GraphQLin

GraphQLin is an open-source data query language and runtime designed to query and mutate graph-structured data across heterogeneous data sources through a single, strongly typed schema. While inspired by GraphQL, GraphQLin introduces features aimed at multi-source federation, incremental resolution, and streaming delivery, making it suitable for large, distributed datasets.

Core concepts include a schema-first approach, with type definitions for entities and relationships; resolvers that fetch data from adapters; and directives for access control and field-level transformations. Queries use a selection syntax comparable to GraphQL, with support for fragments, variables, and nested relationships. A federation layer composes multiple adapters into a unified graph. The runtime can deliver incremental results as individual fields resolve, and supports real-time subscriptions for live updates.

Architecture and components: a query planner that analyzes a request and creates an execution plan, adapters that connect to SQL, NoSQL, REST, or messaging systems, and a caching layer that can store partial results. GraphQLin provides a plugin ecosystem for authentication, tracing, and deployment in cloud or on-prem environments.

History: The project was proposed in 2020 by the GraphQLin Initiative and released in its first public version in 2021. Since then, it has evolved through several minor releases and community governance, emphasizing compatibility with GraphQL tooling while offering federation and streaming capabilities.

Usage and reception: GraphQLin has a niche but growing community, with early adopters in data integration, fintech, and healthcare where federated access to heterogeneous data sources is advantageous. It is commonly used as a complement to standard GraphQL services to unify multiple backends under a single query interface.

Example: Example query: query { person(id: "42") { id, name, employment { company { name } role } } }