by adding business logic in the database via user-defined functions. Eg: You want a fulltext search or a PostGIS function that is better off in the DB anyway.
2. You can bring your own GraphQL server with custom resolvers and Hasura will merge them into its own API and let you “join” across them as well.
3. You can bring REST APIs and add graphql types for them in Hasura and use it as custom resolvers that extend the schema as well.
Hasura’s key value add is an instant GraphQL API backed by your own data-sources (database, GraphQL, REST) and then a fine-grained authorization system on it.
Like Nikolas said, very different from Prisma. Hasura aims to add value as “infrastructure” by guaranteeing performance and security where as Prisma is like an ORM/database toolkit.