diff --git a/README.md b/README.md
index bb1e4587..61b93490 100644
--- a/README.md
+++ b/README.md
@@ -47,13 +47,13 @@ If you have at least Docker, the Java JDK and Gradle installed in appropriate ve
     # the following command should return a JSON array with just all customers:
     curl \
         -H 'current-user: mike@hostsharing.net' \
-        http://localhost:8080/api/customer
+        http://localhost:8080/api/customers
 
     # the following command should return a JSON array with just all packages visible for the admin of the customer aab:
     curl \
         -H 'current-user: mike@hostsharing.net' \
         -H 'assumed-roles: customer#aab.admin' \
-        http://localhost:8080/api/package
+        http://localhost:8080/api/packages
 
 The latter `curl` command actually goes through the database server.
 
diff --git a/src/main/java/net/hostsharing/hsadminng/hscustomer/CustomerController.java b/src/main/java/net/hostsharing/hsadminng/hscustomer/CustomerController.java
index b172a068..ffed4130 100644
--- a/src/main/java/net/hostsharing/hsadminng/hscustomer/CustomerController.java
+++ b/src/main/java/net/hostsharing/hsadminng/hscustomer/CustomerController.java
@@ -21,7 +21,7 @@ public class CustomerController {
     private CustomerRepository customerRepository;
 
     @ResponseBody
-    @RequestMapping(value = "/api/customer", method = RequestMethod.GET)
+    @RequestMapping(value = "/api/customers", method = RequestMethod.GET)
     @Transactional
     public List<CustomerEntity> listCustomers(
             @RequestHeader(value = "current-user") String userName,
diff --git a/src/test/java/net/hostsharing/hsadminng/hscustomer/CustomerControllerRestTest.java b/src/test/java/net/hostsharing/hsadminng/hscustomer/CustomerControllerRestTest.java
new file mode 100644
index 00000000..267a1c4a
--- /dev/null
+++ b/src/test/java/net/hostsharing/hsadminng/hscustomer/CustomerControllerRestTest.java
@@ -0,0 +1,49 @@
+package net.hostsharing.hsadminng.hscustomer;
+
+import net.hostsharing.hsadminng.context.Context;
+import org.junit.jupiter.api.Test;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.boot.test.autoconfigure.web.servlet.WebMvcTest;
+import org.springframework.boot.test.mock.mockito.MockBean;
+import org.springframework.http.MediaType;
+import org.springframework.test.web.servlet.MockMvc;
+import org.springframework.test.web.servlet.request.MockMvcRequestBuilders;
+
+import static java.util.Arrays.asList;
+import static java.util.Collections.singletonList;
+import static java.util.UUID.randomUUID;
+import static org.hamcrest.Matchers.hasSize;
+import static org.hamcrest.Matchers.is;
+import static org.mockito.Mockito.*;
+import static org.springframework.test.web.servlet.result.MockMvcResultMatchers.jsonPath;
+import static org.springframework.test.web.servlet.result.MockMvcResultMatchers.status;
+
+@WebMvcTest(CustomerController.class)
+class CustomerControllerRestTest {
+
+    @Autowired
+    MockMvc mockMvc;
+    @MockBean
+    Context contextMock;
+    @MockBean
+    CustomerRepository customerRepositoryMock;
+
+    @Test
+    void apiCustomersWillReturnCustomersFromRepository() throws Exception {
+
+        // given
+        when(customerRepositoryMock.findAll()).thenReturn(asList(TestCustomer.xxx, TestCustomer.yyy));
+
+        // when
+        final var pacs = mockMvc.perform(MockMvcRequestBuilders
+                .get("/api/customers")
+                .header("current-user", "mike@hostsharing.net")
+                .accept(MediaType.APPLICATION_JSON))
+
+            // then
+            .andExpect(status().isOk())
+            .andExpect(jsonPath("$", hasSize(2)))
+            .andExpect(jsonPath("$[0].prefix", is(TestCustomer.xxx.getPrefix())))
+            .andExpect(jsonPath("$[1].reference", is(TestCustomer.yyy.getReference())));
+    }
+}
diff --git a/src/test/java/net/hostsharing/hsadminng/hscustomer/CustomerControllerUnitTest.java b/src/test/java/net/hostsharing/hsadminng/hscustomer/CustomerControllerUnitTest.java
new file mode 100644
index 00000000..71bd0dab
--- /dev/null
+++ b/src/test/java/net/hostsharing/hsadminng/hscustomer/CustomerControllerUnitTest.java
@@ -0,0 +1,55 @@
+package net.hostsharing.hsadminng.hscustomer;
+
+import net.hostsharing.hsadminng.context.Context;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.ExtendWith;
+import org.mockito.InjectMocks;
+import org.mockito.Mock;
+import org.mockito.junit.jupiter.MockitoExtension;
+
+import static java.util.Arrays.asList;
+import static java.util.Collections.singletonList;
+import static org.assertj.core.api.Assertions.assertThat;
+import static org.mockito.Mockito.*;
+
+@ExtendWith(MockitoExtension.class)
+class CustomerControllerUnitTest {
+
+    @Mock
+    Context contextMock;
+    @Mock
+    CustomerRepository customerRepositoryMock;
+
+    @InjectMocks
+    CustomerController customerController;
+
+    @Test
+    void apiCustomersWillReturnCustomersFromRepository() throws Exception {
+
+        // given
+        when(customerRepositoryMock.findAll()).thenReturn(asList(TestCustomer.xxx, TestCustomer.yyy));
+
+        // when
+        final var pacs = customerController.listCustomers("mike@hostsharing.net", null);
+
+        // then
+        assertThat(pacs).hasSize(2);
+        verify(contextMock).setCurrentUser("mike@hostsharing.net");
+        verify(contextMock, never()).assumeRoles(any());
+    }
+
+    @Test
+    void findAllWithAssumedCustomerAdminRole() throws Exception {
+
+        // given
+        when(customerRepositoryMock.findAll()).thenReturn(singletonList(TestCustomer.yyy));
+
+        // when
+        final var pacs = customerController.listCustomers("mike@hostsharing.net", "customer#yyy.admin");
+
+        // then
+        assertThat(pacs).hasSize(1);
+        verify(contextMock).setCurrentUser("mike@hostsharing.net");
+        verify(contextMock).assumeRoles("customer#yyy.admin");
+    }
+}
diff --git a/src/test/java/net/hostsharing/hsadminng/hscustomer/TestCustomer.java b/src/test/java/net/hostsharing/hsadminng/hscustomer/TestCustomer.java
new file mode 100644
index 00000000..ab887848
--- /dev/null
+++ b/src/test/java/net/hostsharing/hsadminng/hscustomer/TestCustomer.java
@@ -0,0 +1,14 @@
+package net.hostsharing.hsadminng.hscustomer;
+
+import static java.util.UUID.randomUUID;
+
+public class TestCustomer {
+
+    static final CustomerEntity xxx = customer("xxx", 10001, "xxx@example.com");
+    static final CustomerEntity yyy = customer("yyy", 10002, "yyy@example.com");
+
+
+    static public CustomerEntity customer(final String prefix, final int reference, final String adminName) {
+        return new CustomerEntity(randomUUID(), prefix, reference, adminName);
+    }
+}