> GraphQL server library for Rust [](https://dev.azure.com/graphql-rust/GraphQL%20Rust/_build/latest?definitionId=1) [](https://codecov.io/gh/graphql-rust/juniper) [](https://crates.io/crates/juniper) [](https://gitter.im/juniper-graphql/Lobby) --- [GraphQL][graphql] is a data query language developed by Facebook intended to serve mobile and web application frontends. _Juniper_ makes it possible to write GraphQL servers in Rust that are type-safe and blazingly fast. We also try to make declaring and resolving GraphQL schemas as convenient as Rust will allow. Juniper does not include a web server - instead it provides building blocks to make integration with existing servers straightforward. It optionally provides a pre-built integration for the [Actix][actix], [Hyper][hyper], [Rocket], and [Warp][warp] frameworks, including embedded [Graphiql][graphiql] and [GraphQL Playground][playground] for easy debugging. - [Cargo crate](https://crates.io/crates/juniper) - [API Reference][docsrs] - [Book][book]: Guides and Examples ([current][book] | [master][book_master]) The book is also available for the master branch and older versions published after 0.11.1. See the [book index][book_index]. ## Getting Started The best place to get started is the [Juniper Book][book], which contains guides with plenty of examples, covering all features of Juniper. (very much WIP) To get started quickly and get a feel for Juniper, check out the [Quickstart][book_quickstart] section. For specific information about macros, types and the Juniper api, the [API Reference][docsrs] is the best place to look. You can also check out the [Star Wars schema][test_schema_rs] to see a complex example including polymorphism with traits and interfaces. For an example of web framework integration, see the [actix][actix_examples], [axum][axum_examples], [hyper][hyper_examples], [rocket][rocket_examples], and [warp][warp_examples] examples folders. ## Features Juniper supports the full GraphQL query language according to the [specification (October 2021)][graphql_spec], including interfaces, unions, schema introspection, and validations. It can also output the schema in the [GraphQL Schema Language][schema_language]. As an exception to other GraphQL libraries for other languages, Juniper builds non-null types by default. A field of type `Vec` will be converted into `[Episode!]!`. The corresponding Rust type for e.g. `[Episode]` would be `Option>>`. Juniper is agnostic to serialization format and network transport. Juniper supports both asynchronous and synchronous execution using `execute()` and `execute_sync()` respectively. Asynchronous execution is runtime agnostic. Juniper follows a [code-first approach][schema_approach] to defining GraphQL schemas. If you would like to use a [schema-first approach][schema_approach] instead, consider [juniper-from-schema][] for generating code from a schema file. ## Integrations ### Data types Juniper has automatic integration with some very common Rust crates to make building schemas a breeze. The types from these crates will be usable in your Schemas automatically. - [uuid][uuid] - [url][url] - [chrono][chrono] - [chrono-tz][chrono-tz] - [time][time] - [bson][bson] ### Web Frameworks - [actix][actix] - [axum][axum] - [hyper][hyper] - [rocket][rocket] - [warp][warp] ## Guides & Examples - [Juniper + actix-web example](https://github.com/actix/examples/tree/master/graphql/juniper) ## API Stability Juniper has not reached 1.0 yet, thus some API instability should be expected. [actix]: https://actix.rs/ [axum]: https://docs.rs/axum [graphql]: http://graphql.org [graphiql]: https://github.com/graphql/graphiql [playground]: https://github.com/prisma/graphql-playground [graphql_spec]: https://spec.graphql.org/October2021 [schema_language]: https://graphql.org/learn/schema/#type-language [schema_approach]: https://blog.logrocket.com/code-first-vs-schema-first-development-graphql/ [test_schema_rs]: https://github.com/graphql-rust/juniper/blob/master/juniper/src/tests/fixtures/starwars/schema.rs [tokio]: https://github.com/tokio-rs/tokio [actix_examples]: https://github.com/graphql-rust/juniper/tree/master/juniper_actix/examples [axum_examples]: https://github.com/graphql-rust/juniper/tree/master/juniper_axum/examples [hyper_examples]: https://github.com/graphql-rust/juniper/tree/master/juniper_hyper/examples [rocket_examples]: https://github.com/graphql-rust/juniper/tree/master/juniper_rocket/examples [hyper]: https://hyper.rs [rocket]: https://rocket.rs [book]: https://graphql-rust.github.io [book_master]: https://graphql-rust.github.io/juniper/master [book_index]: https://graphql-rust.github.io [book_quickstart]: https://graphql-rust.github.io/quickstart.html [docsrs]: https://docs.rs/juniper [warp]: https://github.com/seanmonstar/warp [warp_examples]: https://github.com/graphql-rust/juniper/tree/master/juniper_warp/examples [uuid]: https://crates.io/crates/uuid [url]: https://crates.io/crates/url [chrono]: https://crates.io/crates/chrono [chrono-tz]: https://crates.io/crates/chrono-tz [time]: https://crates.io/crates/time [bson]: https://crates.io/crates/bson [juniper-from-schema]: https://github.com/davidpdrsn/juniper-from-schema