This page shows how to add Sentry instrumentation to programs using the FastHTTP package.

For a quick reference, there is a complete example available directly at the Go SDK source code repository.

GoDoc-style API documentation is also available.


go get
import (

	sentryfasthttp ""

// To initialize Sentry's handler, you need to initialize Sentry itself beforehand
if err := sentry.Init(sentry.ClientOptions{
	Dsn: "",
	EnableTracing: true,
	// Set TracesSampleRate to 1.0 to capture 100%
	// of transactions for performance monitoring.
	// We recommend adjusting this value in production,
	TracesSampleRate: 1.0,
}); err != nil {
	fmt.Printf("Sentry initialization failed: %v\n", err)

// Create an instance of sentryfasthttp
sentryHandler := sentryfasthttp.New(sentryfasthttp.Options{})

// After creating the instance, you can attach the handler as one of your middleware
fastHTTPHandler := sentryHandler.Handle(func(ctx *fasthttp.RequestCtx) {
	panic("y tho")

fmt.Println("Listening and serving HTTP on :3000")

// And run it
if err := fasthttp.ListenAndServe(":3000", fastHTTPHandler); err != nil {


sentryfasthttp accepts a struct of Options that allows you to configure how the handler will behave.

Currently, it respects three options:

// Repanic configures whether Sentry should repanic after recovery, in most cases, it defaults to false,
// as fasthttp doesn't include its own Recovery handler.
Repanic bool
// WaitForDelivery configures whether you want to block the request before moving forward with the response.
// Because fasthttp doesn't include its own `Recovery` handler, it will restart the application,
// and the event won't be delivered otherwise.
WaitForDelivery bool
// Timeout for the event delivery requests.
Timeout time.Duration


sentryfasthttp attaches an instance of *sentry.Hub ( to the request's context, which makes it available throughout the rest of the request's lifetime. You can access it by using the sentryfasthttp.GetHubFromContext() method on the context itself in any of your proceeding middleware and routes. And it should be used instead of the global sentry.CaptureMessage, sentry.CaptureException, or any other calls, as it keeps the separation of data between the requests.

Keep in mind that *sentry.Hub won't be available in middleware attached before sentryfasthttp!

func enhanceSentryEvent(handler fasthttp.RequestHandler) fasthttp.RequestHandler {
	return func(ctx *fasthttp.RequestCtx) {
		if hub := sentryfasthttp.GetHubFromContext(ctx); hub != nil {
			hub.Scope().SetTag("someRandomTag", "maybeYouNeedIt")

// Later in the code
sentryHandler := sentryfasthttp.New(sentryfasthttp.Options{
	Repanic: true,
	WaitForDelivery: true,

defaultHandler := func(ctx *fasthttp.RequestCtx) {
	if hub := sentryfasthttp.GetHubFromContext(ctx); hub != nil {
		hub.WithScope(func(scope *sentry.Scope) {
			scope.SetExtra("unwantedQuery", "someQueryDataMaybe")
			hub.CaptureMessage("User provided unwanted query string, but we recovered just fine")

fooHandler := enhanceSentryEvent(func(ctx *fasthttp.RequestCtx) {
	panic("y tho")

fastHTTPHandler := func(ctx *fasthttp.RequestCtx) {
	switch string(ctx.Path()) {
	case "/foo":

fmt.Println("Listening and serving HTTP on :3000")

if err := fasthttp.ListenAndServe(":3000", sentryHandler.Handle(fastHTTPHandler)); err != nil {

Accessing Context in BeforeSend callback

	Dsn: "",
	BeforeSend: func(event *sentry.Event, hint *sentry.EventHint) *sentry.Event {
		if hint.Context != nil {
			if ctx, ok := hint.Context.Value(sentry.RequestContextKey).(*fasthttp.RequestCtx); ok {
				// You have access to the original Context if it panicked
		return event
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