diff --git a/README.md b/README.md
index dd65519..917b1b0 100644
--- a/README.md
+++ b/README.md
@@ -14,6 +14,7 @@ This extension specifies types of values passed to:
 * `Assert::stringNotEmpty`
 * `Assert::float`
 * `Assert::numeric`
+* `Assert::integerish`
 * `Assert::boolean`
 * `Assert::scalar`
 * `Assert::object`
diff --git a/src/Type/WebMozartAssert/AssertTypeSpecifyingExtension.php b/src/Type/WebMozartAssert/AssertTypeSpecifyingExtension.php
index 01b64cc..37307a9 100644
--- a/src/Type/WebMozartAssert/AssertTypeSpecifyingExtension.php
+++ b/src/Type/WebMozartAssert/AssertTypeSpecifyingExtension.php
@@ -192,6 +192,24 @@ private static function getExpressionResolvers(): array
 						[$value]
 					);
 				},
+				'integerish' => function (Scope $scope, Arg $value): ?\PhpParser\Node\Expr {
+					return new \PhpParser\Node\Expr\BinaryOp\BooleanOr(
+						new \PhpParser\Node\Expr\BinaryOp\BooleanAnd(
+							new \PhpParser\Node\Expr\FuncCall(
+								new \PhpParser\Node\Name('is_string'),
+								[$value]
+							),
+							new \PhpParser\Node\Expr\FuncCall(
+								new \PhpParser\Node\Name('is_numeric'),
+								[$value]
+							)
+						),
+						new \PhpParser\Node\Expr\FuncCall(
+							new \PhpParser\Node\Name('is_int'),
+							[$value]
+						)
+					);
+				},
 				'numeric' => function (Scope $scope, Arg $value): ?\PhpParser\Node\Expr {
 					return new \PhpParser\Node\Expr\FuncCall(
 						new \PhpParser\Node\Name('is_numeric'),
diff --git a/tests/Type/WebMozartAssert/AssertTypeSpecifyingExtensionTest.php b/tests/Type/WebMozartAssert/AssertTypeSpecifyingExtensionTest.php
index 29cf914..b095fc1 100644
--- a/tests/Type/WebMozartAssert/AssertTypeSpecifyingExtensionTest.php
+++ b/tests/Type/WebMozartAssert/AssertTypeSpecifyingExtensionTest.php
@@ -149,6 +149,10 @@ public function testExtension(): void
 				'Variable $ac is: string',
 				116,
 			],
+			[
+				'Variable $ad is: int|string',
+				119,
+			],
 		]);
 	}
 
diff --git a/tests/Type/WebMozartAssert/data/data.php b/tests/Type/WebMozartAssert/data/data.php
index b6288f5..3ddf4aa 100644
--- a/tests/Type/WebMozartAssert/data/data.php
+++ b/tests/Type/WebMozartAssert/data/data.php
@@ -7,7 +7,7 @@
 class Foo
 {
 
-	public function doFoo($a, $b, array $c, iterable $d, $e, $f, $g, $h, $i, $j, $k, $l, $m, $n, $o, $p, $r, $s, ?int $t, ?int $u, $x, $aa, array $ab, $ac)
+	public function doFoo($a, $b, array $c, iterable $d, $e, $f, $g, $h, $i, $j, $k, $l, $m, $n, $o, $p, $r, $s, ?int $t, ?int $u, $x, $aa, array $ab, $ac, $ad)
 	{
 		$a;
 
@@ -114,6 +114,9 @@ public function doFoo($a, $b, array $c, iterable $d, $e, $f, $g, $h, $i, $j, $k,
 
 		Assert::stringNotEmpty($ac);
 		$ac;
+
+		Assert::integerish($ad);
+		$ad;
 	}
 
 }