diff --git a/src/Plugins/Shard.php b/src/Plugins/Shard.php
index 814125f20..610ce8949 100644
--- a/src/Plugins/Shard.php
+++ b/src/Plugins/Shard.php
@@ -193,7 +193,7 @@ private function allTests(array $arguments): array
             '--list-tests',
         ]))->setTimeout(120)->mustRun()->getOutput();
 
-        preg_match_all('/ - (?:P\\\\)?(Tests\\\\[^:]+)::/', $output, $matches);
+        preg_match_all('/ - (?:P\\\\)?([^:]+)::/', $output, $matches);
 
         return array_values(array_unique($matches[1]));
     }
diff --git a/tests-external/Shard/modules/billing/InvoiceTest.php b/tests-external/Shard/modules/billing/InvoiceTest.php
new file mode 100644
index 000000000..4d565ed6d
--- /dev/null
+++ b/tests-external/Shard/modules/billing/InvoiceTest.php
@@ -0,0 +1,5 @@
+<?php
+
+it('creates invoice')->assertTrue(true);
+
+it('sends invoice')->assertTrue(true);
diff --git a/tests-external/Shard/standard/UnitTest.php b/tests-external/Shard/standard/UnitTest.php
new file mode 100644
index 000000000..915336ab3
--- /dev/null
+++ b/tests-external/Shard/standard/UnitTest.php
@@ -0,0 +1,3 @@
+<?php
+
+it('passes')->assertTrue(true);
diff --git a/tests/Plugins/Shard.php b/tests/Plugins/Shard.php
new file mode 100644
index 000000000..bd6ff2048
--- /dev/null
+++ b/tests/Plugins/Shard.php
@@ -0,0 +1,129 @@
+<?php
+
+use Symfony\Component\Process\Process;
+
+$pest = function (string $path, array $extraArgs = []): Process {
+    $process = new Process(
+        ['php', 'bin/pest', $path, ...$extraArgs],
+        dirname(__DIR__, 2),
+    );
+    $process->run();
+
+    return $process;
+};
+
+$shardsPath = dirname(__DIR__).'/.pest/shards.json';
+
+afterAll(function () use ($shardsPath) {
+    if (file_exists($shardsPath)) {
+        unlink($shardsPath);
+    }
+});
+
+test('shard discovers tests in standard directories', function () use ($pest) {
+    $process = $pest('tests/Fixtures/DirectoryWithTests/', ['--list-tests']);
+
+    expect($process->getExitCode())->toBe(0);
+
+    $output = $process->getOutput();
+
+    expect($output)->toContain('ExampleTest::')
+        ->toContain(' - P\Tests\\');
+})->skipOnWindows();
+
+test('shard includes standard directory tests in shard count', function () use ($pest) {
+    $process = $pest('tests/Fixtures/DirectoryWithTests/', ['--shard=1/1']);
+
+    expect($process->getExitCode())->toBe(0);
+
+    $output = $process->getOutput();
+
+    expect($output)->toContain('1 file ran, out of 1');
+})->skipOnWindows();
+
+test('shard distributes standard directory tests across shards', function () use ($pest) {
+    $process1 = $pest('tests/Fixtures/DirectoryWithTests/', ['--shard=1/2']);
+    $process2 = $pest('tests/Fixtures/DirectoryWithTests/', ['--shard=2/2']);
+
+    expect($process1->getExitCode())->toBe(0)
+        ->and($process2->getExitCode())->toBe(0);
+
+    $output1 = $process1->getOutput();
+    $output2 = $process2->getOutput();
+
+    // 1 file total — first shard gets it, second gets 0
+    expect($output1)->toContain('1 file ran, out of 1')
+        ->and($output2)->toContain('0 files ran, out of 1');
+})->skipOnWindows();
+
+test('update-shards records timings for standard directory tests', function () use ($pest, $shardsPath) {
+    $process = $pest('tests/Fixtures/DirectoryWithTests/', ['--update-shards']);
+
+    expect($process->getExitCode())->toBe(0);
+
+    $output = $process->getOutput();
+
+    expect($output)->toContain('shards.json updated with timings for 1 test class');
+
+    expect($shardsPath)->toBeFile();
+    $data = json_decode(file_get_contents($shardsPath), true);
+    $keys = array_keys($data['timings']);
+
+    expect($keys)->each->toStartWith('Tests\\');
+})->skipOnWindows();
+
+test('shard discovers tests in non-standard directories', function () use ($pest) {
+    $process = $pest('tests-external/Shard/', ['--list-tests']);
+
+    expect($process->getExitCode())->toBe(0);
+
+    $output = $process->getOutput();
+
+    // Identifiers must NOT start with Tests\ since fixtures are in tests-external/
+    expect($output)->toContain('InvoiceTest::')
+        ->toContain('UnitTest::')
+        ->not->toContain(' - P\Tests\\');
+})->skipOnWindows();
+
+test('shard includes non-standard directory tests in shard count', function () use ($pest) {
+    $process = $pest('tests-external/Shard/', ['--shard=1/1']);
+
+    expect($process->getExitCode())->toBe(0);
+
+    $output = $process->getOutput();
+
+    // Both test files must be discovered and sharded
+    expect($output)->toContain('2 files ran, out of 2');
+})->skipOnWindows();
+
+test('shard distributes non-standard directory tests across shards', function () use ($pest) {
+    $process1 = $pest('tests-external/Shard/', ['--shard=1/2']);
+    $process2 = $pest('tests-external/Shard/', ['--shard=2/2']);
+
+    expect($process1->getExitCode())->toBe(0)
+        ->and($process2->getExitCode())->toBe(0);
+
+    $output1 = $process1->getOutput();
+    $output2 = $process2->getOutput();
+
+    // Each shard gets 1 file, total is 2
+    expect($output1)->toContain('1 file ran, out of 2')
+        ->and($output2)->toContain('1 file ran, out of 2');
+})->skipOnWindows();
+
+test('update-shards records timings for non-standard directory tests', function () use ($pest, $shardsPath) {
+    $process = $pest('tests-external/Shard/', ['--update-shards']);
+
+    expect($process->getExitCode())->toBe(0);
+
+    $output = $process->getOutput();
+
+    expect($output)->toContain('shards.json updated with timings for 2 test class');
+
+    // Verify the shards.json contains the non-standard identifiers
+    expect($shardsPath)->toBeFile();
+    $data = json_decode(file_get_contents($shardsPath), true);
+    $keys = array_keys($data['timings']);
+
+    expect($keys)->each->not->toStartWith('Tests\\');
+})->skipOnWindows();