diff --git a/config/ext.json b/config/ext.json
index 19e33836b..e74f64af1 100644
--- a/config/ext.json
+++ b/config/ext.json
@@ -382,6 +382,11 @@
     "shmop": {
         "type": "builtin"
     },
+    "simdjson": {
+        "type": "external",
+        "source": "ext-simdjson",
+        "cpp-extension": true
+    },
     "simplexml": {
         "type": "builtin",
         "arg-type": "custom",
diff --git a/config/source.json b/config/source.json
index 6b3ca4141..6ed35f5de 100644
--- a/config/source.json
+++ b/config/source.json
@@ -100,6 +100,16 @@
             "path": "LICENSE"
         }
     },
+    "ext-simdjson": {
+        "type": "url",
+        "url": "https://pecl.php.net/get/simdjson",
+        "path": "php-src/ext/simdjson",
+        "filename": "simdjson.tgz",
+        "license": {
+            "type": "file",
+            "path": "LICENSE"
+        }
+    },
     "ext-snappy": {
         "type": "git",
         "path": "php-src/ext/snappy",
diff --git a/src/SPC/builder/extension/simdjson.php b/src/SPC/builder/extension/simdjson.php
new file mode 100644
index 000000000..71796ebee
--- /dev/null
+++ b/src/SPC/builder/extension/simdjson.php
@@ -0,0 +1,34 @@
+<?php
+
+declare(strict_types=1);
+
+namespace SPC\builder\extension;
+
+use SPC\builder\Extension;
+use SPC\store\FileSystem;
+use SPC\util\CustomExt;
+
+#[CustomExt('simdjson')]
+class simdjson extends Extension
+{
+    public function patchBeforeBuildconf(): bool
+    {
+        $php_ver = $this->builder->getPHPVersionID();
+        FileSystem::replaceFileRegex(
+            SOURCE_PATH . '/php-src/ext/simdjson/config.m4',
+            '/php_version=(`.*`)$/m',
+            'php_version=' . strval($php_ver)
+        );
+        FileSystem::replaceFileStr(
+            SOURCE_PATH . '/php-src/ext/simdjson/config.m4',
+            'if test -z "$PHP_CONFIG"; then',
+            'if false; then'
+        );
+        FileSystem::replaceFileStr(
+            SOURCE_PATH . '/php-src/ext/simdjson/config.w32',
+            "'yes',",
+            'PHP_SIMDJSON_SHARED,'
+        );
+        return true;
+    }
+}
diff --git a/src/globals/test-extensions.php b/src/globals/test-extensions.php
index 9cdaaf606..e2aa441e1 100644
--- a/src/globals/test-extensions.php
+++ b/src/globals/test-extensions.php
@@ -13,8 +13,8 @@
 
 // If you want to test your added extensions and libs, add below (comma separated, example `bcmath,openssl`).
 $extensions = match (PHP_OS_FAMILY) {
-    'Linux', 'Darwin' => 'ds',
-    'Windows' => 'mbstring,pdo_sqlite,mbregex,ffi,ds',
+    'Linux', 'Darwin' => 'ds,simdjson',
+    'Windows' => 'mbstring,pdo_sqlite,mbregex,ffi,ds,simdjson',
 };
 
 // If you want to test lib-suggests feature with extension, add them below (comma separated, example `libwebp,libavif`).