diff --git a/src/test/java/de/bonndan/nivio/appuser/AppUserRepositoryTest.java b/src/test/java/de/bonndan/nivio/appuser/AppUserRepositoryTest.java
new file mode 100644
index 000000000..70b926b2a
--- /dev/null
+++ b/src/test/java/de/bonndan/nivio/appuser/AppUserRepositoryTest.java
@@ -0,0 +1,37 @@
+package de.bonndan.nivio.appuser;
+
+import org.junit.jupiter.api.Test;
+import org.junit.runner.RunWith;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.boot.test.autoconfigure.orm.jpa.DataJpaTest;
+import org.springframework.test.context.junit4.SpringRunner;
+
+import java.util.Optional;
+
+import static org.junit.jupiter.api.Assertions.*;
+
+@RunWith(SpringRunner.class)
+@DataJpaTest
+class AppUserRepositoryTest {
+
+    @Autowired
+    private AppUserRepository appUserRepository;
+
+    @Test
+    void findByExternalId() {
+        Optional<AppUser> appUser = Optional.of(new AppUser());
+        appUser.get().setExternalId("100");
+        appUser.get().setAlias("login");
+        appUser.get().setAppUserRole(AppUserRole.USER);
+        appUser.get().setId(1L);
+        appUser.get().setIdp("github");
+
+        appUser.ifPresent(user -> appUserRepository.save(user));
+        final Optional<AppUser> fetchedAppUser = appUserRepository.findByExternalId(appUser.get().getExternalId());
+
+        assertNotNull(appUser);
+        assertNotNull(fetchedAppUser);
+        assertEquals(fetchedAppUser.get().getExternalId(), appUser.get().getExternalId());
+
+    }
+}
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