Ariadne vs GraphQL Kotlin

Ariadne is an open-source Python library for building GraphQL APIs with a schema-first design. Developers describe an API using GraphQL Schema Definition Language and connect schema fields to application logic with resolver functions. The server supports asynchronous and synchronous query execution and can be served through WSGI or ASGI apps. The project describes interoperability with web frameworks and includes a Django integration example. Ariadne Codegen creates a typed Python client and Pydantic models from a GraphQL schema and operations; generated client results are validated against those models at runtime. An optional SQLAlchemy 2.0 integration supports synchronous sessions in WSGI and ASGI, while AsyncSession is limited to ASGI and has a documented limitation involving sibling root fields. Ariadne implements the GraphQL multipart request specification for uploads. Its default Upload scalar is write-only and supports values passed through variables. Security documentation discusses denial-of-service and credential-leakage risks and gives mitigation guidance. Ariadne is self-hosted and free, and the site lists Linux, web, and API platforms.

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.