Update to version 3.9.6

examples/AsyncResponseStream/AsyncResponseStream.ino

@@ -1,5 +1,5 @@
 // SPDX-License-Identifier: LGPL-3.0-or-later
-// Copyright 2016-2025 Hristo Gochkov, Mathieu Carbou, Emil Muratov
+// Copyright 2016-2026 Hristo Gochkov, Mathieu Carbou, Emil Muratov, Will Miles
 
 #include <DNSServer.h>
 #if defined(ESP32) || defined(LIBRETINY)
@@ -20,7 +20,7 @@ static AsyncWebServer server(80);
 void setup() {
   Serial.begin(115200);
 
-#if SOC_WIFI_SUPPORTED || CONFIG_ESP_WIFI_REMOTE_ENABLED || LT_ARD_HAS_WIFI
+#if ASYNCWEBSERVER_WIFI_SUPPORTED
   WiFi.mode(WIFI_AP);
   WiFi.softAP("esp-captive");
 #endif

examples/AsyncTunnel/AsyncTunnel.ino

@@ -1,5 +1,5 @@
 // SPDX-License-Identifier: LGPL-3.0-or-later
-// Copyright 2016-2025 Hristo Gochkov, Mathieu Carbou, Emil Muratov
+// Copyright 2016-2026 Hristo Gochkov, Mathieu Carbou, Emil Muratov, Will Miles
 
 //
 // Shows how to trigger an async client request from a browser request and send the client response back to the browser through websocket
@@ -70,7 +70,7 @@ static const size_t htmlContentLength = strlen_P(htmlContent);
 void setup() {
   Serial.begin(115200);
 
-#if SOC_WIFI_SUPPORTED || CONFIG_ESP_WIFI_REMOTE_ENABLED || LT_ARD_HAS_WIFI
+#if ASYNCWEBSERVER_WIFI_SUPPORTED
   WiFi.begin(WIFI_SSID, WIFI_PASSWORD);
   while (WiFi.status() != WL_CONNECTED) {
     delay(500);

examples/Auth/Auth.ino

@@ -1,5 +1,5 @@
 // SPDX-License-Identifier: LGPL-3.0-or-later
-// Copyright 2016-2025 Hristo Gochkov, Mathieu Carbou, Emil Muratov
+// Copyright 2016-2026 Hristo Gochkov, Mathieu Carbou, Emil Muratov, Will Miles
 
 //
 // Authentication and authorization middlewares
@@ -29,30 +29,36 @@ static AsyncAuthenticationMiddleware basicAuthHash;
 static AsyncAuthenticationMiddleware digestAuth;
 static AsyncAuthenticationMiddleware digestAuthHash;
 
+static AsyncAuthenticationMiddleware bearerAuthSharedKey;
+static AsyncAuthenticationMiddleware bearerAuthJWT;
+
 // complex authentication which adds request attributes for the next middlewares and handler
 static AsyncMiddlewareFunction complexAuth([](AsyncWebServerRequest *request, ArMiddlewareNext next) {
-  if (!request->authenticate("user", "password")) {
+  if (request->authenticate("Mathieu", "password")) {
+    request->setAttribute("user", "Mathieu");
+  } else if (request->authenticate("Bob", "password")) {
+    request->setAttribute("user", "Bob");
+  } else {
     return request->requestAuthentication();
   }
 
-  // add attributes to the request for the next middlewares and handler
-  request->setAttribute("user", "Mathieu");
-  request->setAttribute("role", "staff");
-  if (request->hasParam("token")) {
-    request->setAttribute("token", request->getParam("token")->value().c_str());
+  if (request->getAttribute("user") == "Mathieu") {
+    request->setAttribute("role", "staff");
+  } else {
+    request->setAttribute("role", "user");
   }
 
   next();
 });
 
 static AsyncAuthorizationMiddleware authz([](AsyncWebServerRequest *request) {
-  return request->getAttribute("token") == "123";
+  return request->getAttribute("role") == "staff";
 });
 
 void setup() {
   Serial.begin(115200);
 
-#if SOC_WIFI_SUPPORTED || CONFIG_ESP_WIFI_REMOTE_ENABLED || LT_ARD_HAS_WIFI
+#if ASYNCWEBSERVER_WIFI_SUPPORTED
   WiFi.mode(WIFI_AP);
   WiFi.softAP("esp-captive");
 #endif
@@ -87,6 +93,36 @@ void setup() {
   digestAuthHash.setAuthFailureMessage("Authentication failed");
   digestAuthHash.setAuthType(AsyncAuthType::AUTH_DIGEST);
 
+  // bearer authentication with shared key
+  bearerAuthSharedKey.setAuthType(AsyncAuthType::AUTH_BEARER);
+  bearerAuthSharedKey.setToken("shared-secret-key");
+
+  // bearer authentication with a JWT token
+  bearerAuthJWT.setAuthType(AsyncAuthType::AUTH_BEARER);
+  bearerAuthJWT.setAuthentificationFunction([](AsyncWebServerRequest *request) {
+    const String &token = request->authChallenge();
+    // 1. decode base64 token
+    // 2. decrypt token
+    const String &decrypted = "...";  // TODO
+    // 3. validate token (check signature, expiration, etc)
+    bool valid = token == "<token>" || token == "<another token>";
+    if (!valid) {
+      return false;
+    }
+    // 4. extract user info from token and set request attributes
+    if (token == "<token>") {
+      request->setAttribute("user", "Mathieu");
+      request->setAttribute("role", "staff");
+      return true;  // return true if token is valid, false otherwise
+    }
+    if (token == "<another token>") {
+      request->setAttribute("user", "Bob");
+      request->setAttribute("role", "user");
+      return true;  // return true if token is valid, false otherwise
+    }
+    return false;
+  });
+
   // basic authentication method
   // curl -v -u admin:admin  http://192.168.4.1/auth-basic
   server
@@ -132,9 +168,9 @@ void setup() {
     .addMiddleware(&digestAuthHash);
 
   // test digest auth custom authorization middleware
-  // curl -v --digest -u user:password  http://192.168.4.1/auth-custom?token=123 => OK
-  // curl -v --digest -u user:password  http://192.168.4.1/auth-custom?token=456 => 403
-  // curl -v --digest -u user:FAILED  http://192.168.4.1/auth-custom?token=456 => 401
+  // curl -v --digest -u Mathieu:password  http://192.168.4.1/auth-custom => OK
+  // curl -v --digest -u Bob:password  http://192.168.4.1/auth-custom => 403
+  // curl -v --digest -u any:password  http://192.168.4.1/auth-custom => 401
   server
     .on(
       "/auth-custom", HTTP_GET,
@@ -148,6 +184,32 @@ void setup() {
     )
     .addMiddlewares({&complexAuth, &authz});
 
+  // Bearer authentication with a shared key
+  // curl -v -H "Authorization: Bearer shared-secret-key" http://192.168.4.1/auth-bearer-shared-key => OK
+  server
+    .on(
+      "/auth-bearer-shared-key", HTTP_GET,
+      [](AsyncWebServerRequest *request) {
+        request->send(200, "text/plain", "Hello, world!");
+      }
+    )
+    .addMiddleware(&bearerAuthSharedKey);
+
+  // Bearer authentication with a JWT token
+  // curl -v -H "Authorization: Bearer <token>" http://192.168.4.1/auth-bearer-jwt => OK
+  // curl -v -H "Authorization: Bearer <another token>" http://192.168.4.1/auth-bearer-jwt => 403 Forbidden
+  // curl -v -H "Authorization: Bearer invalid-token" http://192.168.4.1/auth-bearer-jwt => 401 Unauthorized
+  server
+    .on(
+      "/auth-bearer-jwt", HTTP_GET,
+      [](AsyncWebServerRequest *request) {
+        Serial.println("User: " + request->getAttribute("user"));
+        Serial.println("Role: " + request->getAttribute("role"));
+        request->send(200, "text/plain", "Hello, world!");
+      }
+    )
+    .addMiddlewares({&bearerAuthJWT, &authz});
+
   server.begin();
 }
 

examples/CORS/CORS.ino

@@ -1,5 +1,5 @@
 // SPDX-License-Identifier: LGPL-3.0-or-later
-// Copyright 2016-2025 Hristo Gochkov, Mathieu Carbou, Emil Muratov
+// Copyright 2016-2026 Hristo Gochkov, Mathieu Carbou, Emil Muratov, Will Miles
 
 //
 // How to use CORS middleware
@@ -25,7 +25,7 @@ static AsyncCorsMiddleware cors;
 void setup() {
   Serial.begin(115200);
 
-#if SOC_WIFI_SUPPORTED || CONFIG_ESP_WIFI_REMOTE_ENABLED || LT_ARD_HAS_WIFI
+#if ASYNCWEBSERVER_WIFI_SUPPORTED
   WiFi.mode(WIFI_AP);
   WiFi.softAP("esp-captive");
 #endif

examples/CaptivePortal/CaptivePortal.ino

@@ -1,5 +1,5 @@
 // SPDX-License-Identifier: LGPL-3.0-or-later
-// Copyright 2016-2025 Hristo Gochkov, Mathieu Carbou, Emil Muratov
+// Copyright 2016-2026 Hristo Gochkov, Mathieu Carbou, Emil Muratov, Will Miles
 
 #include <DNSServer.h>
 #if defined(ESP32) || defined(LIBRETINY)
@@ -28,7 +28,7 @@ public:
     response->print("<!DOCTYPE html><html><head><title>Captive Portal</title></head><body>");
     response->print("<p>This is our captive portal front page.</p>");
     response->printf("<p>You were trying to reach: http://%s%s</p>", request->host().c_str(), request->url().c_str());
-#if SOC_WIFI_SUPPORTED || CONFIG_ESP_WIFI_REMOTE_ENABLED || LT_ARD_HAS_WIFI
+#if ASYNCWEBSERVER_WIFI_SUPPORTED
     response->printf("<p>Try opening <a href='http://%s'>this link</a> instead</p>", WiFi.softAPIP().toString().c_str());
 #endif
     response->print("</body></html>");
@@ -41,7 +41,7 @@ void setup() {
   Serial.println();
   Serial.println("Configuring access point...");
 
-#if SOC_WIFI_SUPPORTED || CONFIG_ESP_WIFI_REMOTE_ENABLED || LT_ARD_HAS_WIFI
+#if ASYNCWEBSERVER_WIFI_SUPPORTED
   if (!WiFi.softAP("esp-captive")) {
     Serial.println("Soft AP creation failed.");
     while (1);

examples/CatchAllHandler/CatchAllHandler.ino

@@ -1,5 +1,5 @@
 // SPDX-License-Identifier: LGPL-3.0-or-later
-// Copyright 2016-2025 Hristo Gochkov, Mathieu Carbou, Emil Muratov
+// Copyright 2016-2026 Hristo Gochkov, Mathieu Carbou, Emil Muratov, Will Miles
 
 //
 // Shows how to catch all requests and send a 404 Not Found response
@@ -86,7 +86,7 @@ static const size_t htmlContentLength = strlen_P(htmlContent);
 void setup() {
   Serial.begin(115200);
 
-#if SOC_WIFI_SUPPORTED || CONFIG_ESP_WIFI_REMOTE_ENABLED || LT_ARD_HAS_WIFI
+#if ASYNCWEBSERVER_WIFI_SUPPORTED
   WiFi.mode(WIFI_AP);
   WiFi.softAP("esp-captive");
 #endif

examples/ChunkResponse/ChunkResponse.ino

@@ -1,5 +1,5 @@
 // SPDX-License-Identifier: LGPL-3.0-or-later
-// Copyright 2016-2025 Hristo Gochkov, Mathieu Carbou, Emil Muratov
+// Copyright 2016-2026 Hristo Gochkov, Mathieu Carbou, Emil Muratov, Will Miles
 
 //
 // Chunk response with caching example
@@ -86,7 +86,7 @@ static const size_t htmlContentLength = strlen_P(htmlContent);
 void setup() {
   Serial.begin(115200);
 
-#if SOC_WIFI_SUPPORTED || CONFIG_ESP_WIFI_REMOTE_ENABLED || LT_ARD_HAS_WIFI
+#if ASYNCWEBSERVER_WIFI_SUPPORTED
   WiFi.mode(WIFI_AP);
   WiFi.softAP("esp-captive");
 #endif
@@ -94,11 +94,11 @@ void setup() {
   // first time: serves the file and cache headers
   // curl -N -v http://192.168.4.1/ --output -
   //
-  // secodn time: serves 304
+  // second time: serves 304
   // curl -N -v -H "if-none-match: 4272" http://192.168.4.1/ --output -
   //
   server.on("/", HTTP_GET, [](AsyncWebServerRequest *request) {
-    String etag = String(htmlContentLength);
+    String etag = "\"" + String(htmlContentLength) + "\"";  // RFC9110: ETag must be enclosed in double quotes
 
     if (request->header(asyncsrv::T_INM) == etag) {
       request->send(304);

examples/ChunkRetryResponse/ChunkRetryResponse.ino

@@ -1,5 +1,5 @@
 // SPDX-License-Identifier: LGPL-3.0-or-later
-// Copyright 2016-2025 Hristo Gochkov, Mathieu Carbou, Emil Muratov
+// Copyright 2016-2026 Hristo Gochkov, Mathieu Carbou, Emil Muratov, Will Miles
 
 //
 // Shows how to wait in a chunk response for incoming data
@@ -19,12 +19,6 @@
 
 #include <ESPAsyncWebServer.h>
 
-#if __has_include("ArduinoJson.h")
-#include <ArduinoJson.h>
-#include <AsyncJson.h>
-#include <AsyncMessagePack.h>
-#endif
-
 static const char *htmlContent PROGMEM = R"(
 <!DOCTYPE html>
 <html>
@@ -96,7 +90,7 @@ static int key = -1;
 void setup() {
   Serial.begin(115200);
 
-#if SOC_WIFI_SUPPORTED || CONFIG_ESP_WIFI_REMOTE_ENABLED || LT_ARD_HAS_WIFI
+#if ASYNCWEBSERVER_WIFI_SUPPORTED
   WiFi.mode(WIFI_AP);
   WiFi.softAP("esp-captive");
 #endif
@@ -107,7 +101,7 @@ void setup() {
 
   server.addMiddleware(&requestLogger);
 
-#if __has_include("ArduinoJson.h")
+#if ASYNC_JSON_SUPPORT == 1
 
   //
   // HOW TO RUN THIS EXAMPLE:
@@ -174,7 +168,7 @@ void setup() {
           return 0;  // 0 means we are done
         }
 
-        // log_d("UART answered!");
+        // async_ws_log_d("UART answered!");
 
         String answer = "You typed: ";
         answer.concat((char)key);
@@ -193,10 +187,10 @@ void setup() {
     },
     NULL,  // upload handler is not used so it should be NULL
     [](AsyncWebServerRequest *request, uint8_t *data, size_t len, size_t index, size_t total) {
-      // log_d("Body: index: %u, len: %u, total: %u", index, len, total);
+      // async_ws_log_d("Body: index: %u, len: %u, total: %u", index, len, total);
 
       if (!index) {
-        // log_d("Start body parsing");
+        // async_ws_log_d("Start body parsing");
         request->_tempObject = new String();
         // cast request->_tempObject pointer to String and reserve total size
         ((String *)request->_tempObject)->reserve(total);
@@ -204,7 +198,7 @@ void setup() {
         request->client()->setRxTimeout(30);
       }
 
-      // log_d("Append body data");
+      // async_ws_log_d("Append body data");
       ((String *)request->_tempObject)->concat((const char *)data, len);
     }
   );
@@ -217,13 +211,13 @@ void setup() {
 void loop() {
   if (triggerUART.length() && key == -1) {
     Serial.println(triggerUART);
-    // log_d("Waiting for UART input...");
+    // async_ws_log_d("Waiting for UART input...");
     while (!Serial.available()) {
       delay(100);
     }
     key = Serial.read();
     Serial.flush();
-    // log_d("UART input: %c", key);
+    // async_ws_log_d("UART input: %c", key);
     triggerUART = emptyString;
   }
 }

examples/EndBegin/EndBegin.ino

@@ -1,5 +1,5 @@
 // SPDX-License-Identifier: LGPL-3.0-or-later
-// Copyright 2016-2025 Hristo Gochkov, Mathieu Carbou, Emil Muratov
+// Copyright 2016-2026 Hristo Gochkov, Mathieu Carbou, Emil Muratov, Will Miles
 
 //
 // https://github.com/ESP32Async/ESPAsyncWebServer/discussions/23
@@ -24,7 +24,7 @@ static AsyncWebServer server(80);
 void setup() {
   Serial.begin(115200);
 
-#if SOC_WIFI_SUPPORTED || CONFIG_ESP_WIFI_REMOTE_ENABLED || LT_ARD_HAS_WIFI
+#if ASYNCWEBSERVER_WIFI_SUPPORTED
   WiFi.mode(WIFI_AP);
   WiFi.softAP("esp-captive");
 #endif
@@ -39,6 +39,10 @@ void setup() {
 
   Serial.println("end()");
   server.end();
+
+  Serial.println("waiting before restarting server...");
+  delay(100);
+
   server.begin();
   Serial.println("begin() - run: curl -v http://192.168.4.1/ => should succeed");
 }

examples/Filters/Filters.ino

@@ -1,5 +1,5 @@
 // SPDX-License-Identifier: LGPL-3.0-or-later
-// Copyright 2016-2025 Hristo Gochkov, Mathieu Carbou, Emil Muratov
+// Copyright 2016-2026 Hristo Gochkov, Mathieu Carbou, Emil Muratov, Will Miles
 
 //
 // Shows how to use setFilter to route requests to different handlers based on WiFi mode
@@ -32,7 +32,7 @@ public:
     response->print("<!DOCTYPE html><html><head><title>Captive Portal</title></head><body>");
     response->print("<p>This is out captive portal front page.</p>");
     response->printf("<p>You were trying to reach: http://%s%s</p>", request->host().c_str(), request->url().c_str());
-#if SOC_WIFI_SUPPORTED || CONFIG_ESP_WIFI_REMOTE_ENABLED || LT_ARD_HAS_WIFI
+#if ASYNCWEBSERVER_WIFI_SUPPORTED
     response->printf("<p>Try opening <a href='http://%s'>this link</a> instead</p>", WiFi.softAPIP().toString().c_str());
 #endif
     response->print("</body></html>");
@@ -51,17 +51,17 @@ void setup() {
       "/", HTTP_GET,
       [](AsyncWebServerRequest *request) {
         Serial.println("Captive portal request...");
-#if SOC_WIFI_SUPPORTED || CONFIG_ESP_WIFI_REMOTE_ENABLED || LT_ARD_HAS_WIFI
+#if ASYNCWEBSERVER_WIFI_SUPPORTED
         Serial.println("WiFi.localIP(): " + WiFi.localIP().toString());
 #endif
         Serial.println("request->client()->localIP(): " + request->client()->localIP().toString());
 #if ESP_IDF_VERSION_MAJOR >= 5
-#if SOC_WIFI_SUPPORTED || CONFIG_ESP_WIFI_REMOTE_ENABLED || LT_ARD_HAS_WIFI
+#if ASYNCWEBSERVER_WIFI_SUPPORTED
         Serial.println("WiFi.type(): " + String((int)WiFi.localIP().type()));
 #endif
         Serial.println("request->client()->type(): " + String((int)request->client()->localIP().type()));
 #endif
-#if SOC_WIFI_SUPPORTED || CONFIG_ESP_WIFI_REMOTE_ENABLED || LT_ARD_HAS_WIFI
+#if ASYNCWEBSERVER_WIFI_SUPPORTED
         Serial.println(WiFi.localIP() == request->client()->localIP() ? "should be: ON_STA_FILTER" : "should be: ON_AP_FILTER");
         Serial.println(WiFi.localIP() == request->client()->localIP());
         Serial.println(WiFi.localIP().toString() == request->client()->localIP().toString());
@@ -77,17 +77,17 @@ void setup() {
       "/", HTTP_GET,
       [](AsyncWebServerRequest *request) {
         Serial.println("Website request...");
-#if SOC_WIFI_SUPPORTED || CONFIG_ESP_WIFI_REMOTE_ENABLED || LT_ARD_HAS_WIFI
+#if ASYNCWEBSERVER_WIFI_SUPPORTED
         Serial.println("WiFi.localIP(): " + WiFi.localIP().toString());
 #endif
         Serial.println("request->client()->localIP(): " + request->client()->localIP().toString());
 #if ESP_IDF_VERSION_MAJOR >= 5
-#if SOC_WIFI_SUPPORTED || CONFIG_ESP_WIFI_REMOTE_ENABLED || LT_ARD_HAS_WIFI
+#if ASYNCWEBSERVER_WIFI_SUPPORTED
         Serial.println("WiFi.type(): " + String((int)WiFi.localIP().type()));
 #endif
         Serial.println("request->client()->type(): " + String((int)request->client()->localIP().type()));
 #endif
-#if SOC_WIFI_SUPPORTED || CONFIG_ESP_WIFI_REMOTE_ENABLED || LT_ARD_HAS_WIFI
+#if ASYNCWEBSERVER_WIFI_SUPPORTED
         Serial.println(WiFi.localIP() == request->client()->localIP() ? "should be: ON_STA_FILTER" : "should be: ON_AP_FILTER");
         Serial.println(WiFi.localIP() == request->client()->localIP());
         Serial.println(WiFi.localIP().toString() == request->client()->localIP().toString());
@@ -113,7 +113,7 @@ void setup() {
   // dnsServer.stop();
   // WiFi.softAPdisconnect();
 
-#if SOC_WIFI_SUPPORTED || CONFIG_ESP_WIFI_REMOTE_ENABLED || LT_ARD_HAS_WIFI
+#if ASYNCWEBSERVER_WIFI_SUPPORTED
   WiFi.persistent(false);
   WiFi.begin("IoT");
   while (WiFi.status() != WL_CONNECTED) {

examples/FlashResponse/FlashResponse.ino

@@ -1,5 +1,5 @@
 // SPDX-License-Identifier: LGPL-3.0-or-later
-// Copyright 2016-2025 Hristo Gochkov, Mathieu Carbou, Emil Muratov
+// Copyright 2016-2026 Hristo Gochkov, Mathieu Carbou, Emil Muratov, Will Miles
 
 //
 // Shows how to serve a large HTML page from flash memory without copying it to heap in a temporary buffer
@@ -86,7 +86,7 @@ static const size_t htmlContentLength = strlen_P(htmlContent);
 void setup() {
   Serial.begin(115200);
 
-#if SOC_WIFI_SUPPORTED || CONFIG_ESP_WIFI_REMOTE_ENABLED || LT_ARD_HAS_WIFI
+#if ASYNCWEBSERVER_WIFI_SUPPORTED
   WiFi.mode(WIFI_AP);
   WiFi.softAP("esp-captive");
 #endif

examples/HeaderManipulation/HeaderManipulation.ino

@@ -1,5 +1,5 @@
 // SPDX-License-Identifier: LGPL-3.0-or-later
-// Copyright 2016-2025 Hristo Gochkov, Mathieu Carbou, Emil Muratov
+// Copyright 2016-2026 Hristo Gochkov, Mathieu Carbou, Emil Muratov, Will Miles
 
 //
 // Show how to manipulate headers in the request / response
@@ -33,7 +33,7 @@ AsyncHeaderFreeMiddleware headerFree;
 void setup() {
   Serial.begin(115200);
 
-#if SOC_WIFI_SUPPORTED || CONFIG_ESP_WIFI_REMOTE_ENABLED || LT_ARD_HAS_WIFI
+#if ASYNCWEBSERVER_WIFI_SUPPORTED
   WiFi.mode(WIFI_AP);
   WiFi.softAP("esp-captive");
 #endif

examples/Headers/Headers.ino

@@ -1,5 +1,5 @@
 // SPDX-License-Identifier: LGPL-3.0-or-later
-// Copyright 2016-2025 Hristo Gochkov, Mathieu Carbou, Emil Muratov
+// Copyright 2016-2026 Hristo Gochkov, Mathieu Carbou, Emil Muratov, Will Miles
 
 //
 // Query and send headers
@@ -24,7 +24,7 @@ static AsyncWebServer server(80);
 void setup() {
   Serial.begin(115200);
 
-#if SOC_WIFI_SUPPORTED || CONFIG_ESP_WIFI_REMOTE_ENABLED || LT_ARD_HAS_WIFI
+#if ASYNCWEBSERVER_WIFI_SUPPORTED
   WiFi.mode(WIFI_AP);
   WiFi.softAP("esp-captive");
 #endif

examples/Json/Json.ino

@@ -1,5 +1,5 @@
 // SPDX-License-Identifier: LGPL-3.0-or-later
-// Copyright 2016-2025 Hristo Gochkov, Mathieu Carbou, Emil Muratov
+// Copyright 2016-2026 Hristo Gochkov, Mathieu Carbou, Emil Muratov, Will Miles
 
 //
 // Shows how to send and receive Json data
@@ -19,27 +19,21 @@
 
 #include <ESPAsyncWebServer.h>
 
-#if __has_include("ArduinoJson.h")
-#include <ArduinoJson.h>
-#include <AsyncJson.h>
-#include <AsyncMessagePack.h>
-#endif
-
 static AsyncWebServer server(80);
 
-#if __has_include("ArduinoJson.h")
+#if ASYNC_JSON_SUPPORT == 1
 static AsyncCallbackJsonWebHandler *handler = new AsyncCallbackJsonWebHandler("/json2");
 #endif
 
 void setup() {
   Serial.begin(115200);
 
-#if SOC_WIFI_SUPPORTED || CONFIG_ESP_WIFI_REMOTE_ENABLED || LT_ARD_HAS_WIFI
+#if ASYNCWEBSERVER_WIFI_SUPPORTED
   WiFi.mode(WIFI_AP);
   WiFi.softAP("esp-captive");
 #endif
 
-#if __has_include("ArduinoJson.h")
+#if ASYNC_JSON_SUPPORT == 1
   //
   // sends JSON using AsyncJsonResponse
   //
@@ -62,8 +56,8 @@ void setup() {
     JsonDocument doc;
     JsonObject root = doc.to<JsonObject>();
     root["foo"] = "bar";
-    serializeJson(root, *response);
-    Serial.println();
+    // serializeJson(root, Serial);
+    // Serial.println();
     request->send(response);
   });
 
@@ -92,12 +86,38 @@ void setup() {
   });
 
   server.addHandler(handler);
+
+  // New Json API since 3.8.2, which works for both Json and MessagePack bodies
+  // curl -v -X POST -H 'Content-Type: application/json' -d '{"name":"You"}' http://192.168.4.1/json3
+
+  server.on("/json3", HTTP_POST, [](AsyncWebServerRequest *request, JsonVariant &json) {
+    Serial.printf("Body request : ");
+    serializeJson(json, Serial);
+    Serial.println();
+    AsyncJsonResponse *response = new AsyncJsonResponse();
+    JsonObject root = response->getRoot().to<JsonObject>();
+    root["hello"] = json.as<JsonObject>()["name"];
+    response->setLength();
+    request->send(response);
+  });
 #endif
 
   server.begin();
 }
 
-// not needed
+static uint32_t lastHeapTime = 0;
+static uint32_t lastHeap = 0;
+
 void loop() {
-  delay(100);
+#ifdef ESP32
+  uint32_t now = millis();
+  if (now - lastHeapTime >= 500) {
+    uint32_t heap = ESP.getFreeHeap();
+    if (heap != lastHeap) {
+      lastHeap = heap;
+      async_ws_log_w("Free heap: %" PRIu32, heap);
+    }
+    lastHeapTime = now;
+  }
+#endif
 }

examples/LargeResponse/LargeResponse.ino

@@ -0,0 +1,178 @@
+// SPDX-License-Identifier: LGPL-3.0-or-later
+// Copyright 2016-2026 Hristo Gochkov, Mathieu Carbou, Emil Muratov, Will Miles
+
+//
+// Example to send a large response and control the filling of the buffer.
+//
+// This is also a MRE for:
+// - https://github.com/ESP32Async/ESPAsyncWebServer/issues/242
+// - https://github.com/ESP32Async/ESPAsyncWebServer/issues/315
+//
+
+#include <Arduino.h>
+#if defined(ESP32) || defined(LIBRETINY)
+#include <AsyncTCP.h>
+#include <WiFi.h>
+#elif defined(ESP8266)
+#include <ESP8266WiFi.h>
+#include <ESPAsyncTCP.h>
+#elif defined(TARGET_RP2040) || defined(TARGET_RP2350) || defined(PICO_RP2040) || defined(PICO_RP2350)
+#include <RPAsyncTCP.h>
+#include <WiFi.h>
+#endif
+
+#include <ESPAsyncWebServer.h>
+
+static AsyncWebServer server(80);
+
+static const size_t totalResponseSize = 16 * 1000;  // 16 KB
+static char fillChar = 'A';
+
+class CustomResponse : public AsyncAbstractResponse {
+public:
+  explicit CustomResponse() {
+    _code = 200;
+    _contentType = "text/plain";
+    _sendContentLength = false;
+  }
+
+  bool _sourceValid() const override {
+    return true;
+  }
+
+  size_t _fillBuffer(uint8_t *buf, size_t buflen) override {
+    if (_sent == RESPONSE_TRY_AGAIN) {
+      Serial.println("Simulating temporary unavailability of data...");
+      _sent = 0;
+      return RESPONSE_TRY_AGAIN;
+    }
+    size_t remaining = totalResponseSize - _sent;
+    if (remaining == 0) {
+      return 0;
+    }
+    if (buflen > remaining) {
+      buflen = remaining;
+    }
+    Serial.printf("Filling '%c' @ sent: %u, buflen: %u\n", fillChar, _sent, buflen);
+    std::fill_n(buf, buflen, static_cast<uint8_t>(fillChar));
+    _sent += buflen;
+    fillChar = (fillChar == 'Z') ? 'A' : fillChar + 1;
+    return buflen;
+  }
+
+private:
+  char fillChar = 'A';
+  size_t _sent = 0;
+};
+
+// Code to reproduce issues:
+// - https://github.com/ESP32Async/ESPAsyncWebServer/issues/242
+// - https://github.com/ESP32Async/ESPAsyncWebServer/issues/315
+//
+// https://github.com/ESP32Async/ESPAsyncWebServer/pull/317#issuecomment-3421141039
+//
+// I cracked it.
+// So this is how it works:
+// That space that _tcp is writing to identified by CONFIG_TCP_SND_BUF_DEFAULT (and is value-matching with default TCP windows size which is very confusing itself).
+// The space returned by client()->write() and client->space() somehow might not be atomically/thread synced (had not dived that deep yet). So if first call to _fillBuffer is done via user-code thread and ended up with some small amount of data consumed and second one is done by _poll or _ack? returns full size again! This is where old code fails.
+// If you change your class this way it will fail 100%.
+class CustomResponseMRE : public AsyncAbstractResponse {
+public:
+  explicit CustomResponseMRE() {
+    _code = 200;
+    _contentType = "text/plain";
+    _sendContentLength = false;
+    // add some useless headers
+    addHeader("Clear-Site-Data", "Clears browsing data (e.g., cookies, storage, cache) associated with the requesting website.");
+    addHeader(
+      "No-Vary-Search", "Specifies a set of rules that define how a URL's query parameters will affect cache matching. These rules dictate whether the same "
+                        "URL with different URL parameters should be saved as separate browser cache entries"
+    );
+  }
+
+  bool _sourceValid() const override {
+    return true;
+  }
+
+  size_t _fillBuffer(uint8_t *buf, size_t buflen) override {
+    if (fillChar == NULL) {
+      fillChar = 'A';
+      return RESPONSE_TRY_AGAIN;
+    }
+    if (_sent == RESPONSE_TRY_AGAIN) {
+      Serial.println("Simulating temporary unavailability of data...");
+      _sent = 0;
+      return RESPONSE_TRY_AGAIN;
+    }
+    size_t remaining = totalResponseSize - _sent;
+    if (remaining == 0) {
+      return 0;
+    }
+    if (buflen > remaining) {
+      buflen = remaining;
+    }
+    Serial.printf("Filling '%c' @ sent: %u, buflen: %u\n", fillChar, _sent, buflen);
+    std::fill_n(buf, buflen, static_cast<uint8_t>(fillChar));
+    _sent += buflen;
+    fillChar = (fillChar == 'Z') ? 'A' : fillChar + 1;
+    return buflen;
+  }
+
+private:
+  char fillChar = NULL;
+  size_t _sent = 0;
+};
+
+void setup() {
+  Serial.begin(115200);
+
+#if ASYNCWEBSERVER_WIFI_SUPPORTED
+  WiFi.mode(WIFI_AP);
+  WiFi.softAP("esp-captive");
+#endif
+
+  // Example to use a AwsResponseFiller
+  //
+  // curl -v http://192.168.4.1/1 | grep -o '.' | sort | uniq -c
+  //
+  // Should output 16000 and a distribution of letters which is the same in ESP32 logs and console
+  //
+  server.on("/1", HTTP_GET, [](AsyncWebServerRequest *request) {
+    fillChar = 'A';
+    AsyncWebServerResponse *response = request->beginResponse("text/plain", totalResponseSize, [](uint8_t *buffer, size_t maxLen, size_t index) -> size_t {
+      size_t remaining = totalResponseSize - index;
+      size_t toSend = (remaining < maxLen) ? remaining : maxLen;
+      Serial.printf("Filling '%c' @ index: %u, maxLen: %u, toSend: %u\n", fillChar, index, maxLen, toSend);
+      std::fill_n(buffer, toSend, static_cast<uint8_t>(fillChar));
+      fillChar = (fillChar == 'Z') ? 'A' : fillChar + 1;
+      return toSend;
+    });
+    request->send(response);
+  });
+
+  // Example to use a AsyncAbstractResponse
+  //
+  // curl -v http://192.168.4.1/2 | grep -o '.' | sort | uniq -c
+  //
+  // Should output 16000 and a distribution of letters which is the same in ESP32 logs and console
+  //
+  server.on("/2", HTTP_GET, [](AsyncWebServerRequest *request) {
+    request->send(new CustomResponse());
+  });
+
+  // Example to use a AsyncAbstractResponse
+  //
+  // curl -v http://192.168.4.1/3 | grep -o '.' | sort | uniq -c
+  //
+  // Should output 16000 and a distribution of letters which is the same in ESP32 logs and console
+  //
+  server.on("/3", HTTP_GET, [](AsyncWebServerRequest *request) {
+    request->send(new CustomResponseMRE());
+  });
+
+  server.begin();
+}
+
+void loop() {
+  delay(100);
+}

examples/Logging/Logging.ino

@@ -1,5 +1,5 @@
 // SPDX-License-Identifier: LGPL-3.0-or-later
-// Copyright 2016-2025 Hristo Gochkov, Mathieu Carbou, Emil Muratov
+// Copyright 2016-2026 Hristo Gochkov, Mathieu Carbou, Emil Muratov, Will Miles
 
 //
 // Show how to log the incoming request and response as a curl-like syntax
@@ -25,7 +25,7 @@ static AsyncLoggingMiddleware requestLogger;
 void setup() {
   Serial.begin(115200);
 
-#if SOC_WIFI_SUPPORTED || CONFIG_ESP_WIFI_REMOTE_ENABLED || LT_ARD_HAS_WIFI
+#if ASYNCWEBSERVER_WIFI_SUPPORTED
   WiFi.mode(WIFI_AP);
   WiFi.softAP("esp-captive");
 #endif

examples/MessagePack/MessagePack.ino

@@ -1,5 +1,5 @@
 // SPDX-License-Identifier: LGPL-3.0-or-later
-// Copyright 2016-2025 Hristo Gochkov, Mathieu Carbou, Emil Muratov
+// Copyright 2016-2026 Hristo Gochkov, Mathieu Carbou, Emil Muratov, Will Miles
 
 //
 // Shows how to send and receive Message Pack data
@@ -19,27 +19,21 @@
 
 #include <ESPAsyncWebServer.h>
 
-#if __has_include("ArduinoJson.h")
-#include <ArduinoJson.h>
-#include <AsyncJson.h>
-#include <AsyncMessagePack.h>
-#endif
-
 static AsyncWebServer server(80);
 
-#if __has_include("ArduinoJson.h")
-static AsyncCallbackMessagePackWebHandler *handler = new AsyncCallbackMessagePackWebHandler("/msgpack2");
+#if ASYNC_JSON_SUPPORT == 1
+static AsyncCallbackJsonWebHandler *handler = new AsyncCallbackJsonWebHandler("/msgpack2");
 #endif
 
 void setup() {
   Serial.begin(115200);
 
-#if SOC_WIFI_SUPPORTED || CONFIG_ESP_WIFI_REMOTE_ENABLED || LT_ARD_HAS_WIFI
+#if ASYNCWEBSERVER_WIFI_SUPPORTED
   WiFi.mode(WIFI_AP);
   WiFi.softAP("esp-captive");
 #endif
 
-#if __has_include("ArduinoJson.h")
+#if ASYNC_JSON_SUPPORT == 1
   //
   // sends MessagePack using AsyncMessagePackResponse
   //
@@ -57,18 +51,26 @@ void setup() {
   //
   // curl -v http://192.168.4.1/msgpack2
   //
+  // Save file: curl -v http://192.168.4.1/msgpack2 -o msgpack.bin
+  //
   server.on("/msgpack2", HTTP_GET, [](AsyncWebServerRequest *request) {
     AsyncResponseStream *response = request->beginResponseStream("application/msgpack");
     JsonDocument doc;
     JsonObject root = doc.to<JsonObject>();
-    root["foo"] = "bar";
+    root["name"] = "Bob";
     serializeMsgPack(root, *response);
     request->send(response);
   });
 
+  // POST file:
+  //
+  // curl -v -X POST -H 'Content-Type: application/msgpack' --data-binary @msgpack.bin http://192.168.4.1/msgpack2
+  //
   handler->setMethod(HTTP_POST | HTTP_PUT);
   handler->onRequest([](AsyncWebServerRequest *request, JsonVariant &json) {
+    Serial.printf("Body request /msgpack2 : ");  // should print: Body request /msgpack2 : {"name":"Bob"}
     serializeJson(json, Serial);
+    Serial.println();
     AsyncMessagePackResponse *response = new AsyncMessagePackResponse();
     JsonObject root = response->getRoot().to<JsonObject>();
     root["hello"] = json.as<JsonObject>()["name"];
@@ -77,6 +79,22 @@ void setup() {
   });
 
   server.addHandler(handler);
+
+  // New Json API since 3.8.2, which works for both Json and MessagePack bodies
+  //
+  // curl -v -X POST -H 'Content-Type: application/json' -d '{"name":"You"}' http://192.168.4.1/msgpack3
+  // curl -v -X POST -H 'Content-Type: application/msgpack' --data-binary @msgpack.bin http://192.168.4.1/msgpack3
+  //
+  server.on("/msgpack3", HTTP_POST, [](AsyncWebServerRequest *request, JsonVariant &json) {
+    Serial.printf("Body request /msgpack3 : ");  // should print: Body request /msgpack3 : {"name":"Bob"}
+    serializeJson(json, Serial);
+    Serial.println();
+    AsyncJsonResponse *response = new AsyncJsonResponse();
+    JsonObject root = response->getRoot().to<JsonObject>();
+    root["hello"] = json.as<JsonObject>()["name"];
+    response->setLength();
+    request->send(response);
+  });
 #endif
 
   server.begin();

examples/Middleware/Middleware.ino

@@ -1,5 +1,5 @@
 // SPDX-License-Identifier: LGPL-3.0-or-later
-// Copyright 2016-2025 Hristo Gochkov, Mathieu Carbou, Emil Muratov
+// Copyright 2016-2026 Hristo Gochkov, Mathieu Carbou, Emil Muratov, Will Miles
 
 //
 // Show how to sue Middleware
@@ -34,7 +34,7 @@ public:
 void setup() {
   Serial.begin(115200);
 
-#if SOC_WIFI_SUPPORTED || CONFIG_ESP_WIFI_REMOTE_ENABLED || LT_ARD_HAS_WIFI
+#if ASYNCWEBSERVER_WIFI_SUPPORTED
   WiFi.mode(WIFI_AP);
   WiFi.softAP("esp-captive");
 #endif

examples/Params/Params.ino

@@ -1,5 +1,5 @@
 // SPDX-License-Identifier: LGPL-3.0-or-later
-// Copyright 2016-2025 Hristo Gochkov, Mathieu Carbou, Emil Muratov
+// Copyright 2016-2026 Hristo Gochkov, Mathieu Carbou, Emil Muratov, Will Miles
 
 //
 // Query parameters and body parameters
@@ -74,7 +74,7 @@ static const size_t htmlContentLength = strlen_P(htmlContent);
 void setup() {
   Serial.begin(115200);
 
-#if SOC_WIFI_SUPPORTED || CONFIG_ESP_WIFI_REMOTE_ENABLED || LT_ARD_HAS_WIFI
+#if ASYNCWEBSERVER_WIFI_SUPPORTED
   WiFi.mode(WIFI_AP);
   WiFi.softAP("esp-captive");
 #endif

examples/PartitionDownloader/PartitionDownloader.ino

@@ -1,5 +1,5 @@
 // SPDX-License-Identifier: LGPL-3.0-or-later
-// Copyright 2016-2025 Hristo Gochkov, Mathieu Carbou, Emil Muratov
+// Copyright 2016-2026 Hristo Gochkov, Mathieu Carbou, Emil Muratov, Will Miles
 
 //
 // - Download ESP32 partition by name and/or type and/or subtype
@@ -34,7 +34,7 @@ static AsyncWebServer server(80);
 void setup() {
   Serial.begin(115200);
 
-#if SOC_WIFI_SUPPORTED || CONFIG_ESP_WIFI_REMOTE_ENABLED || LT_ARD_HAS_WIFI
+#if ASYNCWEBSERVER_WIFI_SUPPORTED
   WiFi.mode(WIFI_AP);
   WiFi.softAP("esp-captive");
 #endif

examples/PerfTests/PerfTests.ino

@@ -1,5 +1,5 @@
 // SPDX-License-Identifier: LGPL-3.0-or-later
-// Copyright 2016-2025 Hristo Gochkov, Mathieu Carbou, Emil Muratov
+// Copyright 2016-2026 Hristo Gochkov, Mathieu Carbou, Emil Muratov, Will Miles
 
 //
 // Perf tests
@@ -91,7 +91,7 @@ static volatile size_t requests = 0;
 void setup() {
   Serial.begin(115200);
 
-#if SOC_WIFI_SUPPORTED || CONFIG_ESP_WIFI_REMOTE_ENABLED || LT_ARD_HAS_WIFI
+#if ASYNCWEBSERVER_WIFI_SUPPORTED
   WiFi.mode(WIFI_AP);
   WiFi.softAP("esp-captive");
 #endif
@@ -118,9 +118,8 @@ void setup() {
 
   // HTTP endpoint
   //
-  // > brew install autocannon
-  // > autocannon -c 10 -w 10 -d 20 http://192.168.4.1
-  // > autocannon -c 16 -w 16 -d 20 http://192.168.4.1
+  // > autocannon -c 16 -w 16 -d 20 --renderStatusCodes  http://192.168.4.1/
+  // > ab -c 16 -t 20 http://192.168.4.1/
   //
   server.on("/", HTTP_GET, [](AsyncWebServerRequest *request) {
     // need to cast to uint8_t*
@@ -142,6 +141,11 @@ void setup() {
   //
   // time curl -N -v -G -d 'd=2000' -d 'l=10000'  http://192.168.4.1/slow.html --output -
   //
+  // THIS CODE WILL CRASH BECAUSE OF THE WATCHDOG.
+  // IF YOU REALLY NEED TO DO THIS, YOU MUST DISABLE THE TWDT
+  //
+  // CORRECT WAY IS TO USE SSE OR WEBSOCKETS TO DO THE COSTLY PROCESSING ASYNC.
+  //
   server.on("/slow.html", HTTP_GET, [](AsyncWebServerRequest *request) {
     requests = requests + 1;
     uint32_t d = request->getParam("d")->value().toInt();
@@ -168,7 +172,6 @@ void setup() {
   // SSS endpoint
   //
   // launch 16 concurrent workers for 30 seconds
-  // > for i in {1..10}; do ( count=$(gtimeout 30 curl -s -N -H "Accept: text/event-stream" http://192.168.4.1/events 2>&1 | grep -c "^data:"); echo "Total: $count events, $(echo "$count / 4" | bc -l) events / second" ) & done;
   // > for i in {1..16}; do ( count=$(gtimeout 30 curl -s -N -H "Accept: text/event-stream" http://192.168.4.1/events 2>&1 | grep -c "^data:"); echo "Total: $count events, $(echo "$count / 4" | bc -l) events / second" ) & done;
   //
   // With AsyncTCP, with 16 workers: a lot of "Event message queue overflow: discard message", no crash

examples/RateLimit/RateLimit.ino

@@ -1,5 +1,5 @@
 // SPDX-License-Identifier: LGPL-3.0-or-later
-// Copyright 2016-2025 Hristo Gochkov, Mathieu Carbou, Emil Muratov
+// Copyright 2016-2026 Hristo Gochkov, Mathieu Carbou, Emil Muratov, Will Miles
 
 //
 // Show how to rate limit the server or some endpoints
@@ -25,7 +25,7 @@ static AsyncRateLimitMiddleware rateLimit;
 void setup() {
   Serial.begin(115200);
 
-#if SOC_WIFI_SUPPORTED || CONFIG_ESP_WIFI_REMOTE_ENABLED || LT_ARD_HAS_WIFI
+#if ASYNCWEBSERVER_WIFI_SUPPORTED
   WiFi.mode(WIFI_AP);
   WiFi.softAP("esp-captive");
 #endif

examples/Redirect/Redirect.ino

@@ -1,5 +1,5 @@
 // SPDX-License-Identifier: LGPL-3.0-or-later
-// Copyright 2016-2025 Hristo Gochkov, Mathieu Carbou, Emil Muratov
+// Copyright 2016-2026 Hristo Gochkov, Mathieu Carbou, Emil Muratov, Will Miles
 
 //
 // Shows how to redirect
@@ -24,7 +24,7 @@ static AsyncWebServer server(80);
 void setup() {
   Serial.begin(115200);
 
-#if SOC_WIFI_SUPPORTED || CONFIG_ESP_WIFI_REMOTE_ENABLED || LT_ARD_HAS_WIFI
+#if ASYNCWEBSERVER_WIFI_SUPPORTED
   WiFi.mode(WIFI_AP);
   WiFi.softAP("esp-captive");
 #endif

examples/RequestContinuation/RequestContinuation.ino

@@ -1,5 +1,5 @@
 // SPDX-License-Identifier: LGPL-3.0-or-later
-// Copyright 2016-2025 Hristo Gochkov, Mathieu Carbou, Emil Muratov
+// Copyright 2016-2026 Hristo Gochkov, Mathieu Carbou, Emil Muratov, Will Miles
 
 //
 // Shows how to use request continuation to pause a request for a long processing task, and be able to resume it later.
@@ -34,7 +34,7 @@ static AsyncWebServerRequestPtr gpioRequest;
 void setup() {
   Serial.begin(115200);
 
-#if SOC_WIFI_SUPPORTED || CONFIG_ESP_WIFI_REMOTE_ENABLED || LT_ARD_HAS_WIFI
+#if ASYNCWEBSERVER_WIFI_SUPPORTED
   WiFi.mode(WIFI_AP);
   WiFi.softAP("esp-captive");
 #endif

examples/RequestContinuationComplete/RequestContinuationComplete.ino

@@ -1,5 +1,5 @@
 // SPDX-License-Identifier: LGPL-3.0-or-later
-// Copyright 2016-2025 Hristo Gochkov, Mathieu Carbou, Emil Muratov
+// Copyright 2016-2026 Hristo Gochkov, Mathieu Carbou, Emil Muratov, Will Miles
 
 //
 // Shows how to use request continuation to pause a request for a long processing task, and be able to resume it later.
@@ -94,7 +94,7 @@ static bool processLongRunningOperation(LongRunningOperation *op) {
 void setup() {
   Serial.begin(115200);
 
-#if SOC_WIFI_SUPPORTED || CONFIG_ESP_WIFI_REMOTE_ENABLED || LT_ARD_HAS_WIFI
+#if ASYNCWEBSERVER_WIFI_SUPPORTED
   WiFi.mode(WIFI_AP);
   WiFi.softAP("esp-captive");
 #endif

examples/ResumableDownload/ResumableDownload.ino

@@ -1,5 +1,5 @@
 // SPDX-License-Identifier: LGPL-3.0-or-later
-// Copyright 2016-2025 Hristo Gochkov, Mathieu Carbou, Emil Muratov
+// Copyright 2016-2026 Hristo Gochkov, Mathieu Carbou, Emil Muratov, Will Miles
 
 //
 // Make sure resumable downloads can be implemented (HEAD request / response and Range header)
@@ -24,7 +24,7 @@ static AsyncWebServer server(80);
 void setup() {
   Serial.begin(115200);
 
-#if SOC_WIFI_SUPPORTED || CONFIG_ESP_WIFI_REMOTE_ENABLED || LT_ARD_HAS_WIFI
+#if ASYNCWEBSERVER_WIFI_SUPPORTED
   WiFi.mode(WIFI_AP);
   WiFi.softAP("esp-captive");
 #endif

examples/Rewrite/Rewrite.ino

@@ -1,5 +1,5 @@
 // SPDX-License-Identifier: LGPL-3.0-or-later
-// Copyright 2016-2025 Hristo Gochkov, Mathieu Carbou, Emil Muratov
+// Copyright 2016-2026 Hristo Gochkov, Mathieu Carbou, Emil Muratov, Will Miles
 
 //
 // Shows how to rewrite URLs
@@ -24,7 +24,7 @@ static AsyncWebServer server(80);
 void setup() {
   Serial.begin(115200);
 
-#if SOC_WIFI_SUPPORTED || CONFIG_ESP_WIFI_REMOTE_ENABLED || LT_ARD_HAS_WIFI
+#if ASYNCWEBSERVER_WIFI_SUPPORTED
   WiFi.mode(WIFI_AP);
   WiFi.softAP("esp-captive");
 #endif

examples/ServerSentEvents/ServerSentEvents.ino

@@ -1,5 +1,5 @@
 // SPDX-License-Identifier: LGPL-3.0-or-later
-// Copyright 2016-2025 Hristo Gochkov, Mathieu Carbou, Emil Muratov
+// Copyright 2016-2026 Hristo Gochkov, Mathieu Carbou, Emil Muratov, Will Miles
 
 //
 // SSE example
@@ -58,7 +58,7 @@ static AsyncEventSource events("/events");
 void setup() {
   Serial.begin(115200);
 
-#if SOC_WIFI_SUPPORTED || CONFIG_ESP_WIFI_REMOTE_ENABLED || LT_ARD_HAS_WIFI
+#if ASYNCWEBSERVER_WIFI_SUPPORTED
   WiFi.mode(WIFI_AP);
   WiFi.softAP("esp-captive");
 #endif
@@ -71,12 +71,12 @@ void setup() {
   });
 
   events.onConnect([](AsyncEventSourceClient *client) {
-    Serial.printf("SSE Client connected! ID: %" PRIu32 "\n", client->lastId());
+    Serial.printf("SSE Client connected!");
     client->send("hello!", NULL, millis(), 1000);
   });
 
   events.onDisconnect([](AsyncEventSourceClient *client) {
-    Serial.printf("SSE Client disconnected! ID: %" PRIu32 "\n", client->lastId());
+    Serial.printf("SSE Client disconnected!");
   });
 
   server.addHandler(&events);

examples/ServerSentEvents_PR156/ServerSentEvents_PR156.ino

@@ -1,5 +1,5 @@
 // SPDX-License-Identifier: LGPL-3.0-or-later
-// Copyright 2016-2025 Hristo Gochkov, Mathieu Carbou, Emil Muratov
+// Copyright 2016-2026 Hristo Gochkov, Mathieu Carbou, Emil Muratov, Will Miles
 
 //
 // SSE example
@@ -64,7 +64,7 @@ static constexpr uint32_t timeoutClose = 15000;
 void setup() {
   Serial.begin(115200);
 
-#if SOC_WIFI_SUPPORTED || CONFIG_ESP_WIFI_REMOTE_ENABLED || LT_ARD_HAS_WIFI
+#if ASYNCWEBSERVER_WIFI_SUPPORTED
   WiFi.mode(WIFI_AP);
   WiFi.softAP("esp-captive");
 #endif

examples/ServerState/ServerState.ino

@@ -1,5 +1,5 @@
 // SPDX-License-Identifier: LGPL-3.0-or-later
-// Copyright 2016-2025 Hristo Gochkov, Mathieu Carbou, Emil Muratov
+// Copyright 2016-2026 Hristo Gochkov, Mathieu Carbou, Emil Muratov, Will Miles
 
 //
 // Server state example
@@ -25,7 +25,7 @@ static AsyncWebServer server2(80);
 void setup() {
   Serial.begin(115200);
 
-#if SOC_WIFI_SUPPORTED || CONFIG_ESP_WIFI_REMOTE_ENABLED || LT_ARD_HAS_WIFI
+#if ASYNCWEBSERVER_WIFI_SUPPORTED
   WiFi.mode(WIFI_AP);
   WiFi.softAP("esp-captive");
 #endif

examples/SkipServerMiddleware/SkipServerMiddleware.ino

@@ -1,5 +1,5 @@
 // SPDX-License-Identifier: LGPL-3.0-or-later
-// Copyright 2016-2025 Hristo Gochkov, Mathieu Carbou, Emil Muratov
+// Copyright 2016-2026 Hristo Gochkov, Mathieu Carbou, Emil Muratov, Will Miles
 
 //
 // Authentication and authorization middlewares
@@ -27,7 +27,7 @@ static AsyncLoggingMiddleware logging;
 void setup() {
   Serial.begin(115200);
 
-#if SOC_WIFI_SUPPORTED || CONFIG_ESP_WIFI_REMOTE_ENABLED || LT_ARD_HAS_WIFI
+#if ASYNCWEBSERVER_WIFI_SUPPORTED
   WiFi.mode(WIFI_AP);
   WiFi.softAP("esp-captive");
 #endif

examples/SlowChunkResponse/SlowChunkResponse.ino

@@ -1,5 +1,5 @@
 // SPDX-License-Identifier: LGPL-3.0-or-later
-// Copyright 2016-2025 Hristo Gochkov, Mathieu Carbou, Emil Muratov
+// Copyright 2016-2026 Hristo Gochkov, Mathieu Carbou, Emil Muratov, Will Miles
 
 //
 // Simulate a slow response in a chunk response (like file download from SD Card)
@@ -89,7 +89,7 @@ static size_t charactersIndex = 0;
 void setup() {
   Serial.begin(115200);
 
-#if SOC_WIFI_SUPPORTED || CONFIG_ESP_WIFI_REMOTE_ENABLED || LT_ARD_HAS_WIFI
+#if ASYNCWEBSERVER_WIFI_SUPPORTED
   WiFi.mode(WIFI_AP);
   WiFi.softAP("esp-captive");
 #endif
@@ -114,6 +114,11 @@ void setup() {
   //
   // time curl -N -v -G -d 'd=2000' -d 'l=10000'  http://192.168.4.1/slow.html --output -
   //
+  // THIS CODE WILL CRASH BECAUSE OF THE WATCHDOG.
+  // IF YOU REALLY NEED TO DO THIS, YOU MUST DISABLE THE TWDT
+  //
+  // CORRECT WAY IS TO USE SSE OR WEBSOCKETS TO DO THE COSTLY PROCESSING ASYNC.
+  //
   server.on("/slow.html", HTTP_GET, [](AsyncWebServerRequest *request) {
     uint32_t d = request->getParam("d")->value().toInt();
     uint32_t l = request->getParam("l")->value().toInt();

examples/StaticFile/StaticFile.ino

@@ -1,5 +1,5 @@
 // SPDX-License-Identifier: LGPL-3.0-or-later
-// Copyright 2016-2025 Hristo Gochkov, Mathieu Carbou, Emil Muratov
+// Copyright 2016-2026 Hristo Gochkov, Mathieu Carbou, Emil Muratov, Will Miles
 
 //
 // Shows how to serve a static file
@@ -111,7 +111,7 @@ static const size_t index2_html_gz_len = sizeof(index2_html_gz);
 void setup() {
   Serial.begin(115200);
 
-#if SOC_WIFI_SUPPORTED || CONFIG_ESP_WIFI_REMOTE_ENABLED || LT_ARD_HAS_WIFI
+#if ASYNCWEBSERVER_WIFI_SUPPORTED
   WiFi.mode(WIFI_AP);
   WiFi.softAP("esp-captive");
 #endif

examples/Templates/Templates.ino

@@ -1,5 +1,5 @@
 // SPDX-License-Identifier: LGPL-3.0-or-later
-// Copyright 2016-2025 Hristo Gochkov, Mathieu Carbou, Emil Muratov
+// Copyright 2016-2026 Hristo Gochkov, Mathieu Carbou, Emil Muratov, Will Miles
 
 //
 // Shows how to serve a static and dynamic template
@@ -33,10 +33,23 @@ static const char *htmlContent PROGMEM = R"(
 
 static const size_t htmlContentLength = strlen_P(htmlContent);
 
+// Variables used for dynamic cacheable template
+static unsigned uptimeInMinutes = 0;
+static AsyncStaticWebHandler *uptimeHandler = nullptr;
+
+// Utility function for performing that update
+static void setUptimeInMinutes(unsigned t) {
+  uptimeInMinutes = t;
+  // Update caching header with a new value as well
+  if (uptimeHandler) {
+    uptimeHandler->setLastModified();
+  }
+}
+
 void setup() {
   Serial.begin(115200);
 
-#if SOC_WIFI_SUPPORTED || CONFIG_ESP_WIFI_REMOTE_ENABLED || LT_ARD_HAS_WIFI
+#if ASYNCWEBSERVER_WIFI_SUPPORTED
   WiFi.mode(WIFI_AP);
   WiFi.softAP("esp-captive");
 #endif
@@ -56,35 +69,68 @@ void setup() {
 
   // Serve the static template file
   //
+  // This call will have caching headers automatically added as it is a static file.
+  //
   // curl -v http://192.168.4.1/template.html
   server.serveStatic("/template.html", LittleFS, "/template.html");
 
-  // Serve the static template with a template processor
+  // Serve a template with dynamic content
   //
-  // ServeStatic static is used to serve static output which never changes over time.
-  // This special endpoints automatically adds caching headers.
-  // If a template processor is used, it must ensure that the outputted content will always be the same over time and never changes.
-  // Otherwise, do not use serveStatic.
-  // Example below: IP never changes.
+  // serveStatic recognizes that template processing is in use, and will not automatically
+  // add caching headers.
   //
-  // curl -v http://192.168.4.1/index.html
-  server.serveStatic("/index.html", LittleFS, "/template.html").setTemplateProcessor([](const String &var) -> String {
+  // curl -v http://192.168.4.1/dynamic.html
+  server.serveStatic("/dynamic.html", LittleFS, "/template.html").setTemplateProcessor([](const String &var) -> String {
     if (var == "USER") {
-      return "Bob";
+      return String("Bob ") + millis();
     }
     return emptyString;
   });
 
-  // Serve a template with dynamic content
+  // Serve a static template with a template processor
   //
-  // to serve a template with dynamic content (output changes over time), use normal
-  // Example below: content changes over tinme do not use serveStatic.
+  // By explicitly calling setLastModified() on the handler object, we enable
+  // sending the caching headers, even when a template is in use.
+  // This pattern should never be used with template data that can change.
+  // Example below: USER never changes.
   //
-  // curl -v http://192.168.4.1/dynamic.html
-  server.on("/dynamic.html", HTTP_GET, [](AsyncWebServerRequest *request) {
-    request->send(LittleFS, "/template.html", "text/html", false, [](const String &var) -> String {
+  // curl -v http://192.168.4.1/index.html
+  server.serveStatic("/index.html", LittleFS, "/template.html")
+    .setTemplateProcessor([](const String &var) -> String {
       if (var == "USER") {
-        return String("Bob ") + millis();
+        return "Bob";
+      }
+      return emptyString;
+    })
+    .setLastModified("Sun, 28 Sep 2025 01:02:03 GMT");
+
+  // Serve a template with dynamic content *and* caching
+  //
+  // The data used in this template is updated in loop().  loop() is then responsible
+  // for calling setLastModified() on the handler object to notify any caches that
+  // the data has changed.
+  //
+  // curl -v http://192.168.4.1/uptime.html
+  uptimeHandler = &server.serveStatic("/uptime.html", LittleFS, "/template.html").setTemplateProcessor([](const String &var) -> String {
+    if (var == "USER") {
+      return String("Bob ") + uptimeInMinutes + " minutes";
+    }
+    return emptyString;
+  });
+
+  // Serve a template with dynamic content based on user request
+  //
+  // In this case, the template is served via a callback request.  Data from the request
+  // is used to generate the template callback.
+  //
+  // curl -v -G -d "USER=Bob" http://192.168.4.1/user_request.html
+  server.on("/user_request.html", HTTP_GET, [](AsyncWebServerRequest *request) {
+    request->send(LittleFS, "/template.html", "text/html", false, [=](const String &var) -> String {
+      if (var == "USER") {
+        const AsyncWebParameter *param = request->getParam("USER");
+        if (param) {
+          return param->value();
+        }
       }
       return emptyString;
     });
@@ -96,4 +142,11 @@ void setup() {
 // not needed
 void loop() {
   delay(100);
+
+  // Compute uptime
+  unsigned currentUptimeInMinutes = millis() / (60 * 1000);
+
+  if (currentUptimeInMinutes != uptimeInMinutes) {
+    setUptimeInMinutes(currentUptimeInMinutes);
+  }
 }

examples/URIMatcher/README.md

@@ -0,0 +1,349 @@
+# AsyncURIMatcher Example
+
+This example demonstrates the comprehensive URI matching capabilities of the ESPAsyncWebServer library using the `AsyncURIMatcher` class.
+
+## Overview
+
+The `AsyncURIMatcher` class provides flexible and powerful URL routing mechanisms that go beyond simple string matching. It supports various matching strategies that can be combined to create sophisticated routing rules.
+
+**Important**: When using plain strings (not `AsyncURIMatcher` objects), the library uses auto-detection (`URIMatchAuto`) which analyzes the URI pattern and applies appropriate matching rules. This is **not** simple exact matching - it combines exact and folder matching by default!
+
+## What's Demonstrated
+
+This example includes two Arduino sketches:
+
+1. **URIMatcher.ino** - Interactive web-based demonstration with a user-friendly homepage
+2. **URIMatcherTest.ino** - Comprehensive test suite with automated shell script testing
+
+Both sketches create a WiFi Access Point (`esp-captive`) for easy testing without network configuration.
+
+## Auto-Detection Behavior
+
+When you pass a plain string or `const char*` to `server.on()`, the `URIMatchAuto` flag is used, which:
+
+1. **Empty URI**: Matches everything
+2. **Ends with `*`**: Becomes prefix match (`URIMatchPrefix`)
+3. **Contains `/*.ext`**: Becomes extension match (`URIMatchExtension`)
+4. **Starts with `^` and ends with `$`**: Becomes regex match (if enabled)
+5. **Everything else**: Becomes **both** exact and folder match (`URIMatchPrefixFolder | URIMatchExact`)
+
+This means traditional string-based routes like `server.on("/path", handler)` will match:
+
+- `/path` (exact match)
+- `/path/` (folder with trailing slash)
+- `/path/anything` (folder match)
+
+But will **NOT** match `/path-suffix` (prefix without folder separator).
+
+## Features Demonstrated
+
+### 1. **Auto-Detection (Traditional Behavior)**
+
+Demonstrates how traditional string-based routing automatically combines exact and folder matching.
+
+**Examples in URIMatcher.ino:**
+
+- `/auto` - Matches both `/auto` exactly AND `/auto/sub` as folder
+- `/wildcard*` - Auto-detects as prefix match (due to trailing `*`)
+- `/auto-images/*.png` - Auto-detects as extension match (due to `/*.ext` pattern)
+
+**Examples in URIMatcherTest.ino:**
+
+- `/exact` - Matches `/exact`, `/exact/`, and `/exact/sub`
+- `/api/users` - Matches exact path and subpaths under `/api/users/`
+- `/*.json` - Matches any `.json` file anywhere
+- `/*.css` - Matches any `.css` file anywhere
+
+### 2. **Exact Matching (Factory Method)**
+
+Using `AsyncURIMatcher::exact()` matches only the exact URL, **NOT** subpaths.
+
+**Key difference from auto-detection:** `AsyncURIMatcher::exact("/path")` matches **only** `/path`, while `server.on("/path", ...)` matches both `/path` and `/path/sub`.
+
+**Examples in URIMatcher.ino:**
+
+- `AsyncURIMatcher::exact("/exact")` - Matches only `/exact`
+
+**Examples in URIMatcherTest.ino:**
+
+- `AsyncURIMatcher::exact("/factory/exact")` - Matches only `/factory/exact`
+- Does NOT match `/factory/exact/sub` (404 response)
+
+### 3. **Prefix Matching**
+
+Using `AsyncURIMatcher::prefix()` matches URLs that start with the specified pattern.
+
+**Examples in URIMatcher.ino:**
+
+- `AsyncURIMatcher::prefix("/service")` - Matches `/service`, `/service-test`, `/service/status`
+
+**Examples in URIMatcherTest.ino:**
+
+- `AsyncURIMatcher::prefix("/factory/prefix")` - Matches `/factory/prefix`, `/factory/prefix-test`, `/factory/prefix/sub`
+- Traditional: `/api/*` - Matches `/api/data`, `/api/v1/posts`
+- Traditional: `/files/*` - Matches `/files/document.pdf`, `/files/images/photo.jpg`
+
+### 4. **Folder/Directory Matching**
+
+Using `AsyncURIMatcher::dir()` matches URLs under a directory (automatically adds trailing slash).
+
+**Important:** Directory matching requires a trailing slash in the URL - it does NOT match the directory itself.
+
+**Examples in URIMatcher.ino:**
+
+- `AsyncURIMatcher::dir("/admin")` - Matches `/admin/users`, `/admin/settings`
+- Does NOT match `/admin` without trailing slash
+
+**Examples in URIMatcherTest.ino:**
+
+- `AsyncURIMatcher::dir("/factory/dir")` - Matches `/factory/dir/users`, `/factory/dir/sub/path`
+- Does NOT match `/factory/dir` itself (404 response)
+
+### 5. **Extension Matching**
+
+Using `AsyncURIMatcher::ext()` matches files with specific extensions.
+
+**Examples in URIMatcher.ino:**
+
+- `AsyncURIMatcher::ext("/images/*.jpg")` - Matches `/images/photo.jpg`, `/images/sub/pic.jpg`
+
+**Examples in URIMatcherTest.ino:**
+
+- `AsyncURIMatcher::ext("/factory/files/*.txt")` - Matches `/factory/files/doc.txt`, `/factory/files/sub/readme.txt`
+- Does NOT match `/factory/files/doc.pdf` (wrong extension)
+
+### 6. **Case Insensitive Matching**
+
+Using `AsyncURIMatcher::CaseInsensitive` flag matches URLs regardless of character case.
+
+**Examples in URIMatcher.ino:**
+
+- `AsyncURIMatcher::exact("/case", AsyncURIMatcher::CaseInsensitive)` - Matches `/case`, `/CASE`, `/CaSe`
+
+**Examples in URIMatcherTest.ino:**
+
+- Case insensitive exact: `/case/exact`, `/CASE/EXACT`, `/Case/Exact` all work
+- Case insensitive prefix: `/case/prefix`, `/CASE/PREFIX-test`, `/Case/Prefix/sub` all work
+- Case insensitive directory: `/case/dir/users`, `/CASE/DIR/admin`, `/Case/Dir/settings` all work
+- Case insensitive extension: `/case/files/doc.pdf`, `/CASE/FILES/DOC.PDF`, `/Case/Files/Doc.Pdf` all work
+
+### 7. **Regular Expression Matching**
+
+Using `AsyncURIMatcher::regex()` for advanced pattern matching (requires `ASYNCWEBSERVER_REGEX`).
+
+**Examples in URIMatcher.ino:**
+
+```cpp
+#ifdef ASYNCWEBSERVER_REGEX
+AsyncURIMatcher::regex("^/user/([0-9]+)$")  // Matches /user/123, captures ID
+#endif
+```
+
+**Examples in URIMatcherTest.ino:**
+
+- Traditional regex: `^/user/([0-9]+)$` - Matches `/user/123`, `/user/456`
+- Traditional regex: `^/blog/([0-9]{4})/([0-9]{2})/([0-9]{2})$` - Matches `/blog/2023/10/15`
+- Factory regex: `AsyncURIMatcher::regex("^/factory/user/([0-9]+)$")` - Matches `/factory/user/123`
+- Factory regex with multiple captures: `^/factory/blog/([0-9]{4})/([0-9]{2})/([0-9]{2})$`
+- Case insensitive regex: `AsyncURIMatcher::regex("^/factory/search/(.+)$", AsyncURIMatcher::CaseInsensitive)`
+
+### 8. **Combined Flags**
+
+Multiple matching strategies can be combined using the `|` operator.
+
+**Examples in URIMatcher.ino:**
+
+- `AsyncURIMatcher::prefix("/MixedCase", AsyncURIMatcher::CaseInsensitive)` - Prefix match that's case insensitive
+
+### 9. **Special Matchers**
+
+**Examples in URIMatcherTest.ino:**
+
+- `AsyncURIMatcher::all()` - Matches all requests (used with POST method as catch-all)
+
+## Usage Patterns
+
+### Traditional String-based Routing (Auto-Detection)
+
+```cpp
+// Auto-detection with exact + folder matching
+server.on("/api", handler);          // Matches /api AND /api/anything
+server.on("/login", handler);        // Matches /login AND /login/sub
+
+// Auto-detection with prefix matching
+server.on("/prefix*", handler);      // Matches /prefix, /prefix-test, /prefix/sub
+
+// Auto-detection with extension matching
+server.on("/images/*.jpg", handler); // Matches /images/pic.jpg, /images/sub/pic.jpg
+```
+
+### Explicit AsyncURIMatcher Syntax
+
+### Explicit AsyncURIMatcher Syntax
+
+```cpp
+// Exact matching only
+server.on(AsyncURIMatcher("/path", URIMatchExact), handler);
+
+// Prefix matching only
+server.on(AsyncURIMatcher("/api", URIMatchPrefix), handler);
+
+// Combined flags
+server.on(AsyncURIMatcher("/api", URIMatchPrefix | URIMatchCaseInsensitive), handler);
+```
+
+### Factory Functions
+
+```cpp
+// More readable and expressive
+server.on(AsyncURIMatcher::exact("/login"), handler);
+server.on(AsyncURIMatcher::prefix("/api"), handler);
+server.on(AsyncURIMatcher::dir("/admin"), handler);
+server.on(AsyncURIMatcher::ext("/images/*.jpg"), handler);
+
+#ifdef ASYNCWEBSERVER_REGEX
+server.on(AsyncURIMatcher::regex("^/user/([0-9]+)$"), handler);
+#endif
+```
+
+## Available Flags
+
+| Flag                      | Description                                                 |
+| ------------------------- | ----------------------------------------------------------- |
+| `URIMatchAuto`            | Auto-detect match type from pattern (default)               |
+| `URIMatchExact`           | Exact URL match                                             |
+| `URIMatchPrefix`          | Prefix match                                                |
+| `URIMatchPrefixFolder`    | Folder prefix match (requires trailing /)                   |
+| `URIMatchExtension`       | File extension match pattern                                |
+| `URIMatchCaseInsensitive` | Case insensitive matching                                   |
+| `URIMatchRegex`           | Regular expression matching (requires ASYNCWEBSERVER_REGEX) |
+
+## Testing the Example
+
+1. **Upload the sketch** to your ESP32/ESP8266
+2. **Connect to WiFi AP**: `esp-captive` (no password required)
+3. **Navigate to**: `http://192.168.4.1/`
+4. **Explore the examples** by clicking the organized test links
+5. **Monitor Serial output**: Open Serial Monitor to see detailed debugging information for each matched route
+
+### Test URLs Available (All Clickable from Homepage)
+
+**Auto-Detection Examples:**
+
+- `http://192.168.4.1/auto` (exact + folder match)
+- `http://192.168.4.1/auto/sub` (folder match - same handler!)
+- `http://192.168.4.1/wildcard-test` (auto-detected prefix)
+- `http://192.168.4.1/auto-images/photo.png` (auto-detected extension)
+
+**Factory Method Examples:**
+
+- `http://192.168.4.1/exact` (AsyncURIMatcher::exact)
+- `http://192.168.4.1/service/status` (AsyncURIMatcher::prefix)
+- `http://192.168.4.1/admin/users` (AsyncURIMatcher::dir)
+- `http://192.168.4.1/images/photo.jpg` (AsyncURIMatcher::ext)
+
+**Case Insensitive Examples:**
+
+- `http://192.168.4.1/case` (lowercase)
+- `http://192.168.4.1/CASE` (uppercase)
+- `http://192.168.4.1/CaSe` (mixed case)
+
+**Regex Examples (if ASYNCWEBSERVER_REGEX enabled):**
+
+- `http://192.168.4.1/user/123` (captures numeric ID)
+- `http://192.168.4.1/user/456` (captures numeric ID)
+
+**Combined Flags Examples:**
+
+- `http://192.168.4.1/mixedcase-test` (prefix + case insensitive)
+- `http://192.168.4.1/MIXEDCASE/sub` (prefix + case insensitive)
+
+### Console Output
+
+Each handler provides detailed debugging information via Serial output:
+
+```
+Auto-Detection Match (Traditional)
+Matched URL: /auto
+Uses auto-detection: exact + folder matching
+```
+
+```
+Factory Exact Match
+Matched URL: /exact
+Uses AsyncURIMatcher::exact() factory function
+```
+
+```
+Regex Match - User ID
+Matched URL: /user/123
+Captured User ID: 123
+This regex matches /user/{number} pattern
+```
+
+## Compilation Options
+
+### Enable Regex Support
+
+To enable regular expression matching, compile with:
+
+```
+-D ASYNCWEBSERVER_REGEX
+```
+
+In PlatformIO, add to `platformio.ini`:
+
+```ini
+build_flags = -D ASYNCWEBSERVER_REGEX
+```
+
+In Arduino IDE, add to your sketch:
+
+```cpp
+#define ASYNCWEBSERVER_REGEX
+```
+
+## Performance Considerations
+
+1. **Exact matches** are fastest
+2. **Prefix matches** are very efficient
+3. **Regex matches** are slower but most flexible
+4. **Case insensitive** matching adds minimal overhead
+5. **Auto-detection** adds slight parsing overhead at construction time
+
+## Real-World Applications
+
+### REST API Design
+
+```cpp
+// API versioning
+server.on(AsyncURIMatcher::prefix("/api/v1"), handleAPIv1);
+server.on(AsyncURIMatcher::prefix("/api/v2"), handleAPIv2);
+
+// Resource endpoints with IDs
+server.on(AsyncURIMatcher::regex("^/api/users/([0-9]+)$"), handleUserById);
+server.on(AsyncURIMatcher::regex("^/api/posts/([0-9]+)/comments$"), handlePostComments);
+```
+
+### File Serving
+
+```cpp
+// Serve different file types
+server.on(AsyncURIMatcher::ext("/assets/*.css"), serveCSSFiles);
+server.on(AsyncURIMatcher::ext("/assets/*.js"), serveJSFiles);
+server.on(AsyncURIMatcher::ext("/images/*.jpg"), serveImageFiles);
+```
+
+### Admin Interface
+
+```cpp
+// Admin section with authentication
+server.on(AsyncURIMatcher::dir("/admin"), handleAdminPages);
+server.on(AsyncURIMatcher::exact("/admin"), redirectToAdminDashboard);
+```
+
+## See Also
+
+- [ESPAsyncWebServer Documentation](https://github.com/ESP32Async/ESPAsyncWebServer)
+- [Regular Expression Reference](https://en.cppreference.com/w/cpp/regex)
+- Other examples in the `examples/` directory

examples/URIMatcher/URIMatcher.ino

@@ -0,0 +1,276 @@
+// SPDX-License-Identifier: LGPL-3.0-or-later
+// Copyright 2016-2026 Hristo Gochkov, Mathieu Carbou, Emil Muratov, Will Miles
+
+//
+// AsyncURIMatcher Examples - Advanced URI Matching and Routing
+//
+// This example demonstrates the various ways to use AsyncURIMatcher class
+// for flexible URL routing with different matching strategies:
+//
+// 1. Exact matching
+// 2. Prefix matching
+// 3. Folder/directory matching
+// 4. Extension matching
+// 5. Case insensitive matching
+// 6. Regex matching (if ASYNCWEBSERVER_REGEX is enabled)
+// 7. Factory functions for common patterns
+//
+// Test URLs:
+// - Exact: http://192.168.4.1/exact
+// - Prefix: http://192.168.4.1/prefix-anything
+// - Folder: http://192.168.4.1/api/users, http://192.168.4.1/api/posts
+// - Extension: http://192.168.4.1/images/photo.jpg, http://192.168.4.1/docs/readme.pdf
+// - Case insensitive: http://192.168.4.1/CaSe or http://192.168.4.1/case
+// - Wildcard: http://192.168.4.1/wildcard-test
+
+#include <Arduino.h>
+#if defined(ESP32) || defined(LIBRETINY)
+#include <AsyncTCP.h>
+#include <WiFi.h>
+#elif defined(ESP8266)
+#include <ESP8266WiFi.h>
+#include <ESPAsyncTCP.h>
+#elif defined(TARGET_RP2040) || defined(TARGET_RP2350) || defined(PICO_RP2040) || defined(PICO_RP2350)
+#include <RPAsyncTCP.h>
+#include <WiFi.h>
+#endif
+
+#include <ESPAsyncWebServer.h>
+
+static AsyncWebServer server(80);
+
+void setup() {
+  Serial.begin(115200);
+  Serial.println();
+  Serial.println("=== AsyncURIMatcher Example ===");
+
+#if ASYNCWEBSERVER_WIFI_SUPPORTED
+  WiFi.mode(WIFI_AP);
+  WiFi.softAP("esp-captive");
+  Serial.print("AP IP address: ");
+  Serial.println(WiFi.softAPIP());
+#endif
+
+  // =============================================================================
+  // 1. AUTO-DETECTION BEHAVIOR - traditional string-based routing
+  // =============================================================================
+
+  // Traditional string-based routing with auto-detection
+  // This uses URIMatchAuto which combines URIMatchPrefixFolder | URIMatchExact
+  // It will match BOTH "/auto" exactly AND "/auto/" + anything
+  server.on("/auto", HTTP_GET, [](AsyncWebServerRequest *request) {
+    Serial.println("Auto-Detection Match (Traditional)");
+    Serial.println("Matched URL: " + request->url());
+    Serial.println("Uses auto-detection: exact + folder matching");
+    request->send(200, "text/plain", "OK - Auto-detection match");
+  });
+
+  // Auto-detection for wildcard patterns (ends with *)
+  // This auto-detects as URIMatchPrefix
+  server.on("/wildcard*", HTTP_GET, [](AsyncWebServerRequest *request) {
+    Serial.println("Auto-Detected Wildcard (Prefix)");
+    Serial.println("Matched URL: " + request->url());
+    Serial.println("Auto-detected as prefix match due to trailing *");
+    request->send(200, "text/plain", "OK - Wildcard prefix match");
+  });
+
+  // Auto-detection for extension patterns (contains /*.ext)
+  // This auto-detects as URIMatchExtension
+  server.on("/auto-images/*.png", HTTP_GET, [](AsyncWebServerRequest *request) {
+    Serial.println("Auto-Detected Extension Pattern");
+    Serial.println("Matched URL: " + request->url());
+    Serial.println("Auto-detected as extension match due to /*.png pattern");
+    request->send(200, "text/plain", "OK - Extension match");
+  });
+
+  // =============================================================================
+  // 2. EXACT MATCHING - matches only the exact URL (explicit)
+  // =============================================================================
+
+  // Using factory function for exact match
+  server.on(AsyncURIMatcher::exact("/exact"), HTTP_GET, [](AsyncWebServerRequest *request) {
+    Serial.println("Factory Exact Match");
+    Serial.println("Matched URL: " + request->url());
+    Serial.println("Uses AsyncURIMatcher::exact() factory function");
+    request->send(200, "text/plain", "OK - Factory exact match");
+  });
+
+  // =============================================================================
+  // 3. PREFIX MATCHING - matches URLs that start with the pattern
+  // =============================================================================
+
+  // Using factory function for prefix match
+  server.on(AsyncURIMatcher::prefix("/service"), HTTP_GET, [](AsyncWebServerRequest *request) {
+    Serial.println("Service Prefix Match (Factory)");
+    Serial.println("Matched URL: " + request->url());
+    Serial.println("Uses AsyncURIMatcher::prefix() factory function");
+    request->send(200, "text/plain", "OK - Factory prefix match");
+  });
+
+  // =============================================================================
+  // 4. FOLDER/DIRECTORY MATCHING - matches URLs in a folder structure
+  // =============================================================================
+
+  // Folder match using factory function (automatically adds trailing slash)
+  server.on(AsyncURIMatcher::dir("/admin"), HTTP_GET, [](AsyncWebServerRequest *request) {
+    Serial.println("Admin Directory Match");
+    Serial.println("Matched URL: " + request->url());
+    Serial.println("This matches URLs under /admin/ directory");
+    Serial.println("Note: /admin (without slash) will NOT match");
+    request->send(200, "text/plain", "OK - Directory match");
+  });
+
+  // =============================================================================
+  // 5. EXTENSION MATCHING - matches files with specific extensions
+  // =============================================================================
+
+  // Image extension matching
+  server.on(AsyncURIMatcher::ext("/images/*.jpg"), HTTP_GET, [](AsyncWebServerRequest *request) {
+    Serial.println("JPG Image Handler");
+    Serial.println("Matched URL: " + request->url());
+    Serial.println("This matches any .jpg file under /images/");
+    request->send(200, "text/plain", "OK - Extension match");
+  });
+
+  // =============================================================================
+  // 6. CASE INSENSITIVE MATCHING
+  // =============================================================================
+
+  // Case insensitive exact match
+  server.on(AsyncURIMatcher::exact("/case", AsyncURIMatcher::CaseInsensitive), HTTP_GET, [](AsyncWebServerRequest *request) {
+    Serial.println("Case Insensitive Match");
+    Serial.println("Matched URL: " + request->url());
+    Serial.println("This matches /case in any case combination");
+    request->send(200, "text/plain", "OK - Case insensitive match");
+  });
+
+#ifdef ASYNCWEBSERVER_REGEX
+  // =============================================================================
+  // 7. REGEX MATCHING (only available if ASYNCWEBSERVER_REGEX is enabled)
+  // =============================================================================
+
+  // Regex match for numeric IDs
+  server.on(AsyncURIMatcher::regex("^/user/([0-9]+)$"), HTTP_GET, [](AsyncWebServerRequest *request) {
+    Serial.println("Regex Match - User ID");
+    Serial.println("Matched URL: " + request->url());
+    if (request->pathArg(0).length() > 0) {
+      Serial.println("Captured User ID: " + request->pathArg(0));
+    }
+    Serial.println("This regex matches /user/{number} pattern");
+    request->send(200, "text/plain", "OK - Regex match");
+  });
+#endif
+
+  // =============================================================================
+  // 8. COMBINED FLAGS EXAMPLE
+  // =============================================================================
+
+  // Combine multiple flags
+  server.on(AsyncURIMatcher::prefix("/MixedCase", AsyncURIMatcher::CaseInsensitive), HTTP_GET, [](AsyncWebServerRequest *request) {
+    Serial.println("Combined Flags Example");
+    Serial.println("Matched URL: " + request->url());
+    Serial.println("Uses both AsyncURIMatcher::Prefix and AsyncURIMatcher::CaseInsensitive");
+    request->send(200, "text/plain", "OK - Combined flags match");
+  });
+
+  // =============================================================================
+  // 9. HOMEPAGE WITH NAVIGATION
+  // =============================================================================
+
+  server.on("/", HTTP_GET, [](AsyncWebServerRequest *request) {
+    Serial.println("Homepage accessed");
+    String response = R"(<!DOCTYPE html>
+<html>
+<head>
+  <title>AsyncURIMatcher Examples</title>
+  <style>
+    body { font-family: Arial, sans-serif; margin: 20px; }
+    h1 { color: #2E86AB; }
+    .test-link { display: block; margin: 5px 0; padding: 8px; background: #f0f0f0; text-decoration: none; color: #333; border-radius: 4px; }
+    .test-link:hover { background: #e0e0e0; }
+    .section { margin: 20px 0; }
+  </style>
+</head>
+<body>
+  <h1>AsyncURIMatcher Examples</h1>
+
+  <div class="section">
+    <h3>Auto-Detection (Traditional String Matching)</h3>
+    <a href="/auto" class="test-link">/auto (auto-detection: exact + folder)</a>
+    <a href="/auto/sub" class="test-link">/auto/sub (folder match)</a>
+    <a href="/wildcard-test" class="test-link">/wildcard-test (auto prefix)</a>
+    <a href="/auto-images/photo.png" class="test-link">/auto-images/photo.png (auto extension)</a>
+  </div>
+
+  <div class="section">
+    <h3>Factory Method Examples</h3>
+    <a href="/exact" class="test-link">/exact (factory exact)</a>
+    <a href="/service/status" class="test-link">/service/status (factory prefix)</a>
+    <a href="/admin/users" class="test-link">/admin/users (factory directory)</a>
+    <a href="/images/photo.jpg" class="test-link">/images/photo.jpg (factory extension)</a>
+  </div>
+
+  <div class="section">
+    <h3>Case Insensitive Matching</h3>
+    <a href="/case" class="test-link">/case (lowercase)</a>
+    <a href="/CASE" class="test-link">/CASE (uppercase)</a>
+    <a href="/CaSe" class="test-link">/CaSe (mixed case)</a>
+  </div>
+
+)";
+#ifdef ASYNCWEBSERVER_REGEX
+    response += R"(  <div class="section">
+    <h3>Regex Matching</h3>
+    <a href="/user/123" class="test-link">/user/123 (regex numeric ID)</a>
+    <a href="/user/456" class="test-link">/user/456 (regex numeric ID)</a>
+  </div>
+
+)";
+#endif
+    response += R"(  <div class="section">
+    <h3>Combined Flags</h3>
+    <a href="/mixedcase-test" class="test-link">/mixedcase-test (prefix + case insensitive)</a>
+    <a href="/MIXEDCASE/sub" class="test-link">/MIXEDCASE/sub (prefix + case insensitive)</a>
+  </div>
+
+</body>
+</html>)";
+    request->send(200, "text/html", response);
+  });
+
+  // =============================================================================
+  // 10. NOT FOUND HANDLER
+  // =============================================================================
+
+  server.onNotFound([](AsyncWebServerRequest *request) {
+    String html = "<h1>404 - Not Found</h1>";
+    html += "<p>The requested URL <strong>" + request->url() + "</strong> was not found.</p>";
+    html += "<p><a href='/'>← Back to Examples</a></p>";
+    request->send(404, "text/html", html);
+  });
+
+  server.begin();
+
+  Serial.println();
+  Serial.println("=== Server Started ===");
+  Serial.println("Open your browser and navigate to:");
+  Serial.println("http://192.168.4.1/ - Main examples page");
+  Serial.println();
+  Serial.println("Available test endpoints:");
+  Serial.println("• Auto-detection: /auto (exact+folder), /wildcard*, /auto-images/*.png");
+  Serial.println("• Exact matches: /exact");
+  Serial.println("• Prefix matches: /service*");
+  Serial.println("• Folder matches: /admin/*");
+  Serial.println("• Extension matches: /images/*.jpg");
+  Serial.println("• Case insensitive: /case (try /CASE, /Case)");
+#ifdef ASYNCWEBSERVER_REGEX
+  Serial.println("• Regex matches: /user/123");
+#endif
+  Serial.println("• Combined flags: /mixedcase*");
+  Serial.println();
+}
+
+void loop() {
+  // Nothing to do here - the server handles everything asynchronously
+  delay(1000);
+}

examples/URIMatcherTest/URIMatcherTest.ino

@@ -0,0 +1,165 @@
+// SPDX-License-Identifier: LGPL-3.0-or-later
+// Copyright 2016-2026 Hristo Gochkov, Mathieu Carbou, Emil Muratov, Will Miles
+
+//
+// Test for ESPAsyncWebServer URI matching
+//
+// Usage: upload, connect to the AP and run test_routes.sh
+//
+
+#include <Arduino.h>
+#if defined(ESP32) || defined(LIBRETINY)
+#include <AsyncTCP.h>
+#include <WiFi.h>
+#elif defined(ESP8266)
+#include <ESP8266WiFi.h>
+#include <ESPAsyncTCP.h>
+#elif defined(TARGET_RP2040) || defined(TARGET_RP2350) || defined(PICO_RP2040) || defined(PICO_RP2350)
+#include <RPAsyncTCP.h>
+#include <WiFi.h>
+#endif
+
+#include <ESPAsyncWebServer.h>
+
+AsyncWebServer server(80);
+
+void setup() {
+  Serial.begin(115200);
+
+#if ASYNCWEBSERVER_WIFI_SUPPORTED
+  WiFi.mode(WIFI_AP);
+  WiFi.softAP("esp-captive");
+#endif
+
+  // Status endpoint
+  server.on("/status", HTTP_GET, [](AsyncWebServerRequest *request) {
+    request->send(200, "text/plain", "OK");
+  });
+
+  // Exact paths, plus the subpath (/exact matches /exact/sub but not /exact-no-match)
+  server.on("/exact", HTTP_GET, [](AsyncWebServerRequest *request) {
+    request->send(200, "text/plain", "OK");
+  });
+
+  server.on("/api/users", HTTP_GET, [](AsyncWebServerRequest *request) {
+    request->send(200, "text/plain", "OK");
+  });
+
+  // Prefix matching
+  server.on("/api/*", HTTP_GET, [](AsyncWebServerRequest *request) {
+    request->send(200, "text/plain", "OK");
+  });
+
+  server.on("/files/*", HTTP_GET, [](AsyncWebServerRequest *request) {
+    request->send(200, "text/plain", "OK");
+  });
+
+  // Extensions
+  server.on("/*.json", HTTP_GET, [](AsyncWebServerRequest *request) {
+    request->send(200, "application/json", "{\"status\":\"OK\"}");
+  });
+
+  server.on("/*.css", HTTP_GET, [](AsyncWebServerRequest *request) {
+    request->send(200, "text/css", "/* OK */");
+  });
+
+  // =============================================================================
+  // NEW ASYNCURIMATCHER FACTORY METHODS TESTS
+  // =============================================================================
+
+  // Exact match using factory method (does NOT match subpaths like traditional)
+  server.on(AsyncURIMatcher::exact("/factory/exact"), HTTP_GET, [](AsyncWebServerRequest *request) {
+    request->send(200, "text/plain", "OK");
+  });
+
+  // Prefix match using factory method
+  server.on(AsyncURIMatcher::prefix("/factory/prefix"), HTTP_GET, [](AsyncWebServerRequest *request) {
+    request->send(200, "text/plain", "OK");
+  });
+
+  // Directory match using factory method (matches /dir/anything but not /dir itself)
+  server.on(AsyncURIMatcher::dir("/factory/dir"), HTTP_GET, [](AsyncWebServerRequest *request) {
+    request->send(200, "text/plain", "OK");
+  });
+
+  // Extension match using factory method
+  server.on(AsyncURIMatcher::ext("/factory/files/*.txt"), HTTP_GET, [](AsyncWebServerRequest *request) {
+    request->send(200, "text/plain", "OK");
+  });
+
+  // =============================================================================
+  // CASE INSENSITIVE MATCHING TESTS
+  // =============================================================================
+
+  // Case insensitive exact match
+  server.on(AsyncURIMatcher::exact("/case/exact", AsyncURIMatcher::CaseInsensitive), HTTP_GET, [](AsyncWebServerRequest *request) {
+    request->send(200, "text/plain", "OK");
+  });
+
+  // Case insensitive prefix match
+  server.on(AsyncURIMatcher::prefix("/case/prefix", AsyncURIMatcher::CaseInsensitive), HTTP_GET, [](AsyncWebServerRequest *request) {
+    request->send(200, "text/plain", "OK");
+  });
+
+  // Case insensitive directory match
+  server.on(AsyncURIMatcher::dir("/case/dir", AsyncURIMatcher::CaseInsensitive), HTTP_GET, [](AsyncWebServerRequest *request) {
+    request->send(200, "text/plain", "OK");
+  });
+
+  // Case insensitive extension match
+  server.on(AsyncURIMatcher::ext("/case/files/*.PDF", AsyncURIMatcher::CaseInsensitive), HTTP_GET, [](AsyncWebServerRequest *request) {
+    request->send(200, "text/plain", "OK");
+  });
+
+#ifdef ASYNCWEBSERVER_REGEX
+  // Traditional regex patterns (backward compatibility)
+  server.on("^/user/([0-9]+)$", HTTP_GET, [](AsyncWebServerRequest *request) {
+    request->send(200, "text/plain", "OK");
+  });
+
+  server.on("^/blog/([0-9]{4})/([0-9]{2})/([0-9]{2})$", HTTP_GET, [](AsyncWebServerRequest *request) {
+    request->send(200, "text/plain", "OK");
+  });
+
+  // =============================================================================
+  // NEW ASYNCURIMATCHER REGEX FACTORY METHODS
+  // =============================================================================
+
+  // Regex match using factory method
+  server.on(AsyncURIMatcher::regex("^/factory/user/([0-9]+)$"), HTTP_GET, [](AsyncWebServerRequest *request) {
+    request->send(200, "text/plain", "OK");
+  });
+
+  // Case insensitive regex match using factory method
+  server.on(AsyncURIMatcher::regex("^/factory/search/(.+)$", AsyncURIMatcher::CaseInsensitive), HTTP_GET, [](AsyncWebServerRequest *request) {
+    request->send(200, "text/plain", "OK");
+  });
+
+  // Complex regex with multiple capture groups
+  server.on(AsyncURIMatcher::regex("^/factory/blog/([0-9]{4})/([0-9]{2})/([0-9]{2})$"), HTTP_GET, [](AsyncWebServerRequest *request) {
+    request->send(200, "text/plain", "OK");
+  });
+#endif
+
+  // =============================================================================
+  // SPECIAL MATCHERS
+  // =============================================================================
+
+  // Match all POST requests (catch-all before 404)
+  server.on(AsyncURIMatcher::all(), HTTP_POST, [](AsyncWebServerRequest *request) {
+    request->send(200, "text/plain", "OK");
+  });
+
+  // 404 handler
+  server.onNotFound([](AsyncWebServerRequest *request) {
+    request->send(404, "text/plain", "Not Found");
+  });
+
+  server.begin();
+  Serial.println("Server ready");
+}
+
+// not needed
+void loop() {
+  delay(100);
+}

examples/URIMatcherTest/test_routes.sh

@@ -0,0 +1,174 @@
+#!/bin/bash
+
+# URI Matcher Test Script
+# Tests all routes defined in URIMatcherTest.ino
+
+SERVER_IP="${1:-192.168.4.1}"
+SERVER_PORT="80"
+BASE_URL="http://${SERVER_IP}:${SERVER_PORT}"
+
+echo "Testing URI Matcher at $BASE_URL"
+echo "=================================="
+
+# Function to test a route
+test_route() {
+    local path="$1"
+    local expected_status="$2"
+    local description="$3"
+
+    echo -n "Testing $path ... "
+
+    response=$(curl -s -w "HTTPSTATUS:%{http_code}" "$BASE_URL$path" 2>/dev/null)
+    status_code=$(echo "$response" | grep -o "HTTPSTATUS:[0-9]*" | cut -d: -f2)
+
+    if [ "$status_code" = "$expected_status" ]; then
+        echo "✅ PASS ($status_code)"
+    else
+        echo "❌ FAIL (expected $expected_status, got $status_code)"
+        return 1
+    fi
+    return 0
+}
+
+# Test counter
+PASS=0
+FAIL=0
+
+# Test all routes that should return 200 OK
+echo "Testing routes that should work (200 OK):"
+
+if test_route "/status" "200" "Status endpoint"; then ((PASS++)); else ((FAIL++)); fi
+if test_route "/exact" "200" "Exact path"; then ((PASS++)); else ((FAIL++)); fi
+if test_route "/exact/" "200" "Exact path ending with /"; then ((PASS++)); else ((FAIL++)); fi
+if test_route "/exact/sub" "200" "Exact path with subpath /"; then ((PASS++)); else ((FAIL++)); fi
+if test_route "/api/users" "200" "Exact API path"; then ((PASS++)); else ((FAIL++)); fi
+if test_route "/api/data" "200" "API prefix match"; then ((PASS++)); else ((FAIL++)); fi
+if test_route "/api/v1/posts" "200" "API prefix deep"; then ((PASS++)); else ((FAIL++)); fi
+if test_route "/files/document.pdf" "200" "Files prefix"; then ((PASS++)); else ((FAIL++)); fi
+if test_route "/files/images/photo.jpg" "200" "Files prefix deep"; then ((PASS++)); else ((FAIL++)); fi
+if test_route "/config.json" "200" "JSON extension"; then ((PASS++)); else ((FAIL++)); fi
+if test_route "/data/settings.json" "200" "JSON extension in subfolder"; then ((PASS++)); else ((FAIL++)); fi
+if test_route "/style.css" "200" "CSS extension"; then ((PASS++)); else ((FAIL++)); fi
+if test_route "/assets/main.css" "200" "CSS extension in subfolder"; then ((PASS++)); else ((FAIL++)); fi
+
+echo ""
+echo "Testing AsyncURIMatcher factory methods:"
+
+# Factory exact match (should NOT match subpaths)
+if test_route "/factory/exact" "200" "Factory exact match"; then ((PASS++)); else ((FAIL++)); fi
+
+# Factory prefix match
+if test_route "/factory/prefix" "200" "Factory prefix base"; then ((PASS++)); else ((FAIL++)); fi
+if test_route "/factory/prefix-test" "200" "Factory prefix extended"; then ((PASS++)); else ((FAIL++)); fi
+if test_route "/factory/prefix/sub" "200" "Factory prefix subpath"; then ((PASS++)); else ((FAIL++)); fi
+
+# Factory directory match (should NOT match the directory itself)
+if test_route "/factory/dir/users" "200" "Factory directory match"; then ((PASS++)); else ((FAIL++)); fi
+if test_route "/factory/dir/sub/path" "200" "Factory directory deep"; then ((PASS++)); else ((FAIL++)); fi
+
+# Factory extension match
+if test_route "/factory/files/doc.txt" "200" "Factory extension match"; then ((PASS++)); else ((FAIL++)); fi
+if test_route "/factory/files/sub/readme.txt" "200" "Factory extension deep"; then ((PASS++)); else ((FAIL++)); fi
+
+echo ""
+echo "Testing case insensitive matching:"
+
+# Case insensitive exact
+if test_route "/case/exact" "200" "Case exact lowercase"; then ((PASS++)); else ((FAIL++)); fi
+if test_route "/CASE/EXACT" "200" "Case exact uppercase"; then ((PASS++)); else ((FAIL++)); fi
+if test_route "/Case/Exact" "200" "Case exact mixed"; then ((PASS++)); else ((FAIL++)); fi
+
+# Case insensitive prefix
+if test_route "/case/prefix" "200" "Case prefix lowercase"; then ((PASS++)); else ((FAIL++)); fi
+if test_route "/CASE/PREFIX-test" "200" "Case prefix uppercase"; then ((PASS++)); else ((FAIL++)); fi
+if test_route "/Case/Prefix/sub" "200" "Case prefix mixed"; then ((PASS++)); else ((FAIL++)); fi
+
+# Case insensitive directory
+if test_route "/case/dir/users" "200" "Case dir lowercase"; then ((PASS++)); else ((FAIL++)); fi
+if test_route "/CASE/DIR/admin" "200" "Case dir uppercase"; then ((PASS++)); else ((FAIL++)); fi
+if test_route "/Case/Dir/settings" "200" "Case dir mixed"; then ((PASS++)); else ((FAIL++)); fi
+
+# Case insensitive extension
+if test_route "/case/files/doc.pdf" "200" "Case ext lowercase"; then ((PASS++)); else ((FAIL++)); fi
+if test_route "/CASE/FILES/DOC.PDF" "200" "Case ext uppercase"; then ((PASS++)); else ((FAIL++)); fi
+if test_route "/Case/Files/Doc.Pdf" "200" "Case ext mixed"; then ((PASS++)); else ((FAIL++)); fi
+
+echo ""
+echo "Testing special matchers:"
+
+# Test POST to catch-all (all() matcher)
+echo -n "Testing POST /any/path (all matcher) ... "
+response=$(curl -s -X POST -w "HTTPSTATUS:%{http_code}" "$BASE_URL/any/path" 2>/dev/null)
+status_code=$(echo "$response" | grep -o "HTTPSTATUS:[0-9]*" | cut -d: -f2)
+if [ "$status_code" = "200" ]; then
+    echo "✅ PASS ($status_code)"
+    ((PASS++))
+else
+    echo "❌ FAIL (expected 200, got $status_code)"
+    ((FAIL++))
+fi
+
+# Check if regex is enabled by testing the server
+echo ""
+echo "Checking for regex support..."
+regex_test=$(curl -s "$BASE_URL/user/123" 2>/dev/null)
+if curl -s -w "%{http_code}" "$BASE_URL/user/123" 2>/dev/null | grep -q "200"; then
+    echo "Regex support detected - testing traditional regex routes:"
+    if test_route "/user/123" "200" "Traditional regex user ID"; then ((PASS++)); else ((FAIL++)); fi
+    if test_route "/user/456" "200" "Traditional regex user ID 2"; then ((PASS++)); else ((FAIL++)); fi
+    if test_route "/blog/2023/10/15" "200" "Traditional regex blog date"; then ((PASS++)); else ((FAIL++)); fi
+    if test_route "/blog/2024/12/25" "200" "Traditional regex blog date 2"; then ((PASS++)); else ((FAIL++)); fi
+
+    echo "Testing AsyncURIMatcher regex factory methods:"
+    if test_route "/factory/user/123" "200" "Factory regex user ID"; then ((PASS++)); else ((FAIL++)); fi
+    if test_route "/factory/user/789" "200" "Factory regex user ID 2"; then ((PASS++)); else ((FAIL++)); fi
+    if test_route "/factory/blog/2023/10/15" "200" "Factory regex blog date"; then ((PASS++)); else ((FAIL++)); fi
+    if test_route "/factory/blog/2024/12/31" "200" "Factory regex blog date 2"; then ((PASS++)); else ((FAIL++)); fi
+
+    # Case insensitive regex
+    if test_route "/factory/search/hello" "200" "Factory regex search lowercase"; then ((PASS++)); else ((FAIL++)); fi
+    if test_route "/FACTORY/SEARCH/WORLD" "200" "Factory regex search uppercase"; then ((PASS++)); else ((FAIL++)); fi
+    if test_route "/Factory/Search/Test" "200" "Factory regex search mixed"; then ((PASS++)); else ((FAIL++)); fi
+
+    # Test regex validation
+    if test_route "/user/abc" "404" "Invalid regex (letters instead of numbers)"; then ((PASS++)); else ((FAIL++)); fi
+    if test_route "/blog/23/10/15" "404" "Invalid regex (2-digit year)"; then ((PASS++)); else ((FAIL++)); fi
+    if test_route "/factory/user/abc" "404" "Factory regex invalid (letters)"; then ((PASS++)); else ((FAIL++)); fi
+else
+    echo "Regex support not detected (compile with ASYNCWEBSERVER_REGEX to enable)"
+fi
+
+echo ""
+echo "Testing routes that should fail (404 Not Found):"
+
+if test_route "/nonexistent" "404" "Non-existent route"; then ((PASS++)); else ((FAIL++)); fi
+
+# Test factory exact vs traditional behavior difference
+if test_route "/factory/exact/sub" "404" "Factory exact should NOT match subpaths"; then ((PASS++)); else ((FAIL++)); fi
+
+# Test factory directory requires trailing slash
+if test_route "/factory/dir" "404" "Factory directory should NOT match without trailing slash"; then ((PASS++)); else ((FAIL++)); fi
+
+# Test extension mismatch
+if test_route "/factory/files/doc.pdf" "404" "Factory extension mismatch (.pdf vs .txt)"; then ((PASS++)); else ((FAIL++)); fi
+
+# Test case sensitive when flag not used
+if test_route "/exact" "200" "Traditional exact lowercase"; then ((PASS++)); else ((FAIL++)); fi
+if test_route "/EXACT" "404" "Traditional exact should be case sensitive"; then ((PASS++)); else ((FAIL++)); fi
+
+echo ""
+echo "=================================="
+echo "Test Results:"
+echo "✅ Passed: $PASS"
+echo "❌ Failed: $FAIL"
+echo "Total: $((PASS + FAIL))"
+
+if [ $FAIL -eq 0 ]; then
+    echo ""
+    echo "🎉 All tests passed! URI matching is working correctly."
+    exit 0
+else
+    echo ""
+    echo "❌ Some tests failed. Check the server and routes."
+    exit 1
+fi

examples/Upload/Upload.ino

@@ -1,5 +1,5 @@
 // SPDX-License-Identifier: LGPL-3.0-or-later
-// Copyright 2016-2025 Hristo Gochkov, Mathieu Carbou, Emil Muratov
+// Copyright 2016-2026 Hristo Gochkov, Mathieu Carbou, Emil Muratov, Will Miles
 
 //
 // Demo text, binary and file upload
@@ -31,7 +31,7 @@ void setup() {
     LittleFS.begin();
   }
 
-#if SOC_WIFI_SUPPORTED || CONFIG_ESP_WIFI_REMOTE_ENABLED || LT_ARD_HAS_WIFI
+#if ASYNCWEBSERVER_WIFI_SUPPORTED
   WiFi.mode(WIFI_AP);
   WiFi.softAP("esp-captive");
 #endif
@@ -63,6 +63,7 @@ void setup() {
         if (!buffer->reserve(size)) {
           delete buffer;
           request->abort();
+          return;
         }
         request->_tempObject = buffer;
       }
@@ -100,6 +101,7 @@ void setup() {
 
         if (!request->_tempFile) {
           request->send(400, "text/plain", "File not available for writing");
+          return;
         }
       }
       if (len) {
@@ -141,6 +143,7 @@ void setup() {
 
       // first pass ?
       if (!index) {
+        // Note: using content type to determine size is not reliable!
         size_t size = request->header("Content-Length").toInt();
         if (!size) {
           request->send(400, "text/plain", "No Content-Length");
@@ -150,6 +153,7 @@ void setup() {
           if (!buffer) {
             // not enough memory
             request->abort();
+            return;
           } else {
             request->_tempObject = buffer;
           }

examples/UploadFlash/UploadFlash.ino

@@ -0,0 +1,158 @@
+// SPDX-License-Identifier: LGPL-3.0-or-later
+// Copyright 2016-2026 Hristo Gochkov, Mathieu Carbou, Emil Muratov, Will Miles
+
+//
+// Demo to upload a firmware and filesystem image via multipart form data
+//
+
+#include <Arduino.h>
+#if defined(ESP32) || defined(LIBRETINY)
+#include <AsyncTCP.h>
+#include <WiFi.h>
+#elif defined(ESP8266)
+#include <ESP8266WiFi.h>
+#include <ESPAsyncTCP.h>
+#elif defined(TARGET_RP2040) || defined(TARGET_RP2350) || defined(PICO_RP2040) || defined(PICO_RP2350)
+#include <RPAsyncTCP.h>
+#include <WiFi.h>
+#endif
+
+#include <ESPAsyncWebServer.h>
+#include <StreamString.h>
+#include <LittleFS.h>
+
+// ESP32 example ONLY
+#ifdef ESP32
+#include <Update.h>
+#endif
+
+static AsyncWebServer server(80);
+
+void setup() {
+  Serial.begin(115200);
+
+  if (!LittleFS.begin()) {
+    LittleFS.format();
+    LittleFS.begin();
+  }
+
+#if ASYNCWEBSERVER_WIFI_SUPPORTED
+  WiFi.mode(WIFI_AP);
+  WiFi.softAP("esp-captive");
+#endif
+
+// ESP32 example ONLY
+#ifdef ESP32
+
+  // Shows how to get the fw and fs  (names) and filenames from a multipart upload,
+  // and also how to handle multiple file uploads in a single request.
+  //
+  // This example also shows how to pass and handle different parameters having the same name in query string, post form and content-disposition.
+  //
+  // Execute in the terminal, in order:
+  //
+  // 1. Build firmware: pio run -e arduino-3
+  // 2. Build FS image: pio run -e arduino-3 -t buildfs
+  // 3. Flash both at the same time: curl -v -F "name=Bob" -F "fw=@.pio/build/arduino-3/firmware.bin" -F "fs=@.pio/build/arduino-3/littlefs.bin" http://192.168.4.1/flash?name=Bill
+  //
+  server.on(
+    "/flash", HTTP_POST,
+    [](AsyncWebServerRequest *request) {
+      if (request->getResponse()) {
+        // response already created
+        return;
+      }
+
+      // list all parameters
+      Serial.println("Request parameters:");
+      const size_t params = request->params();
+      for (size_t i = 0; i < params; i++) {
+        const AsyncWebParameter *p = request->getParam(i);
+        Serial.printf("Param[%u]: %s=%s, isPost=%d, isFile=%d, size=%u\n", i, p->name().c_str(), p->value().c_str(), p->isPost(), p->isFile(), p->size());
+      }
+
+      Serial.println("Flash / Filesystem upload completed");
+
+      request->send(200, "text/plain", "Upload complete");
+    },
+    [](AsyncWebServerRequest *request, String filename, size_t index, uint8_t *data, size_t len, bool final) {
+      Serial.printf("Upload[%s]: index=%u, len=%u, final=%d\n", filename.c_str(), index, len, final);
+
+      if (request->getResponse() != nullptr) {
+        // upload aborted
+        return;
+      }
+
+      // start a new content-disposition upload
+      if (!index) {
+        // list all parameters
+        const size_t params = request->params();
+        for (size_t i = 0; i < params; i++) {
+          const AsyncWebParameter *p = request->getParam(i);
+          Serial.printf("Param[%u]: %s=%s, isPost=%d, isFile=%d, size=%u\n", i, p->name().c_str(), p->value().c_str(), p->isPost(), p->isFile(), p->size());
+        }
+
+        // get the content-disposition parameter
+        const AsyncWebParameter *p = request->getParam(asyncsrv::T_name, true, true);
+        if (p == nullptr) {
+          request->send(400, "text/plain", "Missing content-disposition 'name' parameter");
+          return;
+        }
+
+        // determine upload type based on the parameter name
+        if (p->value() == "fs") {
+          Serial.printf("Filesystem image upload for file: %s\n", filename.c_str());
+          if (!Update.begin(UPDATE_SIZE_UNKNOWN, U_SPIFFS)) {
+            Update.printError(Serial);
+            request->send(400, "text/plain", "Update begin failed");
+            return;
+          }
+
+        } else if (p->value() == "fw") {
+          Serial.printf("Firmware image upload for file: %s\n", filename.c_str());
+          if (!Update.begin(UPDATE_SIZE_UNKNOWN, U_FLASH)) {
+            Update.printError(Serial);
+            request->send(400, "text/plain", "Update begin failed");
+            return;
+          }
+
+        } else {
+          Serial.printf("Unknown upload type for file: %s\n", filename.c_str());
+          request->send(400, "text/plain", "Unknown upload type");
+          return;
+        }
+      }
+
+      // some bytes to write ?
+      if (len) {
+        if (Update.write(data, len) != len) {
+          Update.printError(Serial);
+          Update.end();
+          request->send(400, "text/plain", "Update write failed");
+          return;
+        }
+      }
+
+      // finish the content-disposition upload
+      if (final) {
+        if (!Update.end(true)) {
+          Update.printError(Serial);
+          request->send(400, "text/plain", "Update end failed");
+          return;
+        }
+
+        // success response is created in the final request handler when all uploads are completed
+        Serial.printf("Upload success of file %s\n", filename.c_str());
+      }
+    }
+  );
+
+#endif
+
+  server.begin();
+}
+
+// not needed
+void loop() {
+  delay(100);
+}

examples/WebSocket/WebSocket.ino

@@ -1,5 +1,5 @@
 // SPDX-License-Identifier: LGPL-3.0-or-later
-// Copyright 2016-2025 Hristo Gochkov, Mathieu Carbou, Emil Muratov
+// Copyright 2016-2026 Hristo Gochkov, Mathieu Carbou, Emil Muratov, Will Miles
 
 //
 // WebSocket example
@@ -19,17 +19,58 @@
 
 #include <ESPAsyncWebServer.h>
 
+static const char *htmlContent PROGMEM = R"(
+<!DOCTYPE html>
+<html>
+<head>
+  <title>WebSocket</title>
+</head>
+<body>
+  <h1>WebSocket Example</h1>
+  <p>Open your browser console!</p>
+  <input type="text" id="message" placeholder="Type a message">
+  <button onclick='sendMessage()'>Send</button>
+  <script>
+    var ws = new WebSocket('ws://192.168.4.1/ws');
+    ws.onopen = function() {
+      console.log("WebSocket connected");
+    };
+    ws.onmessage = function(event) {
+      console.log("WebSocket message: " + event.data);
+    };
+    ws.onclose = function() {
+      console.log("WebSocket closed");
+    };
+    ws.onerror = function(error) {
+      console.log("WebSocket error: " + error);
+    };
+    function sendMessage() {
+      var message = document.getElementById("message").value;
+      ws.send(message);
+      console.log("WebSocket sent: " + message);
+    }
+  </script>
+</body>
+</html>
+  )";
+static const size_t htmlContentLength = strlen_P(htmlContent);
+
 static AsyncWebServer server(80);
 static AsyncWebSocket ws("/ws");
 
 void setup() {
   Serial.begin(115200);
 
-#if SOC_WIFI_SUPPORTED || CONFIG_ESP_WIFI_REMOTE_ENABLED || LT_ARD_HAS_WIFI
+#if ASYNCWEBSERVER_WIFI_SUPPORTED
   WiFi.mode(WIFI_AP);
   WiFi.softAP("esp-captive");
 #endif
 
+  // serves root html page
+  server.on("/", HTTP_GET, [](AsyncWebServerRequest *request) {
+    request->send(200, "text/html", (const uint8_t *)htmlContent, htmlContentLength);
+  });
+
   //
   // Run in terminal 1: websocat ws://192.168.4.1/ws => should stream data
   // Run in terminal 2: websocat ws://192.168.4.1/ws => should stream data
@@ -66,6 +107,7 @@ void setup() {
         if (info->opcode == WS_TEXT) {
           data[len] = 0;
           Serial.printf("ws text: %s\n", (char *)data);
+          client->ping();
         }
       }
     }

examples/WebSocketEasy/WebSocketEasy.ino

@@ -1,5 +1,5 @@
 // SPDX-License-Identifier: LGPL-3.0-or-later
-// Copyright 2016-2025 Hristo Gochkov, Mathieu Carbou, Emil Muratov
+// Copyright 2016-2026 Hristo Gochkov, Mathieu Carbou, Emil Muratov, Will Miles
 
 //
 // WebSocket example using the easy to use AsyncWebSocketMessageHandler handler that only supports unfragmented messages
@@ -40,7 +40,7 @@ static const char *htmlContent PROGMEM = R"(
 </head>
 <body>
   <h1>WebSocket Example</h1>
-  <>Open your browser console!</p>
+  <p>Open your browser console!</p>
   <input type="text" id="message" placeholder="Type a message">
   <button onclick='sendMessage()'>Send</button>
   <script>
@@ -71,7 +71,7 @@ static const size_t htmlContentLength = strlen_P(htmlContent);
 void setup() {
   Serial.begin(115200);
 
-#if SOC_WIFI_SUPPORTED || CONFIG_ESP_WIFI_REMOTE_ENABLED || LT_ARD_HAS_WIFI
+#if ASYNCWEBSERVER_WIFI_SUPPORTED
   WiFi.mode(WIFI_AP);
   WiFi.softAP("esp-captive");
 #endif
@@ -97,6 +97,7 @@ void setup() {
 
   wsHandler.onMessage([](AsyncWebSocket *server, AsyncWebSocketClient *client, const uint8_t *data, size_t len) {
     Serial.printf("Client %" PRIu32 " data: %s\n", client->id(), (const char *)data);
+    server->textAll(data, len);
   });
 
   wsHandler.onFragment([](AsyncWebSocket *server, AsyncWebSocketClient *client, const AwsFrameInfo *frameInfo, const uint8_t *data, size_t len) {