diff --git a/runners/mlcube_singularity/mlcube_singularity/singularity_client.py b/runners/mlcube_singularity/mlcube_singularity/singularity_client.py
index 4f141d4..ea09395 100644
--- a/runners/mlcube_singularity/mlcube_singularity/singularity_client.py
+++ b/runners/mlcube_singularity/mlcube_singularity/singularity_client.py
@@ -104,16 +104,18 @@ def from_env(cls) -> "Client":
     def supports_fakeroot(self) -> bool:
         singularity_35 = (
             self.version.runtime == Runtime.SINGULARITY
-            and self.version >= semver.VersionInfo(major=3, minor=5)
+            and self.version.version >= semver.VersionInfo(major=3, minor=5)
         )
         apptainer = self.version.runtime == Runtime.APPTAINER
         return singularity_35 or apptainer
 
-    def __init__(self, singularity: t.Union[str, t.List]) -> None:
+    def __init__(
+        self, singularity: t.Union[str, t.List], version: t.Optional[Version] = None
+    ) -> None:
         if isinstance(singularity, str):
             singularity = singularity.split(" ")
         self.singularity: t.List[str] = [c.strip() for c in singularity if c.strip()]
-        self.version: t.Optional[Version] = None
+        self.version: t.Optional[Version] = version
         self.init()
         logger.debug(
             "Client.__init__ executable=%s, version=%s", self.singularity, self.version
diff --git a/runners/mlcube_singularity/mlcube_singularity/tests/test_singularity_client.py b/runners/mlcube_singularity/mlcube_singularity/tests/test_singularity_client.py
new file mode 100644
index 0000000..d7c076b
--- /dev/null
+++ b/runners/mlcube_singularity/mlcube_singularity/tests/test_singularity_client.py
@@ -0,0 +1,40 @@
+from unittest import TestCase
+
+import semver
+from mlcube_singularity.singularity_client import Client, Runtime, Version
+
+
+class TestSingularityRunner(TestCase):
+    def test___init__(self) -> None:
+        client = Client(
+            "sudo singularity", Version(Runtime.APPTAINER, semver.VersionInfo(3, 7, 5))
+        )
+        self.assertListEqual(["sudo", "singularity"], client.singularity)
+        self.assertEqual(Runtime.APPTAINER, client.version.runtime)
+        self.assertEqual(3, client.version.version.major)
+        self.assertEqual(7, client.version.version.minor)
+        self.assertEqual(5, client.version.version.patch)
+
+    def test_supports_fakeroot(self) -> None:
+        client = Client(
+            "sudo singularity", Version(Runtime.APPTAINER, semver.VersionInfo(3, 7, 5))
+        )
+        self.assertTrue(client.supports_fakeroot())
+
+        client = Client(
+            "sudo singularity",
+            Version(Runtime.SINGULARITY, semver.VersionInfo(3, 7, 5)),
+        )
+        self.assertTrue(client.supports_fakeroot())
+
+        client = Client(
+            "sudo singularity",
+            Version(Runtime.SINGULARITY, semver.VersionInfo(3, 5, 0)),
+        )
+        self.assertTrue(client.supports_fakeroot())
+
+        client = Client(
+            "sudo singularity",
+            Version(Runtime.SINGULARITY, semver.VersionInfo(3, 4, 9)),
+        )
+        self.assertFalse(client.supports_fakeroot())