backend/src/main/java/org/raddatz/familienarchiv/audit/AuditKind.java

@@ -26,7 +26,16 @@ public enum AuditKind {
     COMMENT_ADDED,
 
     /** Payload: {@code {"commentId": "uuid", "mentionedUserId": "uuid"}} */
-    MENTION_CREATED;
+    MENTION_CREATED,
+
+    /** Payload: {@code {"userId": "uuid", "email": "addr"}} */
+    USER_CREATED,
+
+    /** Payload: {@code {"userId": "uuid", "email": "addr"}} */
+    USER_DELETED,
+
+    /** Payload: {@code {"userId": "uuid", "email": "addr", "addedGroups": ["Admin"], "removedGroups": []}} */
+    GROUP_MEMBERSHIP_CHANGED;
 
     public static final Set<AuditKind> ROLLUP_ELIGIBLE = Set.of(
             TEXT_SAVED, FILE_UPLOADED, ANNOTATION_CREATED,

backend/src/main/java/org/raddatz/familienarchiv/audit/AuditLogQueryRepository.java

@@ -1,5 +1,7 @@
 package org.raddatz.familienarchiv.audit;
 
+import org.springframework.data.domain.Page;
+import org.springframework.data.domain.Pageable;
 import org.springframework.data.jpa.repository.JpaRepository;
 import org.springframework.data.jpa.repository.Query;
 import org.springframework.data.repository.query.Param;
@@ -197,4 +199,6 @@ public interface AuditLogQueryRepository extends JpaRepository<AuditLog, UUID> {
             ORDER BY ranked.document_id, ranked.rn
             """, nativeQuery = true)
     List<ContributorRow> findRecentContributorsForDocuments(@Param("documentIds") List<UUID> documentIds);
+
+    Page<AuditLog> findByKindIn(Collection<AuditKind> kinds, Pageable pageable);
 }

backend/src/main/java/org/raddatz/familienarchiv/audit/AuditLogQueryService.java

@@ -1,11 +1,17 @@
 package org.raddatz.familienarchiv.audit;
 
 import lombok.RequiredArgsConstructor;
+import org.springframework.data.domain.PageRequest;
+import org.springframework.data.domain.Sort;
 import org.springframework.stereotype.Service;
 
 import java.time.OffsetDateTime;
 import java.util.*;
 
+import static org.raddatz.familienarchiv.audit.AuditKind.GROUP_MEMBERSHIP_CHANGED;
+import static org.raddatz.familienarchiv.audit.AuditKind.USER_CREATED;
+import static org.raddatz.familienarchiv.audit.AuditKind.USER_DELETED;
+
 @Service
 @RequiredArgsConstructor
 public class AuditLogQueryService {
@@ -51,6 +57,11 @@ public class AuditLogQueryService {
         return toContributorMap(queryRepository.findRecentContributorsForDocuments(documentIds));
     }
 
+    public List<AuditLog> findRecentUserManagementEvents(int limit) {
+        PageRequest page = PageRequest.of(0, limit, Sort.by("happenedAt").descending());
+        return queryRepository.findByKindIn(Set.of(USER_CREATED, USER_DELETED, GROUP_MEMBERSHIP_CHANGED), page).getContent();
+    }
+
     private Map<UUID, List<ActivityActorDTO>> toContributorMap(List<ContributorRow> rows) {
         Map<UUID, List<ActivityActorDTO>> result = new LinkedHashMap<>();
         for (ContributorRow row : rows) {

backend/src/main/java/org/raddatz/familienarchiv/audit/AuditLogRepository.java

@@ -5,4 +5,5 @@ import org.springframework.data.jpa.repository.JpaRepository;
 import java.util.UUID;
 
 public interface AuditLogRepository extends JpaRepository<AuditLog, UUID> {
+    boolean existsByKind(AuditKind kind);
 }

backend/src/main/java/org/raddatz/familienarchiv/controller/UserController.java

@@ -78,24 +78,31 @@ public class UserController {
 
     @PostMapping("/users")
     @RequirePermission(Permission.ADMIN_USER)
-    public ResponseEntity<AppUser> createUser(@Valid @RequestBody CreateUserRequest request) {
-        return ResponseEntity.ok(userService.createUserOrUpdate(request));
+    public ResponseEntity<AppUser> createUser(Authentication authentication,
+                                              @Valid @RequestBody CreateUserRequest request) {
+        return ResponseEntity.ok(userService.createUserOrUpdate(actorId(authentication), request));
     }
 
     @PutMapping("/users/{id}")
     @RequirePermission(Permission.ADMIN_USER)
-    public ResponseEntity<AppUser> adminUpdateUser(@PathVariable UUID id,
+    public ResponseEntity<AppUser> adminUpdateUser(Authentication authentication,
+                                                    @PathVariable UUID id,
                                                     @RequestBody AdminUpdateUserRequest dto) {
-        AppUser updated = userService.adminUpdateUser(id, dto);
+        AppUser updated = userService.adminUpdateUser(actorId(authentication), id, dto);
         updated.setPassword(null);
         return ResponseEntity.ok(updated);
     }
 
     @DeleteMapping("/users/{id}")
     @RequirePermission(Permission.ADMIN_USER)
-    public ResponseEntity<Void> deleteUser(@PathVariable UUID id) {
-        userService.deleteUser(id);
+    public ResponseEntity<Void> deleteUser(Authentication authentication,
+                                           @PathVariable UUID id) {
+        userService.deleteUser(actorId(authentication), id);
         return ResponseEntity.ok().build();
     }
 
+    private UUID actorId(Authentication auth) {
+        return userService.findByEmail(auth.getName()).getId();
+    }
+
 }

backend/src/main/java/org/raddatz/familienarchiv/service/UserService.java

@@ -3,6 +3,8 @@ package org.raddatz.familienarchiv.service;
 import lombok.RequiredArgsConstructor;
 import lombok.extern.slf4j.Slf4j;
 
+import org.raddatz.familienarchiv.audit.AuditKind;
+import org.raddatz.familienarchiv.audit.AuditService;
 import org.raddatz.familienarchiv.dto.AdminUpdateUserRequest;
 import org.raddatz.familienarchiv.dto.ChangePasswordDTO;
 import org.raddatz.familienarchiv.dto.CreateUserRequest;
@@ -21,10 +23,13 @@ import org.springframework.transaction.annotation.Transactional;
 import java.util.Collection;
 import java.util.HashSet;
 import java.util.List;
+import java.util.Map;
 import java.util.Optional;
 import java.util.Set;
 import java.util.UUID;
 
+import static java.util.stream.Collectors.toSet;
+
 @Service
 @RequiredArgsConstructor
 @Slf4j
@@ -33,9 +38,10 @@ public class UserService {
     private final AppUserRepository userRepository;
     private final UserGroupRepository groupRepository;
     private final PasswordEncoder passwordEncoder;
+    private final AuditService auditService;
 
     @Transactional
-    public AppUser createUserOrUpdate(CreateUserRequest request) {
+    public AppUser createUserOrUpdate(UUID actorId, CreateUserRequest request) {
         log.info("Creating or updating user: {}", request.getEmail());
 
         Set<UserGroup> groups = new HashSet<>();
@@ -45,10 +51,12 @@ public class UserService {
 
         Optional<AppUser> existingUser = userRepository.findByEmail(request.getEmail());
         AppUser user;
+        boolean isNew;
 
         if (existingUser.isPresent()) {
             log.info("User exists, updating: {}", request.getEmail());
             user = existingUser.get().updateFromRequest(request, passwordEncoder, groups);
+            isNew = false;
         } else {
             log.info("Creating new user: {}", request.getEmail());
             user = AppUser.builder()
@@ -61,8 +69,42 @@ public class UserService {
                     .contact(request.getContact())
                     .enabled(true)
                     .build();
+            isNew = true;
         }
 
+        AppUser saved = userRepository.save(user);
+        if (isNew) {
+            auditService.logAfterCommit(AuditKind.USER_CREATED, actorId, null,
+                    Map.of("userId", saved.getId().toString(), "email", saved.getEmail()));
+        }
+        return saved;
+    }
+
+    @Transactional
+    public AppUser createUserForBootstrap(CreateUserRequest request) {
+        log.info("Bootstrap user creation (no audit): {}", request.getEmail());
+
+        Set<UserGroup> groups = new HashSet<>();
+        if (request.getGroupIds() != null && !request.getGroupIds().isEmpty()) {
+            groups.addAll(groupRepository.findAllById(request.getGroupIds()));
+        }
+
+        Optional<AppUser> existingUser = userRepository.findByEmail(request.getEmail());
+        if (existingUser.isPresent()) {
+            AppUser updated = existingUser.get().updateFromRequest(request, passwordEncoder, groups);
+            return userRepository.save(updated);
+        }
+
+        AppUser user = AppUser.builder()
+                .email(request.getEmail())
+                .password(passwordEncoder.encode(request.getInitialPassword()))
+                .groups(groups)
+                .firstName(request.getFirstName())
+                .lastName(request.getLastName())
+                .birthDate(request.getBirthDate())
+                .contact(request.getContact())
+                .enabled(true)
+                .build();
         return userRepository.save(user);
     }
 
@@ -94,10 +136,13 @@ public class UserService {
     }
 
     @Transactional
-    public void deleteUser(UUID userId) {
+    public void deleteUser(UUID actorId, UUID userId) {
         AppUser user = userRepository.findById(userId)
                 .orElseThrow(() -> DomainException.notFound(ErrorCode.USER_NOT_FOUND, "No user found for id: " + userId));
+        String email = user.getEmail();
         userRepository.delete(user);
+        auditService.logAfterCommit(AuditKind.USER_DELETED, actorId, null,
+                Map.of("userId", userId.toString(), "email", email));
     }
 
     public AppUser getById(UUID id) {
@@ -141,7 +186,7 @@ public class UserService {
     }
 
     @Transactional
-    public AppUser adminUpdateUser(UUID id, AdminUpdateUserRequest dto) {
+    public AppUser adminUpdateUser(UUID actorId, UUID id, AdminUpdateUserRequest dto) {
         AppUser user = getById(id);
 
         if (dto.getEmail() != null && !dto.getEmail().isBlank()) {
@@ -166,13 +211,27 @@ public class UserService {
         }
 
         if (dto.getGroupIds() != null) {
-            Set<UserGroup> groups = new HashSet<>(groupRepository.findAllById(dto.getGroupIds()));
-            user.setGroups(groups);
+            Set<UserGroup> before = new HashSet<>(user.getGroups());
+            Set<UserGroup> after = new HashSet<>(groupRepository.findAllById(dto.getGroupIds()));
+            user.setGroups(after);
+            groupChangePayload(before, after, id, user.getEmail())
+                    .ifPresent(payload -> auditService.logAfterCommit(AuditKind.GROUP_MEMBERSHIP_CHANGED, actorId, null, payload));
         }
 
         return userRepository.save(user);
     }
 
+    private Optional<Map<String, Object>> groupChangePayload(
+            Set<UserGroup> before, Set<UserGroup> after, UUID userId, String email) {
+        Set<UUID> beforeIds = before.stream().map(UserGroup::getId).collect(toSet());
+        Set<UUID> afterIds = after.stream().map(UserGroup::getId).collect(toSet());
+        if (beforeIds.equals(afterIds)) return Optional.empty();
+        List<String> added = after.stream().filter(g -> !beforeIds.contains(g.getId())).map(UserGroup::getName).toList();
+        List<String> removed = before.stream().filter(g -> !afterIds.contains(g.getId())).map(UserGroup::getName).toList();
+        return Optional.of(Map.of("userId", userId.toString(), "email", email,
+                "addedGroups", added, "removedGroups", removed));
+    }
+
     @Transactional
     public void changePassword(UUID userId, ChangePasswordDTO dto) {
         AppUser user = getById(userId);

backend/src/test/java/org/raddatz/familienarchiv/audit/AuditLogQueryServiceTest.java

@@ -6,12 +6,19 @@ import org.mockito.InjectMocks;
 import org.mockito.Mock;
 import org.mockito.junit.jupiter.MockitoExtension;
 
+import org.raddatz.familienarchiv.model.AppUser;
+import org.springframework.data.domain.PageImpl;
+import org.springframework.data.domain.Pageable;
+
+import java.util.Collection;
 import java.util.List;
 import java.util.Set;
 import java.util.UUID;
 
 import static org.assertj.core.api.Assertions.assertThat;
+import static org.mockito.ArgumentMatchers.any;
 import static org.mockito.ArgumentMatchers.anyCollection;
+import static org.mockito.ArgumentMatchers.argThat;
 import static org.mockito.ArgumentMatchers.eq;
 import static org.mockito.Mockito.verify;
 import static org.mockito.Mockito.when;
@@ -47,4 +54,21 @@ class AuditLogQueryServiceTest {
         verify(queryRepository).findRolledUpActivityFeed(eq(userId.toString()), eq(10),
                 eq(AuditKind.ROLLUP_ELIGIBLE.stream().map(Enum::name).toList()));
     }
+
+    @Test
+    void findRecentUserManagementEvents_delegatesToRepositoryWithAllThreeKinds() {
+        AuditLog entry = AuditLog.builder().id(UUID.randomUUID()).kind(AuditKind.USER_CREATED).build();
+        when(queryRepository.findByKindIn(anyCollection(), any(Pageable.class)))
+                .thenReturn(new PageImpl<>(List.of(entry)));
+
+        List<AuditLog> result = auditLogQueryService.findRecentUserManagementEvents(5);
+
+        assertThat(result).containsExactly(entry);
+        verify(queryRepository).findByKindIn(
+                argThat((Collection<AuditKind> kinds) ->
+                        kinds.contains(AuditKind.USER_CREATED) &&
+                        kinds.contains(AuditKind.USER_DELETED) &&
+                        kinds.contains(AuditKind.GROUP_MEMBERSHIP_CHANGED)),
+                any(Pageable.class));
+    }
 }

backend/src/test/java/org/raddatz/familienarchiv/audit/UserManagementAuditIntegrationTest.java

@@ -0,0 +1,122 @@
+package org.raddatz.familienarchiv.audit;
+
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
+import org.raddatz.familienarchiv.PostgresContainerConfig;
+import org.raddatz.familienarchiv.dto.AdminUpdateUserRequest;
+import org.raddatz.familienarchiv.dto.CreateUserRequest;
+import org.raddatz.familienarchiv.dto.GroupDTO;
+import org.raddatz.familienarchiv.model.AppUser;
+import org.raddatz.familienarchiv.model.UserGroup;
+import org.raddatz.familienarchiv.repository.AppUserRepository;
+import org.raddatz.familienarchiv.service.UserService;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.boot.test.context.SpringBootTest;
+import org.springframework.context.annotation.Import;
+import org.springframework.test.context.ActiveProfiles;
+import org.springframework.test.context.bean.override.mockito.MockitoBean;
+import org.springframework.transaction.support.TransactionTemplate;
+import software.amazon.awssdk.services.s3.S3Client;
+
+import java.util.List;
+import java.util.Set;
+import java.util.UUID;
+
+import static java.util.concurrent.TimeUnit.SECONDS;
+import static org.assertj.core.api.Assertions.assertThat;
+import static org.awaitility.Awaitility.await;
+
+@SpringBootTest(webEnvironment = SpringBootTest.WebEnvironment.NONE)
+@ActiveProfiles("test")
+@Import(PostgresContainerConfig.class)
+class UserManagementAuditIntegrationTest {
+
+    @MockitoBean S3Client s3Client;
+    @Autowired UserService userService;
+    @Autowired AppUserRepository userRepository;
+    @Autowired AuditLogRepository auditLogRepository;
+    @Autowired AuditLogQueryService auditLogQueryService;
+    @Autowired TransactionTemplate transactionTemplate;
+
+    @BeforeEach
+    void clearAuditLog() {
+        transactionTemplate.execute(status -> { auditLogRepository.deleteAll(); return null; });
+    }
+
+    @Test
+    void createAndDeleteUser_producesOrderedAuditEntries() {
+        // Bootstrap actor with no audit event — clean slate guaranteed by @BeforeEach
+        CreateUserRequest adminReq = new CreateUserRequest();
+        adminReq.setEmail("admin@test.example.com");
+        adminReq.setInitialPassword("admin-secret");
+        AppUser actor = transactionTemplate.execute(status -> userService.createUserForBootstrap(adminReq));
+        UUID actorId = actor.getId();
+
+        // Create the target user — should emit USER_CREATED
+        CreateUserRequest req = new CreateUserRequest();
+        req.setEmail("audit-test@example.com");
+        req.setInitialPassword("secret");
+        transactionTemplate.execute(status -> {
+            userService.createUserOrUpdate(actorId, req);
+            return null;
+        });
+        await().atMost(10, SECONDS).until(() -> auditLogRepository.existsByKind(AuditKind.USER_CREATED));
+
+        // Delete the target user — should emit USER_DELETED
+        AppUser created = userRepository.findByEmail("audit-test@example.com").orElseThrow();
+        transactionTemplate.execute(status -> {
+            userService.deleteUser(actorId, created.getId());
+            return null;
+        });
+        await().atMost(10, SECONDS).until(() -> auditLogRepository.existsByKind(AuditKind.USER_DELETED));
+
+        List<AuditLog> events = auditLogQueryService.findRecentUserManagementEvents(10);
+        assertThat(events).hasSize(2);
+        assertThat(events.get(0).getKind()).isEqualTo(AuditKind.USER_DELETED);
+        assertThat(events.get(1).getKind()).isEqualTo(AuditKind.USER_CREATED);
+    }
+
+    @Test
+    void updateUserGroups_producesGroupMembershipChangedEvent() {
+        GroupDTO groupADto = new GroupDTO(); groupADto.setName("Viewers"); groupADto.setPermissions(Set.of("READ_ALL"));
+        GroupDTO groupBDto = new GroupDTO(); groupBDto.setName("Editors"); groupBDto.setPermissions(Set.of("WRITE_ALL"));
+        UserGroup gA = transactionTemplate.execute(status -> userService.createGroup(groupADto));
+        UserGroup gB = transactionTemplate.execute(status -> userService.createGroup(groupBDto));
+
+        // Bootstrap actor with no audit event — clean slate guaranteed by @BeforeEach
+        CreateUserRequest actorReq = new CreateUserRequest();
+        actorReq.setEmail("actor-group-test@test.example.com");
+        actorReq.setInitialPassword("secret");
+        AppUser actor = transactionTemplate.execute(status -> userService.createUserForBootstrap(actorReq));
+
+        // Create target user pre-assigned to gA — emits USER_CREATED
+        CreateUserRequest targetReq = new CreateUserRequest();
+        targetReq.setEmail("target-group-test@test.example.com");
+        targetReq.setInitialPassword("secret");
+        targetReq.setGroupIds(List.of(gA.getId()));
+        transactionTemplate.execute(status -> userService.createUserOrUpdate(actor.getId(), targetReq));
+        await().atMost(10, SECONDS).until(() -> auditLogRepository.existsByKind(AuditKind.USER_CREATED));
+        transactionTemplate.execute(status -> { auditLogRepository.deleteAll(); return null; });
+
+        AppUser target = userRepository.findByEmail("target-group-test@test.example.com").orElseThrow();
+
+        // Change groups: Viewers → Editors
+        AdminUpdateUserRequest dto = new AdminUpdateUserRequest();
+        dto.setGroupIds(List.of(gB.getId()));
+        transactionTemplate.execute(status -> userService.adminUpdateUser(actor.getId(), target.getId(), dto));
+
+        await().atMost(10, SECONDS).until(() -> auditLogRepository.existsByKind(AuditKind.GROUP_MEMBERSHIP_CHANGED));
+
+        List<AuditLog> events = auditLogQueryService.findRecentUserManagementEvents(10);
+        assertThat(events).hasSize(1);
+        AuditLog event = events.get(0);
+        assertThat(event.getKind()).isEqualTo(AuditKind.GROUP_MEMBERSHIP_CHANGED);
+        assertThat(event.getPayload()).containsEntry("email", "target-group-test@test.example.com");
+        @SuppressWarnings("unchecked")
+        List<String> added = (List<String>) event.getPayload().get("addedGroups");
+        @SuppressWarnings("unchecked")
+        List<String> removed = (List<String>) event.getPayload().get("removedGroups");
+        assertThat(added).containsExactlyInAnyOrder("Editors");
+        assertThat(removed).containsExactlyInAnyOrder("Viewers");
+    }
+}

backend/src/test/java/org/raddatz/familienarchiv/controller/UserControllerTest.java

@@ -18,8 +18,10 @@ import java.util.UUID;
 
 import static org.mockito.ArgumentMatchers.any;
 import static org.mockito.Mockito.when;
+import static org.springframework.test.web.servlet.request.MockMvcRequestBuilders.delete;
 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.request.MockMvcRequestBuilders.put;
 import static org.springframework.test.web.servlet.result.MockMvcResultMatchers.jsonPath;
 import static org.springframework.test.web.servlet.result.MockMvcResultMatchers.status;
 
@@ -104,4 +106,55 @@ class UserControllerTest {
                         .content("{\"email\":\"\",\"initialPassword\":\"secret123\"}"))
                 .andExpect(status().isBadRequest());
     }
+
+    // ─── permission enforcement ───────────────────────────────────────────────
+
+    @Test
+    @WithMockUser(username = "reader@example.com")
+    void createUser_returns403_whenCallerLacksAdminUserPermission() throws Exception {
+        mockMvc.perform(post("/api/users")
+                        .contentType(org.springframework.http.MediaType.APPLICATION_JSON)
+                        .content("{\"email\":\"x@x.com\",\"initialPassword\":\"secret123\"}"))
+                .andExpect(status().isForbidden());
+    }
+
+    @Test
+    @WithMockUser(username = "reader@example.com")
+    void adminUpdateUser_returns403_whenCallerLacksAdminUserPermission() throws Exception {
+        mockMvc.perform(put("/api/users/" + UUID.randomUUID())
+                        .contentType(org.springframework.http.MediaType.APPLICATION_JSON)
+                        .content("{}"))
+                .andExpect(status().isForbidden());
+    }
+
+    @Test
+    @WithMockUser(username = "reader@example.com")
+    void deleteUser_returns403_whenCallerLacksAdminUserPermission() throws Exception {
+        mockMvc.perform(delete("/api/users/" + UUID.randomUUID()))
+                .andExpect(status().isForbidden());
+    }
+
+    // ─── unauthenticated access ───────────────────────────────────────────────
+
+    @Test
+    void createUser_returns401_whenUnauthenticated() throws Exception {
+        mockMvc.perform(post("/api/users")
+                        .contentType(org.springframework.http.MediaType.APPLICATION_JSON)
+                        .content("{\"email\":\"x@x.com\",\"initialPassword\":\"secret123\"}"))
+                .andExpect(status().isUnauthorized());
+    }
+
+    @Test
+    void adminUpdateUser_returns401_whenUnauthenticated() throws Exception {
+        mockMvc.perform(put("/api/users/" + UUID.randomUUID())
+                        .contentType(org.springframework.http.MediaType.APPLICATION_JSON)
+                        .content("{}"))
+                .andExpect(status().isUnauthorized());
+    }
+
+    @Test
+    void deleteUser_returns401_whenUnauthenticated() throws Exception {
+        mockMvc.perform(delete("/api/users/" + UUID.randomUUID()))
+                .andExpect(status().isUnauthorized());
+    }
 }

backend/src/test/java/org/raddatz/familienarchiv/service/UserServiceTest.java

@@ -2,9 +2,12 @@ package org.raddatz.familienarchiv.service;
 
 import org.junit.jupiter.api.Test;
 import org.junit.jupiter.api.extension.ExtendWith;
+import org.mockito.ArgumentCaptor;
 import org.mockito.InjectMocks;
 import org.mockito.Mock;
 import org.mockito.junit.jupiter.MockitoExtension;
+import org.raddatz.familienarchiv.audit.AuditKind;
+import org.raddatz.familienarchiv.audit.AuditService;
 import org.raddatz.familienarchiv.dto.AdminUpdateUserRequest;
 import org.raddatz.familienarchiv.dto.ChangePasswordDTO;
 import org.raddatz.familienarchiv.dto.CreateUserRequest;
@@ -34,6 +37,7 @@ class UserServiceTest {
     @Mock AppUserRepository userRepository;
     @Mock UserGroupRepository groupRepository;
     @Mock PasswordEncoder passwordEncoder;
+    @Mock AuditService auditService;
     @InjectMocks UserService userService;
 
     // ─── findByEmail ──────────────────────────────────────────────────────────
@@ -61,7 +65,7 @@ class UserServiceTest {
         UUID id = UUID.randomUUID();
         when(userRepository.findById(id)).thenReturn(Optional.empty());
 
-        assertThatThrownBy(() -> userService.deleteUser(id))
+        assertThatThrownBy(() -> userService.deleteUser(UUID.randomUUID(), id))
                 .isInstanceOf(DomainException.class);
     }
 
@@ -71,7 +75,7 @@ class UserServiceTest {
         AppUser user = AppUser.builder().id(id).email("gast@example.com").build();
         when(userRepository.findById(id)).thenReturn(Optional.of(user));
 
-        userService.deleteUser(id);
+        userService.deleteUser(UUID.randomUUID(), id);
 
         verify(userRepository).delete(user);
     }
@@ -90,7 +94,7 @@ class UserServiceTest {
         AppUser saved = AppUser.builder().id(UUID.randomUUID()).email("new@example.com").build();
         when(userRepository.save(any())).thenReturn(saved);
 
-        AppUser result = userService.createUserOrUpdate(req);
+        AppUser result = userService.createUserOrUpdate(UUID.randomUUID(), req);
 
         assertThat(result).isEqualTo(saved);
         verify(userRepository).save(any());
@@ -108,7 +112,7 @@ class UserServiceTest {
         when(passwordEncoder.encode(any())).thenReturn("encoded");
         when(userRepository.save(any())).thenReturn(existing);
 
-        userService.createUserOrUpdate(req);
+        userService.createUserOrUpdate(UUID.randomUUID(), req);
 
         verify(userRepository, times(1)).save(existing);
     }
@@ -229,7 +233,7 @@ class UserServiceTest {
         AdminUpdateUserRequest dto = new AdminUpdateUserRequest();
         dto.setFirstName("Ada"); dto.setLastName("Lovelace");
 
-        AppUser result = userService.adminUpdateUser(id, dto);
+        AppUser result = userService.adminUpdateUser(UUID.randomUUID(), id, dto);
 
         assertThat(result.getFirstName()).isEqualTo("Ada");
         assertThat(result.getLastName()).isEqualTo("Lovelace");
@@ -246,7 +250,7 @@ class UserServiceTest {
         AdminUpdateUserRequest dto = new AdminUpdateUserRequest();
         dto.setFirstName("Ada");
 
-        AppUser result = userService.adminUpdateUser(id, dto);
+        AppUser result = userService.adminUpdateUser(UUID.randomUUID(), id, dto);
 
         assertThat(result.getGroups()).containsExactly(adminGroup);
     }
@@ -264,7 +268,7 @@ class UserServiceTest {
         AdminUpdateUserRequest dto = new AdminUpdateUserRequest();
         dto.setGroupIds(List.of(newGroup.getId()));
 
-        AppUser result = userService.adminUpdateUser(id, dto);
+        AppUser result = userService.adminUpdateUser(UUID.randomUUID(), id, dto);
 
         assertThat(result.getGroups()).containsExactly(newGroup);
     }
@@ -281,7 +285,7 @@ class UserServiceTest {
         AdminUpdateUserRequest dto = new AdminUpdateUserRequest();
         dto.setGroupIds(List.of());
 
-        AppUser result = userService.adminUpdateUser(id, dto);
+        AppUser result = userService.adminUpdateUser(UUID.randomUUID(), id, dto);
 
         assertThat(result.getGroups()).isEmpty();
     }
@@ -313,7 +317,7 @@ class UserServiceTest {
         AppUser saved = AppUser.builder().id(UUID.randomUUID()).email("u@example.com").build();
         when(userRepository.save(any())).thenReturn(saved);
 
-        AppUser result = userService.createUserOrUpdate(req);
+        AppUser result = userService.createUserOrUpdate(UUID.randomUUID(), req);
 
         assertThat(result).isEqualTo(saved);
         verify(groupRepository).findAllById(List.of(group.getId()));
@@ -378,7 +382,7 @@ class UserServiceTest {
         AdminUpdateUserRequest dto = new AdminUpdateUserRequest();
         dto.setNewPassword("newSecret");
 
-        AppUser result = userService.adminUpdateUser(id, dto);
+        AppUser result = userService.adminUpdateUser(UUID.randomUUID(), id, dto);
 
         assertThat(result.getPassword()).isEqualTo("newHashed");
     }
@@ -393,7 +397,7 @@ class UserServiceTest {
         AdminUpdateUserRequest dto = new AdminUpdateUserRequest();
         dto.setNewPassword("  ");
 
-        AppUser result = userService.adminUpdateUser(id, dto);
+        AppUser result = userService.adminUpdateUser(UUID.randomUUID(), id, dto);
 
         assertThat(result.getPassword()).isEqualTo("original");
         verify(passwordEncoder, never()).encode(any());
@@ -408,7 +412,7 @@ class UserServiceTest {
         AdminUpdateUserRequest dto = new AdminUpdateUserRequest();
         dto.setEmail("   ");
 
-        assertThatThrownBy(() -> userService.adminUpdateUser(id, dto))
+        assertThatThrownBy(() -> userService.adminUpdateUser(UUID.randomUUID(), id, dto))
                 .isInstanceOf(DomainException.class)
                 .hasMessageContaining("blank");
     }
@@ -425,7 +429,7 @@ class UserServiceTest {
         AdminUpdateUserRequest dto = new AdminUpdateUserRequest();
         dto.setEmail("taken@example.com");
 
-        assertThatThrownBy(() -> userService.adminUpdateUser(id, dto))
+        assertThatThrownBy(() -> userService.adminUpdateUser(UUID.randomUUID(), id, dto))
                 .isInstanceOf(DomainException.class)
                 .hasMessageContaining("E-Mail");
     }
@@ -497,7 +501,7 @@ class UserServiceTest {
         AppUser saved = AppUser.builder().id(UUID.randomUUID()).email("u@example.com").build();
         when(userRepository.save(any())).thenReturn(saved);
 
-        userService.createUserOrUpdate(req);
+        userService.createUserOrUpdate(UUID.randomUUID(), req);
 
         verify(groupRepository, never()).findAllById(any());
     }
@@ -561,7 +565,7 @@ class UserServiceTest {
         AdminUpdateUserRequest dto = new AdminUpdateUserRequest();
         dto.setContact(null);
 
-        AppUser result = userService.adminUpdateUser(id, dto);
+        AppUser result = userService.adminUpdateUser(UUID.randomUUID(), id, dto);
 
         assertThat(result.getContact()).isNull();
     }
@@ -576,7 +580,7 @@ class UserServiceTest {
         AdminUpdateUserRequest dto = new AdminUpdateUserRequest();
         dto.setContact("   ");
 
-        AppUser result = userService.adminUpdateUser(id, dto);
+        AppUser result = userService.adminUpdateUser(UUID.randomUUID(), id, dto);
 
         assertThat(result.getContact()).isNull();
     }
@@ -591,7 +595,7 @@ class UserServiceTest {
         AdminUpdateUserRequest dto = new AdminUpdateUserRequest();
         dto.setContact("  phone: 555  ");
 
-        AppUser result = userService.adminUpdateUser(id, dto);
+        AppUser result = userService.adminUpdateUser(UUID.randomUUID(), id, dto);
 
         assertThat(result.getContact()).isEqualTo("phone: 555");
     }
@@ -606,7 +610,7 @@ class UserServiceTest {
         AdminUpdateUserRequest dto = new AdminUpdateUserRequest();
         dto.setEmail(null);
 
-        AppUser result = userService.adminUpdateUser(id, dto);
+        AppUser result = userService.adminUpdateUser(UUID.randomUUID(), id, dto);
 
         assertThat(result.getEmail()).isEqualTo("keep@example.com");
     }
@@ -622,7 +626,7 @@ class UserServiceTest {
         AdminUpdateUserRequest dto = new AdminUpdateUserRequest();
         dto.setEmail("me@example.com");
 
-        AppUser result = userService.adminUpdateUser(id, dto);
+        AppUser result = userService.adminUpdateUser(UUID.randomUUID(), id, dto);
         assertThat(result.getEmail()).isEqualTo("me@example.com");
     }
 
@@ -640,7 +644,7 @@ class UserServiceTest {
         AppUser saved = AppUser.builder().id(UUID.randomUUID()).email("ng@example.com").build();
         when(userRepository.save(any())).thenReturn(saved);
 
-        userService.createUserOrUpdate(req);
+        userService.createUserOrUpdate(UUID.randomUUID(), req);
 
         verify(groupRepository, never()).findAllById(any());
     }
@@ -699,6 +703,160 @@ class UserServiceTest {
         assertThat(result).containsExactly(g);
     }
 
+    // ─── audit: GROUP_MEMBERSHIP_CHANGED ─────────────────────────────────────
+
+    @Test
+    void adminUpdateUser_logsGroupMembershipChanged_whenGroupSetChanges() {
+        UUID actorId = UUID.randomUUID();
+        UUID userId = UUID.randomUUID();
+        UserGroup oldGroup = UserGroup.builder().id(UUID.randomUUID()).name("Viewers").permissions(Set.of("READ_ALL")).build();
+        UserGroup newGroup = UserGroup.builder().id(UUID.randomUUID()).name("Editors").permissions(Set.of("WRITE_ALL")).build();
+        AppUser user = AppUser.builder().id(userId).email("u@example.com").groups(Set.of(oldGroup)).build();
+        when(userRepository.findById(userId)).thenReturn(Optional.of(user));
+        when(groupRepository.findAllById(List.of(newGroup.getId()))).thenReturn(List.of(newGroup));
+        when(userRepository.save(any())).thenAnswer(inv -> inv.getArgument(0));
+
+        AdminUpdateUserRequest dto = new AdminUpdateUserRequest();
+        dto.setGroupIds(List.of(newGroup.getId()));
+
+        userService.adminUpdateUser(actorId, userId, dto);
+
+        @SuppressWarnings("unchecked")
+        ArgumentCaptor<java.util.Map<String, Object>> payloadCaptor = ArgumentCaptor.forClass(java.util.Map.class);
+        verify(auditService).logAfterCommit(
+                org.mockito.ArgumentMatchers.eq(AuditKind.GROUP_MEMBERSHIP_CHANGED),
+                org.mockito.ArgumentMatchers.eq(actorId),
+                org.mockito.ArgumentMatchers.isNull(),
+                payloadCaptor.capture());
+        java.util.Map<String, Object> payload = payloadCaptor.getValue();
+        assertThat(payload).containsEntry("email", "u@example.com");
+        assertThat((java.util.List<String>) payload.get("addedGroups")).containsExactly("Editors");
+        assertThat((java.util.List<String>) payload.get("removedGroups")).containsExactly("Viewers");
+    }
+
+    @Test
+    void adminUpdateUser_doesNotLogGroupMembershipChanged_whenGroupsUnchanged() {
+        UUID actorId = UUID.randomUUID();
+        UUID userId = UUID.randomUUID();
+        UserGroup group = UserGroup.builder().id(UUID.randomUUID()).name("Admins").build();
+        AppUser user = AppUser.builder().id(userId).email("u@example.com").groups(Set.of(group)).build();
+        when(userRepository.findById(userId)).thenReturn(Optional.of(user));
+        when(groupRepository.findAllById(List.of(group.getId()))).thenReturn(List.of(group));
+        when(userRepository.save(any())).thenAnswer(inv -> inv.getArgument(0));
+
+        AdminUpdateUserRequest dto = new AdminUpdateUserRequest();
+        dto.setGroupIds(List.of(group.getId()));
+
+        userService.adminUpdateUser(actorId, userId, dto);
+
+        verify(auditService, never()).logAfterCommit(any(), any(), any(), any());
+    }
+
+    @Test
+    void adminUpdateUser_doesNotLogGroupMembershipChanged_whenGroupIdsIsNull() {
+        UUID actorId = UUID.randomUUID();
+        UUID userId = UUID.randomUUID();
+        UserGroup group = UserGroup.builder().id(UUID.randomUUID()).name("Admins").build();
+        AppUser user = AppUser.builder().id(userId).email("u@example.com").groups(Set.of(group)).build();
+        when(userRepository.findById(userId)).thenReturn(Optional.of(user));
+        when(userRepository.save(any())).thenAnswer(inv -> inv.getArgument(0));
+
+        AdminUpdateUserRequest dto = new AdminUpdateUserRequest();
+        // groupIds not set → null
+
+        userService.adminUpdateUser(actorId, userId, dto);
+
+        verify(auditService, never()).logAfterCommit(any(), any(), any(), any());
+    }
+
+    // ─── audit: USER_DELETED ──────────────────────────────────────────────────
+
+    @Test
+    void deleteUser_logsUserDeleted_withEmailInPayload() {
+        UUID actorId = UUID.randomUUID();
+        UUID userId = UUID.randomUUID();
+        AppUser user = AppUser.builder().id(userId).email("gone@example.com").build();
+        when(userRepository.findById(userId)).thenReturn(Optional.of(user));
+
+        userService.deleteUser(actorId, userId);
+
+        @SuppressWarnings("unchecked")
+        ArgumentCaptor<java.util.Map<String, Object>> payloadCaptor = ArgumentCaptor.forClass(java.util.Map.class);
+        verify(auditService).logAfterCommit(
+                org.mockito.ArgumentMatchers.eq(AuditKind.USER_DELETED),
+                org.mockito.ArgumentMatchers.eq(actorId),
+                org.mockito.ArgumentMatchers.isNull(),
+                payloadCaptor.capture());
+        assertThat(payloadCaptor.getValue()).containsEntry("email", "gone@example.com");
+        assertThat(payloadCaptor.getValue()).containsKey("userId");
+    }
+
+    // ─── audit: USER_CREATED ──────────────────────────────────────────────────
+
+    @Test
+    void createUserOrUpdate_logsUserCreated_whenUserIsNew() {
+        UUID actorId = UUID.randomUUID();
+        CreateUserRequest req = new CreateUserRequest();
+        req.setEmail("new@example.com");
+        req.setInitialPassword("secret");
+        req.setGroupIds(List.of());
+
+        when(userRepository.findByEmail("new@example.com")).thenReturn(Optional.empty());
+        when(passwordEncoder.encode("secret")).thenReturn("encoded");
+        AppUser saved = AppUser.builder().id(UUID.randomUUID()).email("new@example.com").build();
+        when(userRepository.save(any())).thenReturn(saved);
+
+        userService.createUserOrUpdate(actorId, req);
+
+        @SuppressWarnings("unchecked")
+        ArgumentCaptor<java.util.Map<String, Object>> payloadCaptor = ArgumentCaptor.forClass(java.util.Map.class);
+        verify(auditService).logAfterCommit(
+                org.mockito.ArgumentMatchers.eq(AuditKind.USER_CREATED),
+                org.mockito.ArgumentMatchers.eq(actorId),
+                org.mockito.ArgumentMatchers.isNull(),
+                payloadCaptor.capture());
+        assertThat(payloadCaptor.getValue()).containsKey("userId");
+        assertThat(payloadCaptor.getValue()).containsEntry("email", "new@example.com");
+    }
+
+    @Test
+    void createUserOrUpdate_doesNotLogUserCreated_whenUserAlreadyExists() {
+        UUID actorId = UUID.randomUUID();
+        CreateUserRequest req = new CreateUserRequest();
+        req.setEmail("existing@example.com");
+        req.setInitialPassword("pass");
+        req.setGroupIds(List.of());
+
+        AppUser existing = AppUser.builder().id(UUID.randomUUID()).email("existing@example.com").build();
+        when(userRepository.findByEmail("existing@example.com")).thenReturn(Optional.of(existing));
+        when(passwordEncoder.encode(any())).thenReturn("encoded");
+        when(userRepository.save(any())).thenReturn(existing);
+
+        userService.createUserOrUpdate(actorId, req);
+
+        verify(auditService, never()).logAfterCommit(any(), any(), any(), any());
+    }
+
+    // ─── createUserForBootstrap ───────────────────────────────────────────────
+
+    @Test
+    void createUserForBootstrap_createsUserWithoutAuditEvent() {
+        CreateUserRequest req = new CreateUserRequest();
+        req.setEmail("bootstrap@example.com");
+        req.setInitialPassword("secret");
+        req.setGroupIds(List.of());
+
+        when(userRepository.findByEmail("bootstrap@example.com")).thenReturn(Optional.empty());
+        when(passwordEncoder.encode("secret")).thenReturn("encoded");
+        AppUser saved = AppUser.builder().id(UUID.randomUUID()).email("bootstrap@example.com").build();
+        when(userRepository.save(any())).thenReturn(saved);
+
+        AppUser result = userService.createUserForBootstrap(req);
+
+        assertThat(result).isEqualTo(saved);
+        verify(auditService, never()).logAfterCommit(any(), any(), any(), any());
+    }
+
     // ─── createGroup ──────────────────────────────────────────────────────────
 
     @Test