diff --git a/.github/workflows/tests.yml b/.github/workflows/tests.yml
index 2667238..8039e8a 100644
--- a/.github/workflows/tests.yml
+++ b/.github/workflows/tests.yml
@@ -13,7 +13,7 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        php: [ "7.4", "8.0", "8.1", "8.2", "8.3", "8.4" ]
+        php: [ "7.4", "8.0", "8.1", "8.2", "8.3", "8.4", "8.5" ]
 
     steps:
       - uses: actions/checkout@v4
diff --git a/README.md b/README.md
index 528bf8e..15d14c5 100644
--- a/README.md
+++ b/README.md
@@ -123,6 +123,7 @@ The command writes one JSON event per line, each prefixed with
 `TWEAKPHP_STREAM:`:
 
 ```text
+TWEAKPHP_STREAM:{"type":"started","pid":1234}
 TWEAKPHP_STREAM:{"type":"statement.started","index":0,"line":2,"code":"echo \"First\";"}
 TWEAKPHP_STREAM:{"type":"output","index":0,"data":"First"}
 TWEAKPHP_STREAM:{"type":"statement.completed","index":0,"queries":[]}
@@ -131,6 +132,10 @@ TWEAKPHP_STREAM:{"type":"completed"}
 
 Event types:
 
+- `started`: the client started. It is emitted as the first line, before the
+  project's framework bootstraps, so callers can stop the process even when
+  bootstrapping hangs. It includes the client process id as `pid`; `pid` is
+  omitted when unavailable.
 - `statement.started`: a statement started
 - `output`: the statement produced output. Presenter output also includes an
   `html` field containing the rendered HTML fragment; plain `echo` output only
diff --git a/index.php b/index.php
index 9648a80..1305824 100644
--- a/index.php
+++ b/index.php
@@ -63,6 +63,15 @@
     echo 'TWEAKPHP_ERROR:'.json_encode($error, JSON_INVALID_UTF8_SUBSTITUTE).PHP_EOL;
 };
 
+if ($command === 'execute-stream') {
+    $started = ['type' => 'started'];
+    $pid = getmypid();
+    if ($pid !== false && $pid > 0) {
+        $started['pid'] = (int) $pid;
+    }
+    $writeStreamEvent($started);
+}
+
 $customLoader = Cli::getArgument('loader');
 try {
     QueryCollector::enable(filter_var(Cli::getArgument('query-log'), FILTER_VALIDATE_BOOL));
diff --git a/tests/ExecuteStreamTest.php b/tests/ExecuteStreamTest.php
new file mode 100644
index 0000000..8d9fc9c
--- /dev/null
+++ b/tests/ExecuteStreamTest.php
@@ -0,0 +1,79 @@
+<?php
+
+namespace TweakPHP\Client\Tests;
+
+use PHPUnit\Framework\TestCase;
+
+class ExecuteStreamTest extends TestCase
+{
+    public function test_started_event_with_pid_is_the_first_stream_line()
+    {
+        $lines = $this->runClient('execute-stream', 'echo 1;');
+
+        $this->assertStringStartsWith('TWEAKPHP_STREAM:', $lines[0]);
+
+        $event = json_decode(substr($lines[0], strlen('TWEAKPHP_STREAM:')), true);
+        $this->assertSame(JSON_ERROR_NONE, json_last_error());
+        $this->assertSame('started', $event['type']);
+        $this->assertArrayHasKey('pid', $event);
+        $this->assertIsInt($event['pid']);
+        $this->assertGreaterThan(0, $event['pid']);
+    }
+
+    public function test_execute_stream_emits_the_full_event_sequence()
+    {
+        $lines = $this->runClient('execute-stream', 'echo 1;');
+
+        $types = [];
+        foreach ($lines as $line) {
+            $this->assertStringStartsWith('TWEAKPHP_STREAM:', $line);
+
+            $event = json_decode(substr($line, strlen('TWEAKPHP_STREAM:')), true);
+            $this->assertSame(JSON_ERROR_NONE, json_last_error());
+            $types[] = $event['type'];
+        }
+
+        $this->assertSame(
+            ['started', 'statement.started', 'output', 'statement.completed', 'completed'],
+            $types
+        );
+    }
+
+    public function test_execute_does_not_emit_stream_events()
+    {
+        $lines = $this->runClient('execute', 'echo 1;');
+
+        $this->assertNotEmpty($lines);
+        $this->assertStringStartsWith('TWEAKPHP_RESULT:', $lines[0]);
+
+        foreach ($lines as $line) {
+            $this->assertStringNotContainsString('TWEAKPHP_STREAM:', $line);
+        }
+    }
+
+    private function runClient(string $command, string $code): array
+    {
+        $projectPath = sys_get_temp_dir().'/tweakphp-client-test-'.uniqid();
+        mkdir($projectPath);
+
+        try {
+            $executable = sprintf(
+                '%s %s %s %s %s 2>/dev/null',
+                escapeshellarg(PHP_BINARY),
+                escapeshellarg(__DIR__.'/../index.php'),
+                escapeshellarg($projectPath),
+                escapeshellarg($command),
+                escapeshellarg(base64_encode($code))
+            );
+
+            exec($executable, $lines, $exitCode);
+
+            $this->assertSame(0, $exitCode);
+            $this->assertNotEmpty($lines);
+
+            return $lines;
+        } finally {
+            @rmdir($projectPath);
+        }
+    }
+}