Fuego 🔥

The framework for busy Go developers

🚀 Explore and contribute to our 2025 Roadmap! 🚀

Production-ready Go API framework generating OpenAPI documentation from code. Inspired by Nest, built for Go developers.

Also empowers templating with html/template, a-h/templ and maragudk/gomponents: see the example running live.

Sponsors

Fuego is proudly sponsored by Zuplo, that provides a Fuego integration!

Zuplo allows you to secure your Fuego API, scale it globally, generate documentation from your OpenAPI, and monetize your users.

Why Fuego?

Chi, Gin, Fiber and Echo are great frameworks. But since they were designed a long time ago, their current API does not allow them to deduce OpenAPI types from signatures, things that are now possible with generics. Fuego offers a lot of "modern Go based" features that make it easy to develop APIs and web applications.

Features

• OpenAPI: Fuego automatically generates OpenAPI documentation from code - not from comments nor YAML files!
• 100% net/http compatible (no lock-in): Fuego is built on top of net/http, so you can use any http.Handler middleware or handler! Fuego also supports log/slog, context and html/template.
• Routing: Fuego router is based on Go 1.22 net/http, with grouping and middleware support
• Serialization/Deserialization: Fuego automatically serializes and deserializes JSON, XML and HTML Forms based on user-provided structs (or not, if you want to do it yourself)
• Validation: Fuego provides a simple and fast validator based on go-playground/validator
• Transformation: easily transform your data by implementing the fuego.InTransform and fuego.OutTransform interfaces - also useful for custom validation
• Middlewares: easily add a custom net/http middleware or use the provided middlewares.
• Error handling: Fuego provides centralized error handling with the standard RFC 9457.
• Rendering: Fuego provides a simple and fast rendering system based on html/template - you can still also use your own template system like templ or gomponents
• Adaptors: Fuego can be plugged to an existing Gin or Echo server to generate OpenAPI documentation

Examples

Hello World

package main

import "github.com/go-fuego/fuego"

func main() {
	s := fuego.NewServer()

	fuego.Get(s, "/", func(c fuego.ContextNoBody) (string, error) {
		return "Hello, World!", nil
	})

	s.Run()
}

Simple POST

package main

import "github.com/go-fuego/fuego"

type MyInput struct {
	Name string `json:"name" validate:"required"`
}

type MyOutput struct {
	Message string `json:"message"`
}

func main() {
	s := fuego.NewServer()

	// Automatically generates OpenAPI documentation for this route
	fuego.Post(s, "/user/{user}", myController)

	s.Run()
}

func myController(c fuego.ContextWithBody[MyInput]) (*MyOutput, error) {
	body, err := c.Body()
	if err != nil {
		return nil, err
	}

	return &MyOutput{Message: "Hello, " + body.Name}, nil
}

With transformation & custom validation

type MyInput struct {
	Name string `json:"name" validate:"required"`
}

// Will be called just before returning c.Body()
func (r *MyInput) InTransform(context.Context) error {
	r.Name = strings.ToLower(r.Name)

	if r.Name == "fuego" {
		return errors.New("fuego is not a valid name for this input")
	}

	return nil
}

More OpenAPI documentation

package main

import (
	"github.com/go-fuego/fuego"
	"github.com/go-fuego/fuego/option"
	"github.com/go-fuego/fuego/param"
)

func main() {
	s := fuego.NewServer()

	// Custom OpenAPI options
	fuego.Post(s, "/", myController,
		option.Description("This route does something..."),
		option.Summary("This is my summary"),
		option.Tags("MyTag"), // A tag is set by default according to the return type (can be deactivated)
		option.Deprecated(),  // Marks the route as deprecated in the OpenAPI spec

		option.Query("name", "Declares a query parameter with default value", param.Default("Carmack")),
		option.Header("Authorization", "Bearer token", param.Required()),
		optionPagination,
		optionCustomBehavior,
	)

	s.Run()
}

var optionPagination = option.Group(
	option.QueryInt("page", "Page number", param.Default(1), param.Example("1st page", 1), param.Example("42nd page", 42)),
	option.QueryInt("perPage", "Number of items per page"),
)

var optionCustomBehavior = func(r *fuego.BaseRoute) {
	r.XXX = "YYY"
}

Std lib compatibility

package main

import (
	"net/http"

	"github.com/go-fuego/fuego"
)

func main() {
	s := fuego.NewServer()

	// Standard net/http middleware
	fuego.Use(s, func(next http.Handler) http.Handler {
		return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
			w.Header().Set("X-Hello", "World")
			next.ServeHTTP(w, r)
		})
	})

	// Standard net/http handler with automatic OpenAPI route declaration
	fuego.GetStd(s, "/std", func(w http.ResponseWriter, r *http.Request) {
		w.Write([]byte("Hello, World!"))
	})

	s.Run()
}

Real-world examples

Please see the /examples folder for more examples.

• Simple CRUD with OpenAPI
• Full app with HTML rendering

All features

package main

import (
	"context"
	"errors"
	"net/http"
	"strings"

	chiMiddleware "github.com/go-chi/chi/v5/middleware"
	"github.com/go-fuego/fuego"
	"github.com/rs/cors"
)

type Received struct {
	Name string `json:"name" validate:"required"`
}

type MyResponse struct {
	Message       string `json:"message"`
	BestFramework string `json:"best"`
}

func main() {
	s := fuego.NewServer(
		fuego.WithAddr("localhost:8088"),
	)

	fuego.Use(s, cors.Default().Handler)
	fuego.Use(s, chiMiddleware.Compress(5, "text/html", "text/css"))

	// Fuego 🔥 handler with automatic OpenAPI generation, validation, (de)serialization and error handling
	fuego.Post(s, "/", func(c fuego.ContextWithBody[Received]) (MyResponse, error) {
		data, err := c.Body()
		if err != nil {
			return MyResponse{}, err
		}

		c.Response().Header().Set("X-Hello", "World")

		return MyResponse{
			Message:       "Hello, " + data.Name,
			BestFramework: "Fuego!",
		}, nil
	})

	// Standard net/http handler with automatic OpenAPI route declaration
	fuego.GetStd(s, "/std", func(w http.ResponseWriter, r *http.Request) {
		w.Write([]byte("Hello, World!"))
	})

	s.Run()
}

// InTransform will be called when using c.Body().
// It can be used to transform the entity and raise custom errors
func (r *Received) InTransform(context.Context) error {
	r.Name = strings.ToLower(r.Name)
	if r.Name == "fuego" {
		return errors.New("fuego is not a name")
	}
	return nil
}

// OutTransform will be called before sending data
func (r *MyResponse) OutTransform(context.Context) error {
	r.Message = strings.ToUpper(r.Message)
	return nil
}

curl http://localhost:8088/std
# Hello, World!
curl http://localhost:8088 -X POST -d '{"name": "Your Name"}' -H 'Content-Type: application/json'
# {"message":"HELLO, YOUR NAME","best":"Fuego!"}
curl http://localhost:8088 -X POST -d '{"name": "Fuego"}' -H 'Content-Type: application/json'
# {"error":"cannot transform request body: cannot transform request body: fuego is not a name"}

From net/http to Fuego in 10s

net.http.to.Fuego.mov

Views

Before

After

Diff

Benefits of using Fuego views (controllers returning HTML)

• Never forget to return after an error
• OpenAPI schema generated, listing all the routes
• Deserialization and validation are easier
• Transition to Fuego is easy and fast

Contributing

See the contributing guide. Thanks to everyone who has contributed to this project! ❤️

Made with contrib.rocks

Roadmap

See the board.

Disclaimer for experienced gophers

I know you might prefer to use net/http directly, but if having a frame can convince my company to use Go instead of Node, I'm happy to use it.

License

MIT