diff --git a/Zend/tests/phpc/001_basic.phpt b/Zend/tests/phpc/001_basic.phpt
new file mode 100644
index 000000000000..ea7bb882255f
--- /dev/null
+++ b/Zend/tests/phpc/001_basic.phpt
@@ -0,0 +1,12 @@
+--TEST--
+.phpc: a file without <?php is parsed as pure PHP
+--FILE--
+<?php
+$file = __DIR__ . '/' . basename(__FILE__, '.php') . '.phpc';
+file_put_contents($file, 'echo "hello\n"; $x = 1 + 2; echo $x, "\n";');
+register_shutdown_function(fn() => @unlink($file));
+require $file;
+?>
+--EXPECT--
+hello
+3
diff --git a/Zend/tests/phpc/002_php_unchanged.phpt b/Zend/tests/phpc/002_php_unchanged.phpt
new file mode 100644
index 000000000000..e0a1439bddce
--- /dev/null
+++ b/Zend/tests/phpc/002_php_unchanged.phpt
@@ -0,0 +1,12 @@
+--TEST--
+.phpc: classic .php behavior is completely unaffected (BC sanity check)
+--FILE--
+<?php
+$file = __DIR__ . '/' . basename(__FILE__, '.php') . '_payload.php';
+/* Same payload as .phpc test, but written to a .php file. */
+file_put_contents($file, 'echo "hello\n"; $x = 1 + 2; echo $x, "\n";');
+register_shutdown_function(fn() => @unlink($file));
+require $file;
+?>
+--EXPECT--
+echo "hello\n"; $x = 1 + 2; echo $x, "\n";
diff --git a/Zend/tests/phpc/003_phpc_requires_php.phpt b/Zend/tests/phpc/003_phpc_requires_php.phpt
new file mode 100644
index 000000000000..0d4f0a3a506d
--- /dev/null
+++ b/Zend/tests/phpc/003_phpc_requires_php.phpt
@@ -0,0 +1,15 @@
+--TEST--
+.phpc: a pure-PHP file can require a classic .php file
+--FILE--
+<?php
+$dir = __DIR__;
+$base = basename(__FILE__, '.php');
+$phpc = "$dir/{$base}_main.phpc";
+$php  = "$dir/{$base}_lib.php";
+file_put_contents($php,  '<?php function greet(string $w): string { return "hi, $w"; }');
+file_put_contents($phpc, "require '$php';\necho greet('world'), \"\\n\";");
+register_shutdown_function(function () use ($phpc, $php) { @unlink($phpc); @unlink($php); });
+require $phpc;
+?>
+--EXPECT--
+hi, world
diff --git a/Zend/tests/phpc/004_php_requires_phpc.phpt b/Zend/tests/phpc/004_php_requires_phpc.phpt
new file mode 100644
index 000000000000..2be149c00fd0
--- /dev/null
+++ b/Zend/tests/phpc/004_php_requires_phpc.phpt
@@ -0,0 +1,14 @@
+--TEST--
+.phpc: a classic .php file can require a .phpc file
+--FILE--
+<?php
+$dir = __DIR__;
+$base = basename(__FILE__, '.php');
+$phpc = "$dir/{$base}_lib.phpc";
+file_put_contents($phpc, "function add(int \$a, int \$b): int { return \$a + \$b; }");
+register_shutdown_function(fn() => @unlink($phpc));
+require $phpc;
+echo add(2, 3), "\n";
+?>
+--EXPECT--
+5
diff --git a/Zend/tests/phpc/005_utf8_bom.phpt b/Zend/tests/phpc/005_utf8_bom.phpt
new file mode 100644
index 000000000000..eb367e21af4d
--- /dev/null
+++ b/Zend/tests/phpc/005_utf8_bom.phpt
@@ -0,0 +1,11 @@
+--TEST--
+.phpc: a leading UTF-8 BOM is silently skipped
+--FILE--
+<?php
+$file = __DIR__ . '/' . basename(__FILE__, '.php') . '.phpc';
+file_put_contents($file, "\xEF\xBB\xBF" . 'echo "bom-ok\n";');
+register_shutdown_function(fn() => @unlink($file));
+require $file;
+?>
+--EXPECT--
+bom-ok
diff --git a/Zend/tests/phpc/006_halt_compiler.phpt b/Zend/tests/phpc/006_halt_compiler.phpt
new file mode 100644
index 000000000000..bae629a88edf
--- /dev/null
+++ b/Zend/tests/phpc/006_halt_compiler.phpt
@@ -0,0 +1,25 @@
+--TEST--
+.phpc: __halt_compiler() works and __COMPILER_HALT_OFFSET__ points to trailing data
+--FILE--
+<?php
+$file = __DIR__ . '/' . basename(__FILE__, '.php') . '.phpc';
+/* The .phpc file echoes a marker, halts the compiler, and the driver here
+ * reads what comes after __halt_compiler() back via the offset constant
+ * (which __halt_compiler() exposes in the loaded file's namespace). */
+$code = <<<'PHPC'
+$offset = __COMPILER_HALT_OFFSET__;
+$fh = fopen(__FILE__, 'rb');
+fseek($fh, $offset);
+$trail = trim(fread($fh, 8192));
+fclose($fh);
+echo "before-halt\n", $trail, "\n";
+__halt_compiler();
+TRAILING-DATA-12345
+PHPC;
+file_put_contents($file, $code);
+register_shutdown_function(fn() => @unlink($file));
+require $file;
+?>
+--EXPECT--
+before-halt
+TRAILING-DATA-12345
diff --git a/Zend/tests/phpc/007_closing_tag.phpt b/Zend/tests/phpc/007_closing_tag.phpt
new file mode 100644
index 000000000000..f458ce937c30
--- /dev/null
+++ b/Zend/tests/phpc/007_closing_tag.phpt
@@ -0,0 +1,13 @@
+--TEST--
+.phpc: ?> in a .phpc file drops to inline output, mirroring .php semantics
+--FILE--
+<?php
+$file = __DIR__ . '/' . basename(__FILE__, '.php') . '.phpc';
+file_put_contents($file, "echo \"from-phpc\\n\";\n?>\nplain inline content\n<?php echo \"back\\n\";");
+register_shutdown_function(fn() => @unlink($file));
+require $file;
+?>
+--EXPECT--
+from-phpc
+plain inline content
+back
diff --git a/Zend/tests/phpc/008_empty.phpt b/Zend/tests/phpc/008_empty.phpt
new file mode 100644
index 000000000000..c82ce5326bec
--- /dev/null
+++ b/Zend/tests/phpc/008_empty.phpt
@@ -0,0 +1,12 @@
+--TEST--
+.phpc: an empty file produces no output and no error
+--FILE--
+<?php
+$file = __DIR__ . '/' . basename(__FILE__, '.php') . '.phpc';
+file_put_contents($file, '');
+register_shutdown_function(fn() => @unlink($file));
+require $file;
+echo "after-require\n";
+?>
+--EXPECT--
+after-require
diff --git a/Zend/tests/phpc/009_declare_strict_types.phpt b/Zend/tests/phpc/009_declare_strict_types.phpt
new file mode 100644
index 000000000000..81745d6772f9
--- /dev/null
+++ b/Zend/tests/phpc/009_declare_strict_types.phpt
@@ -0,0 +1,11 @@
+--TEST--
+.phpc: declare(strict_types=1) works as first statement in a .phpc file
+--FILE--
+<?php
+$file = __DIR__ . '/' . basename(__FILE__, '.php') . '.phpc';
+file_put_contents($file, "declare(strict_types=1);\nfunction add(int \$a, int \$b): int { return \$a + \$b; }\necho add(1, 2), \"\\n\";");
+register_shutdown_function(fn() => @unlink($file));
+require $file;
+?>
+--EXPECT--
+3
diff --git a/Zend/tests/phpc/010_class_definition.phpt b/Zend/tests/phpc/010_class_definition.phpt
new file mode 100644
index 000000000000..01e3ca10635f
--- /dev/null
+++ b/Zend/tests/phpc/010_class_definition.phpt
@@ -0,0 +1,20 @@
+--TEST--
+.phpc: class definitions and namespaces work in a .phpc file
+--FILE--
+<?php
+$file = __DIR__ . '/' . basename(__FILE__, '.php') . '.phpc';
+file_put_contents($file, <<<'PHPC'
+namespace App\Demo;
+
+class Greeter {
+    public function __construct(private string $who) {}
+    public function hello(): string { return "hello, {$this->who}"; }
+}
+
+echo (new Greeter('world'))->hello(), "\n";
+PHPC);
+register_shutdown_function(fn() => @unlink($file));
+require $file;
+?>
+--EXPECT--
+hello, world
diff --git a/Zend/tests/phpc/011_eval_unchanged.phpt b/Zend/tests/phpc/011_eval_unchanged.phpt
new file mode 100644
index 000000000000..fce79e171a55
--- /dev/null
+++ b/Zend/tests/phpc/011_eval_unchanged.phpt
@@ -0,0 +1,11 @@
+--TEST--
+.phpc: eval() is unaffected — string compile path is independent of file extension
+--FILE--
+<?php
+/* eval() always uses ZEND_COMPILE_POSITION_AFTER_OPEN_TAG, which already
+ * starts in ST_IN_SCRIPTING. .phpc semantics live in the file-compile
+ * path and must not leak into the string-compile path. */
+eval('echo "eval-ok\n";');
+?>
+--EXPECT--
+eval-ok
diff --git a/Zend/tests/phpc/012_token_get_all_unchanged.phpt b/Zend/tests/phpc/012_token_get_all_unchanged.phpt
new file mode 100644
index 000000000000..4a36c039c1cf
--- /dev/null
+++ b/Zend/tests/phpc/012_token_get_all_unchanged.phpt
@@ -0,0 +1,16 @@
+--TEST--
+.phpc: token_get_all() string path is unaffected (still requires <?php)
+--FILE--
+<?php
+$tokens = token_get_all("<?php echo 1;");
+foreach ($tokens as $t) {
+    if (is_array($t)) {
+        echo token_name($t[0]), "\n";
+    }
+}
+?>
+--EXPECT--
+T_OPEN_TAG
+T_ECHO
+T_WHITESPACE
+T_LNUMBER
diff --git a/Zend/tests/phpc/013_shebang_main_script.phpt b/Zend/tests/phpc/013_shebang_main_script.phpt
new file mode 100644
index 000000000000..fadb9f8c5e6e
--- /dev/null
+++ b/Zend/tests/phpc/013_shebang_main_script.phpt
@@ -0,0 +1,17 @@
+--TEST--
+.phpc: a CLI shebang line at the top of a .phpc main script is silently skipped
+--FILE--
+<?php
+$dir = sys_get_temp_dir();
+$file = $dir . '/' . basename(__FILE__, '.php') . '_main.phpc';
+file_put_contents($file,
+    "#!/usr/bin/env php\necho \"shebang-skipped\\n\"; echo __LINE__, \"\\n\";");
+register_shutdown_function(fn() => @unlink($file));
+
+$php = PHP_BINARY;
+$out = shell_exec(escapeshellarg($php) . ' -n ' . escapeshellarg($file));
+echo $out;
+?>
+--EXPECT--
+shebang-skipped
+2
diff --git a/Zend/tests/phpc/014_phpc_with_open_tag.phpt b/Zend/tests/phpc/014_phpc_with_open_tag.phpt
new file mode 100644
index 000000000000..88cbc93dceb6
--- /dev/null
+++ b/Zend/tests/phpc/014_phpc_with_open_tag.phpt
@@ -0,0 +1,18 @@
+--TEST--
+.phpc: an accidental literal '<?php' inside a .phpc file is a syntax error (not magic)
+--FILE--
+<?php
+$file = __DIR__ . '/' . basename(__FILE__, '.php') . '.phpc';
+/* In .phpc mode the lexer starts in ST_IN_SCRIPTING. A literal '<?php' at
+ * the top is now interpreted as code, not an opening tag, and is a
+ * syntax error. This guards against authors accidentally double-opening. */
+file_put_contents($file, "<?php\necho \"this-must-fail\";\n");
+register_shutdown_function(fn() => @unlink($file));
+try {
+    require $file;
+} catch (\ParseError $e) {
+    echo "ParseError: ", $e->getMessage(), "\n";
+}
+?>
+--EXPECTF--
+ParseError: syntax error, %s
diff --git a/Zend/tests/phpc/015_php_with_phpc_substring.phpt b/Zend/tests/phpc/015_php_with_phpc_substring.phpt
new file mode 100644
index 000000000000..bbe2e49b346c
--- /dev/null
+++ b/Zend/tests/phpc/015_php_with_phpc_substring.phpt
@@ -0,0 +1,23 @@
+--TEST--
+.phpc: extension match is strict; ".phpcc" or ".php" with "phpc" in middle are NOT .phpc
+--FILE--
+<?php
+$dir = __DIR__;
+$base = basename(__FILE__, '.php');
+
+/* Filename containing "phpc" but not ending in ".phpc" must NOT trigger
+ * pure-PHP mode. */
+$f1 = "$dir/{$base}_phpc.php";
+file_put_contents($f1, 'echo "must-stay-inline";');
+register_shutdown_function(fn() => @unlink($f1));
+require $f1;
+echo "\n";
+
+$f2 = "$dir/{$base}.phpcc";
+file_put_contents($f2, 'echo "must-stay-inline-too";');
+register_shutdown_function(fn() => @unlink($f2));
+require $f2;
+?>
+--EXPECT--
+echo "must-stay-inline";
+echo "must-stay-inline-too";
diff --git a/Zend/zend_language_scanner.l b/Zend/zend_language_scanner.l
index 07f2d44cb5c6..91122f73c619 100644
--- a/Zend/zend_language_scanner.l
+++ b/Zend/zend_language_scanner.l
@@ -567,7 +567,58 @@ ZEND_API zend_result open_file_for_scanning(zend_file_handle *file_handle)
 		zend_error_noreturn(E_COMPILE_ERROR, "zend_stream_mmap() failed");
 	}
 
-	if (CG(skip_shebang)) {
+	/* Pure-code PHP files via .phpc extension (RFC: optional_php_tags).
+	 *
+	 * Files whose name ends in ".phpc" are parsed as pure PHP: the lexer
+	 * starts directly in ST_IN_SCRIPTING, with no opening "<?php" required.
+	 * A leading UTF-8 BOM and an optional CLI shebang line (#!.*\n) are
+	 * silently skipped. The closing tag "?>" and __halt_compiler() retain
+	 * their current semantics, so a .phpc file remains free to drop into
+	 * inline output mode or terminate compilation, if desired.
+	 *
+	 * Files whose name does NOT end in ".phpc" (in particular: every .php
+	 * file, every .phar entry, every stream wrapper without a .phpc name,
+	 * every eval()/stdin/highlight invocation) take the historical code
+	 * path unchanged. .phpc detection is purely additive.
+	 */
+	bool is_phpc_file = false;
+	{
+		zend_string *fname = file_handle->opened_path
+			? file_handle->opened_path : file_handle->filename;
+		if (fname && ZSTR_LEN(fname) >= sizeof(".phpc") - 1) {
+			const char *tail = ZSTR_VAL(fname) + ZSTR_LEN(fname) - (sizeof(".phpc") - 1);
+			if (memcmp(tail, ".phpc", sizeof(".phpc") - 1) == 0) {
+				is_phpc_file = true;
+			}
+		}
+	}
+
+	uint32_t phpc_start_lineno = 1;
+	if (is_phpc_file) {
+		unsigned char *p = (unsigned char *)buf;
+		unsigned char *limit = p + size;
+
+		/* Skip a UTF-8 BOM if present. */
+		if (limit - p >= 3 && p[0] == 0xEF && p[1] == 0xBB && p[2] == 0xBF) {
+			p += 3;
+		}
+
+		/* Skip a shebang line in CLI mode. .phpc files can be #!-scripts. */
+		if (CG(skip_shebang) && limit - p >= 2 && p[0] == '#' && p[1] == '!') {
+			while (p < limit && *p != '\n') {
+				p++;
+			}
+			if (p < limit) {
+				p++; /* consume the newline */
+				phpc_start_lineno = 2;
+			}
+		}
+
+		if (p != (unsigned char *)buf) {
+			SCNG(yy_cursor) = p;
+		}
+		BEGIN(ST_IN_SCRIPTING);
+	} else if (CG(skip_shebang)) {
 		BEGIN(SHEBANG);
 	} else {
 		BEGIN(INITIAL);
@@ -585,7 +636,7 @@ ZEND_API zend_result open_file_for_scanning(zend_file_handle *file_handle)
 	SCNG(on_event) = NULL;
 	SCNG(on_event_context) = NULL;
 	RESET_DOC_COMMENT();
-	CG(zend_lineno) = 1;
+	CG(zend_lineno) = phpc_start_lineno;
 	CG(increment_lineno) = 0;
 	return SUCCESS;
 }