diff --git a/docs/capabilities.md b/docs/capabilities.md
index fca87d57..94864e0f 100644
--- a/docs/capabilities.md
+++ b/docs/capabilities.md
@@ -74,7 +74,7 @@ Auto-generated by `script/capability-matrix.php`. Do not edit by hand.
 | `is_object` | yes | yes | yes | types |  |
 | `is_scalar` | yes | yes | yes | standard |  |
 | `is_string` | yes | yes | yes | types | JIT PHPT |
-| `json_encode` | yes | yes | yes | standard | JIT PHPT |
+| `json_encode` | yes | yes | yes | standard | JIT PHPT; AOT PHPT |
 | `lcfirst` | yes | yes | yes | standard |  |
 | `log` | yes | yes | yes | standard |  |
 | `ltrim` | yes | yes | yes | standard | AOT PHPT |
diff --git a/test/aot/ExampleWebAotTest.php b/test/aot/ExampleWebAotTest.php
index 74f87cc4..f47886e0 100644
--- a/test/aot/ExampleWebAotTest.php
+++ b/test/aot/ExampleWebAotTest.php
@@ -64,6 +64,17 @@ public function testStaticWebExampleFile(): void
         $this->assertStringContainsString('<h1>Hello World</h1>', $result);
     }
 
+    public function testApiJsonExampleFile(): void
+    {
+        $source = realpath(__DIR__ . '/../../examples/004-ApiJson/example.php');
+        $this->assertNotFalse($source);
+        $result = $this->compileAndRun($source, []);
+        $this->assertStringContainsString('Content-Type: application/json', $result);
+        $this->assertStringContainsString('Status: 200', $result);
+        $this->assertStringContainsString('"ok":true', $result);
+        $this->assertStringContainsString('php-compiler', $result);
+    }
+
     /**
      * @param list<string> $compileExtraArgs
      */
diff --git a/test/fixtures/aot/cases/json_encode_api.phpt b/test/fixtures/aot/cases/json_encode_api.phpt
new file mode 100644
index 00000000..5b627b74
--- /dev/null
+++ b/test/fixtures/aot/cases/json_encode_api.phpt
@@ -0,0 +1,13 @@
+--TEST--
+AOT: json_encode API body with Content-Type and Status 200 (issues #61, #270)
+--FILE--
+<?php
+header('Content-Type: application/json');
+http_response_code(200);
+echo json_encode(['ok' => true, 'service' => 'php-compiler']);
+--EXPECT--
+Content-Type: application/json
+Status: 200
+{"ok":true,"service":"php-compiler"}
+--EXPECT_EXIT--
+0
diff --git a/test/unit/ExamplesCompileTest.php b/test/unit/ExamplesCompileTest.php
index 79e19596..523f6ba8 100644
--- a/test/unit/ExamplesCompileTest.php
+++ b/test/unit/ExamplesCompileTest.php
@@ -239,6 +239,37 @@ public function testAotExecuteSimpleWebPost(): void
         @unlink($binary);
     }
 
+    /**
+     * Shipped 004-ApiJson: compile.php -o temp binary — json_encode + http_response_code(200) AOT smoke.
+     *
+     * @group llvm
+     * @group aot
+     *
+     * @see https://github.com/PurHur/php-compiler/issues/270
+     */
+    public function testAotExecuteSmoke004ApiJson(): void
+    {
+        if (!self::isLlvmReady()) {
+            $this->markTestSkipped(
+                'LLVM 9 toolchain not available. Run script/install-llvm9.sh from the repository root.'
+            );
+        }
+        $repoRoot = dirname(__DIR__, 2);
+        $source = realpath($repoRoot.'/examples/004-ApiJson/example.php');
+        $this->assertNotFalse($source);
+
+        $env = $this->llvmProcessEnv($repoRoot);
+        $binary = $this->compileAotBinaryNoQueryBaking($source, $repoRoot, $env);
+        $out = $this->runAotBinary($binary, $env);
+        $this->assertStringContainsString('Content-Type: application/json', $out);
+        $this->assertStringContainsString('Status: 200', $out);
+        foreach (self::smokeNeedles('004-ApiJson') as $needle) {
+            $this->assertStringContainsString($needle, $out);
+        }
+
+        @unlink($binary);
+    }
+
     /**
      * Shipped 002-StaticWeb: compile.php -o temp binary, run once — AOT link + runtime smoke (no superglobals).
      *