v3.3.0

## 🚀 New

- Add support for configuring the Regex engine on the router (#4254)
  Swap the compiler used for `regex()` route constraints. Assign a drop-in engine such as `coregex.MustCompile` for faster matching;Fiber reuses the compiled matcher across requests.
  ```go
  app := fiber.New(fiber.Config{
      RegexHandler: coregex.MustCompile, // default: regexp.MustCompile
  })
  ```
  https://docs.gofiber.io/api/fiber#regexhandler
- Host auth middleware  (#4199)
  New `hostauthorization` middleware that validates the incoming `Host` header against an allowlist (exact host, `.subdomain` wildcard, CIDR range) to protect against DNS rebinding attacks.
  ```go
  app.Use(hostauthorization.New(hostauthorization.Config{
      AllowedHosts: []string{"api.myapp.com", ".myapp.com", "10.0.0.0/8"},
  }))
  ```
  https://docs.gofiber.io/middleware/hostauthorization
- Delegate implementation to fasthttp/prefork (#4210)
  Prefork now delegates to fasthttp's `prefork` package and adds `PreforkRecoverThreshold` (max child restarts before the master exits) and `PreforkLogger` to `ListenConfig`.
  https://docs.gofiber.io/api/fiber#preforkrecoverthreshold
- Add support for contextual logs (#4241)
  Render request-scoped fields in `log.WithContext(c)` by configuring a template with `log.SetContextTemplate`, reusing the `middleware/logger` engine (including `${value:key}` for arbitrary context values).
  ```go
  log.MustSetContextTemplate(log.ContextConfig{Format: log.RequestIDFormat})

  app.Get("/", func(c fiber.Ctx) error {
      log.WithContext(c).Info("start") // renders the request id
      return c.SendString("ok")
  })
  ```
  https://docs.gofiber.io/api/log#bind-context
- Add storage backed SharedState for prefork applications (#4243)
A prefork-safe, storage-backed key/value store via `app.SharedState()` for data shared across workers/processes, with JSON/MsgPack/CBOR/XML helpers and automatic key namespacing. `app.State()` stays process-local.
  ```go
  app := fiber.New(fiber.Config{
      SharedStorage: redis.New(), // any fiber.Storage shared across workers
  })
  app.SharedState().SetJSON("config", cfg, 0)
  ```
  https://docs.gofiber.io/api/state#sharedstate-prefork-safe
- Add lightweight SSE middleware (#4239)
  A Fiber-native `middleware/sse` for Server-Sent Events: SSE headers, event/comment/retry frames, per-write flushing, heartbeats,
  `Last-Event-ID` access, and disconnect detection via `stream.Context()`.
  ```go
  app.Get("/events", sse.New(sse.Config{
      Handler: func(c fiber.Ctx, stream *sse.Stream) error {
          return stream.Event(sse.Event{Name: "message", Data: fiber.Map{"message": "hello"}})
      },
  }))
  ```
  https://docs.gofiber.io/middleware/sse

## 🧹 Updates

- Add prefixes to unexported boolean fields (#4300)
- Improve error messages in SaveFileToStorage (#4173)
- Streamline request handler selection and context management for improved performance (#4233)

## 🐛 Fixes

- Preserve mounted sub-app regex handler during mount prefixing (#4308)
- Trim only one trailing dot in host normalization (#4307)
- Reject oversized unknown-length adaptor request bodies (#4306)
- Fix compress middleware's shouldSkip method to avoid memory growth (#4284)
- Reject malformed host authorities in hostauthorization (#4293)
- Synchronize view reloads with template rendering (#4288)
- Avoid panic for non-struct listeners in TLS config discovery (#4305)
- Clear plaintext cookie when encryption fails (#4303)
- Fix regex route constraint parsing with literal > (#4292)
- Reject empty normalized host before dynamic matching (#4291)
- Preserve idempotency replay protection for oversized responses (#4287)
- Enforce CookieJar domain acceptance and host-only cookie matching (#4282)
- Avoid panic when reading released Fiber context values (#4271)
- Enforce static root for fs-backed directory serving (#4277)
- Prevent negative paginate start overflow (#4272)
- Prevent SharedState namespace key collisions (#4274)
- Copy FullURL string before returning pooled buffer (#4275)
- Enforce paginate sort allowlist when AllowedSorts is unset (#4276)
- Validate and safely apply workflow version updates (#4273)
- Close BodyStream in adaptor FiberHandler streaming path (#4267)
- Prevent panic when MsgPack is not configured (#4268)
- Keep IsFromLocal loopback-only and add unix-socket helper (#4270)
- Prevent panic when CBOR is not explicitly configured (#4269)
- Guard session logger tag against released middleware (#4265)
- Add X-Real-IP protection to Forward and DomainForward variants (#4261)
- Ensure BalancerForward overwrites X-Real-IP header (#4260)
- Add test coverage for multipart BodyLimit error handling (#4237)
- Improve error propagation in Express-style handler (#4250)
- Remove SSE Next and clarify SSE handler docs (#4247)
- BasicAuth verifier for unknown users (#4245)

## 🛠️ Maintenance

<details>
<summary>13 changes</summary>

- bump github.com/shamaton/msgpack/v3 from 3.1.1 to 3.1.2 (#4296)
- bump codecov/codecov-action from 6.0.0 to 6.0.1 (#4294)
- bump actions/add-to-project from 1.0.2 to 2.0.0 (#4256)
- bump github.com/shamaton/msgpack/v3 from 3.1.0 to 3.1.1 (#4281)
- bump the golang-modules group with 3 updates (#4278)
- bump golang.org/x/sys from 0.43.0 to 0.44.0 in the golang-modules group (#4262)
- bump DavidAnson/markdownlint-cli2-action from 23.1.0 to 23.2.0 (#4259)
- bump benchmark-action/github-action-benchmark from 1.22.0 to 1.22.1 (#4258)
- bump github.com/valyala/fasthttp from 1.70.0 to 1.71.0 in the fasthttp-modules group (#4255)
- bump github.com/klauspost/compress from 1.18.5 to 1.18.6 (#4249)
- bump DavidAnson/markdownlint-cli2-action from 23.0.0 to 23.1.0 (#4246)
- bump github.com/mattn/go-isatty from 0.0.21 to 0.0.22 (#4242)
</details>

## 📚 Documentation

- Fix invalid RouteChain method chaining example (#4304)
- Harden reverse proxy X-Forwarded-For example (#4266)
- Correct fasthttpctx Done semantics in context guide (#4264)
- Clarify ${bytesSent} behavior in logger middleware (#4251)
- Clarify prefork security model and OS-specific socket behavior (#4240)

**📒 Documentation**: https://docs.gofiber.io/next/

**💬 Discord**: https://gofiber.io/discord

**Full Changelog**: https://github.com/gofiber/fiber/compare/v3.2.0...v3.3.0

Thank you @ReneWerner87, @elton-peixoto-lu, @gaby, @gtoxlili, @lyyvalhalla, @mutantkeyboard, @pageton and @pratikramteke for making this release possible.