diff --git a/src/test/java/com/slotline/api/ReservationApiTest.java b/src/test/java/com/slotline/api/ReservationApiTest.java
new file mode 100644
index 0000000..d3a40a5
--- /dev/null
+++ b/src/test/java/com/slotline/api/ReservationApiTest.java
@@ -0,0 +1,119 @@
+package com.slotline.api;
+
+import com.fasterxml.jackson.databind.JsonNode;
+import com.fasterxml.jackson.databind.ObjectMapper;
+import com.slotline.reservation.dto.ReservationRequest;
+import com.slotline.resource.dto.ResourceRequest;
+import com.slotline.user.dto.LoginRequest;
+import com.slotline.user.dto.RegisterRequest;
+import org.junit.jupiter.api.Test;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.boot.test.autoconfigure.web.servlet.AutoConfigureMockMvc;
+import org.springframework.boot.test.context.SpringBootTest;
+import org.springframework.http.MediaType;
+import org.springframework.test.web.servlet.MockMvc;
+import org.springframework.test.web.servlet.MvcResult;
+import org.springframework.transaction.annotation.Transactional;
+
+import java.time.Instant;
+
+import static org.springframework.test.web.servlet.request.MockMvcRequestBuilders.get;
+import static org.springframework.test.web.servlet.request.MockMvcRequestBuilders.post;
+import static org.springframework.test.web.servlet.result.MockMvcResultMatchers.jsonPath;
+import static org.springframework.test.web.servlet.result.MockMvcResultMatchers.status;
+
+@SpringBootTest
+@AutoConfigureMockMvc
+@Transactional
+class ReservationApiTest {
+
+    private static final Instant SLOT_START = Instant.parse("2026-09-01T10:00:00Z");
+    private static final Instant SLOT_END = Instant.parse("2026-09-01T11:00:00Z");
+
+    @Autowired
+    private MockMvc mockMvc;
+
+    @Autowired
+    private ObjectMapper objectMapper;
+
+    @Test
+    void happyPathBookingThenConflictThenCancelThenRebook() throws Exception {
+        mockMvc.perform(post("/api/auth/register")
+                        .contentType(MediaType.APPLICATION_JSON)
+                        .content(json(new RegisterRequest("alice", "password123"))))
+                .andExpect(status().isCreated())
+                .andExpect(jsonPath("$.role").value("USER"));
+
+        String userToken = login("alice", "password123");
+        String adminToken = login("admin", "admin12345");
+
+        mockMvc.perform(post("/api/resources")
+                        .header("Authorization", "Bearer " + userToken)
+                        .contentType(MediaType.APPLICATION_JSON)
+                        .content(json(new ResourceRequest("Court 1", "Blocked for USER"))))
+                .andExpect(status().isForbidden());
+
+        MvcResult created = mockMvc.perform(post("/api/resources")
+                        .header("Authorization", "Bearer " + adminToken)
+                        .contentType(MediaType.APPLICATION_JSON)
+                        .content(json(new ResourceRequest("Court 1", "Outdoor tennis court"))))
+                .andExpect(status().isCreated())
+                .andReturn();
+        long resourceId = tree(created).get("id").asLong();
+
+        ReservationRequest slot = new ReservationRequest(resourceId, SLOT_START, SLOT_END);
+
+        mockMvc.perform(post("/api/reservations")
+                        .contentType(MediaType.APPLICATION_JSON)
+                        .content(json(slot)))
+                .andExpect(status().isUnauthorized());
+
+        MvcResult reservation = mockMvc.perform(post("/api/reservations")
+                        .header("Authorization", "Bearer " + userToken)
+                        .contentType(MediaType.APPLICATION_JSON)
+                        .content(json(slot)))
+                .andExpect(status().isCreated())
+                .andExpect(jsonPath("$.status").value("ACTIVE"))
+                .andReturn();
+        long reservationId = tree(reservation).get("id").asLong();
+
+        mockMvc.perform(post("/api/reservations")
+                        .header("Authorization", "Bearer " + userToken)
+                        .contentType(MediaType.APPLICATION_JSON)
+                        .content(json(slot)))
+                .andExpect(status().isConflict());
+
+        mockMvc.perform(post("/api/reservations/" + reservationId + "/cancel")
+                        .header("Authorization", "Bearer " + userToken))
+                .andExpect(status().isOk())
+                .andExpect(jsonPath("$.status").value("CANCELLED"));
+
+        mockMvc.perform(post("/api/reservations")
+                        .header("Authorization", "Bearer " + userToken)
+                        .contentType(MediaType.APPLICATION_JSON)
+                        .content(json(slot)))
+                .andExpect(status().isCreated());
+
+        mockMvc.perform(get("/api/resources/" + resourceId + "/reservations")
+                        .header("Authorization", "Bearer " + userToken))
+                .andExpect(status().isOk())
+                .andExpect(jsonPath("$.length()").value(1));
+    }
+
+    private String login(String username, String password) throws Exception {
+        MvcResult result = mockMvc.perform(post("/api/auth/login")
+                        .contentType(MediaType.APPLICATION_JSON)
+                        .content(json(new LoginRequest(username, password))))
+                .andExpect(status().isOk())
+                .andReturn();
+        return tree(result).get("token").asText();
+    }
+
+    private String json(Object payload) throws Exception {
+        return objectMapper.writeValueAsString(payload);
+    }
+
+    private JsonNode tree(MvcResult result) throws Exception {
+        return objectMapper.readTree(result.getResponse().getContentAsString());
+    }
+}