Amazon AppSync vs GraphQL Kotlin
Amazon AppSync
aws.amazon.comGraphQL Kotlin
opensource.expediagroup.comSide by side
| Figure | Amazon AppSync | GraphQL Kotlin |
|---|---|---|
| Price from | $1/mo | Free |
| Free plan | — | Yes |
| Free trial | — | — |
| Open source | — | — |
| Web | Yes | — |
| API | Yes | Yes |
| Self-hosted | — | Yes |
| Plans published | 2 | 1 |
| Spec score · GraphQL Tools | 7.8 (#10) | 8.0 (#8) |
| Federation | AppSync Merged GraphQL APIs combine schemas, data sources, and resolvers from multiple source APIs into one endpoint. | The federation module can generate Apollo Federation compliant schemas. |
| Intended users | AWS describes AppSync as suitable for connecting application developers to data and building experiences such as AI gateways, federated APIs, and real-time applications. | The project describes its common use cases as running a GraphQL server and generating a type-safe client in Kotlin. |
| Purpose | AWS AppSync connects applications to events, data, and AI models through GraphQL and pub/sub APIs. | GraphQL Kotlin is a collection of libraries built on graphql-java to run GraphQL clients and servers in Kotlin. |
| Support | AWS offers support tailored to needs ranging from startups to enterprise level through its contact-an-expert option. | The maintainers invite questions through GitHub Discussions and the public #graphql-kotlin channel on Kotlin Slack. |
Plans
In their own words
Amazon AppSync
Amazon AppSync has no write-up on Specifiction yet; its figures are above.
GraphQL Kotlin
GraphQL Kotlin is a free Apache License 2.0 collection of libraries, built on graphql-java, for running GraphQL clients and servers in Kotlin. Its schema generator creates schemas from Kotlin code, and a federation module can produce Apollo Federation-compliant schemas. Gradle and Maven plugins generate type-safe Kotlin clients from existing schemas. Generated clients support queries, mutations, batching, coroutines, custom scalars, configurable enum defaults, and Jackson or kotlinx.serialization models. Reference HTTP integrations use Ktor HTTP Client and Spring WebClient, while custom engines are possible. Server implementations target Spring Boot and Ktor; the Spring server uses Spring WebFlux. Ktor supports Kotlin Flow subscriptions over WebSockets with the graphql-transport-ws subprotocol. Its plugin leaves route configuration to the application, allowing selective routes and added authentication logic. The schema generator supports Kotlin Lists, but Sets, arbitrary Maps, and arrays are not supported out of the box. The project is self-hosted, with security guidance in its repository and community support through GitHub Discussions and Kotlin Slack.