diff --git a/e2e/binary/mktemp/BUILD.bazel b/e2e/binary/mktemp/BUILD.bazel
index 9e28d643ec94a3537708f512761f213cf7f2302f..9f5b84a9765554d6cb0f681987b42f4c60c99619 100644
--- a/e2e/binary/mktemp/BUILD.bazel
+++ b/e2e/binary/mktemp/BUILD.bazel
@@ -1,11 +1,33 @@
-load("@bazel_skylib//rules:build_test.bzl", "build_test")
+load("@bazel_skylib//rules:native_binary.bzl", "native_test")
+load("@rules_python_pytest//python_pytest:defs.bzl", "py_pytest_test")
 
-# TODO: write an _actual_ test for `mktemp`
+py_pytest_test(
+    name = "pytest",
+    size = "small",
+    srcs = ["mktemp.py"],
+    data = [
+        "@ape//ape:mktemp",
+    ],
+    deps = [
+        "//binary:pytest",
+    ],
+)
 
-build_test(
-    name = "mktemp",
+native_test(
+    name = "native",
     size = "small",
-    tags = ["stub"],
-    targets = ["@ape//ape:mktemp"],
+    src = "@ape//ape:mktemp",
+    args = [
+        "-u",
+        "XXXXXXXXXXXXX",
+    ],
+)
+
+test_suite(
+    name = "mktemp",
+    tests = [
+        "native",
+        "pytest",
+    ],
     visibility = ["//:__subpackages__"],
 )
diff --git a/e2e/binary/mktemp/mktemp.py b/e2e/binary/mktemp/mktemp.py
new file mode 100644
index 0000000000000000000000000000000000000000..279c04a2d8c1b84fcae012de2ffe54696a9cdaa9
--- /dev/null
+++ b/e2e/binary/mktemp/mktemp.py
@@ -0,0 +1,18 @@
+from __future__ import annotations
+
+from pathlib import Path
+from re import compile
+from subprocess import run
+
+from binary import Tool
+
+
+def test_mktemp_regex(tool: Tool, tmp_path: Path) -> None:
+    binary = tool("mktemp")
+
+    cmd = (binary, f"{tmp_path / 'XXXXXXXXXXXXX.txt'}")
+    run(cmd, check=True, timeout=30)
+    first, *_ = tmp_path.glob("*.txt")
+    random = first.with_suffix("").name
+    regex = compile(r"[a-zA-Z0-9]{13}")
+    assert regex.match(random)