cicd

issue observers

Наблюдатели задачи видят её и комментируют, но не редактируют.

- таблица issue_observer, наблюдатели — часть сущности Issue
- видимость: reporter, assignee или наблюдатель (задачи, история, SSE)
- правка/удаление задачи и вложений — только reporter/assignee (403 наблюдателю)
- observers в create/update, DELETE /issues/:id/observers/me, фильтр role
- история изменений и уведомления новым наблюдателям

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

.dockerignore

@@ -11,3 +11,5 @@ coverage
 tsconfig.build.tsbuildinfo
 src/generated
 storage
+configs
+service-account.json

.gitea/workflows/deploy.yaml

@@ -1,4 +1,4 @@
-name: Gitea Actions Demo
+name: Gitea Actions
 run-name: Deploy 🚀
 on:
   push:
@@ -15,7 +15,7 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - name: Checkout repository
-        uses: actions/checkout@v6
+        uses: actions/checkout@v7
       - name: Docker build
         run: docker build --tag ${{ env.IMAGE_NAME }} .
       - name: Login to gitea

.gitignore

@@ -61,3 +61,5 @@ report.[0-9]*.[0-9]*.[0-9]*.[0-9]*.json
 
 # Local file storage (FILE_STORAGE=local)
 /storage
+/configs
+configs/service-account.json

README_PRISMA.md

@@ -1,3 +1,4 @@
+# Prisma
 
 npm install prisma@7 --save-dev
 

package.json

@@ -24,48 +24,47 @@
   "dependencies": {
     "@apollo/server": "^5.5.1",
     "@as-integrations/express5": "^1.1.2",
-    "@aws-sdk/client-s3": "^3.1145.0",
+    "@aws-sdk/client-s3": "^3.1152.0",
-    "@better-auth/prisma-adapter": "^1.7.2",
+    "@better-auth/prisma-adapter": "^1.7.11",
     "@nestjs/apollo": "^14.0.0",
-    "@nestjs/common": "^12.0.1",
+    "@nestjs/common": "^12.2.0",
-    "@nestjs/config": "^12.0.0",
+    "@nestjs/config": "^12.0.1",
-    "@nestjs/core": "^12.0.1",
+    "@nestjs/core": "^12.2.0",
     "@nestjs/event-emitter": "^12.0.1",
     "@nestjs/graphql": "^14.0.0",
-    "@nestjs/platform-express": "^12.0.1",
+    "@nestjs/platform-express": "^12.2.0",
     "@nestjs/schedule": "^12.0.2",
-    "@nestjs/typeorm": "^12.0.1",
     "@prisma/adapter-pg": "^7.10.0",
     "@prisma/client": "^7.10.0",
-    "@thallesp/nestjs-better-auth": "^2.7.0",
+    "@thallesp/nestjs-better-auth": "^2.8.0",
-    "better-auth": "^1.7.2",
+    "better-auth": "^1.7.11",
     "class-transformer": "^0.5.1",
     "class-validator": "^0.15.1",
-    "file-type": "^22.1.1",
+    "file-type": "^22.2.0",
+    "firebase-admin": "^14.5.0",
     "graphql": "^16.14.2",
-    "nodemailer": "^10.0.0",
+    "nodemailer": "^10.1.7",
     "pg": "^8.23.0",
     "reflect-metadata": "^0.2.2",
     "rxjs": "^7.8.1",
-    "typeorm": "^1.1.1",
+    "valibot": "^1.5.0"
-    "valibot": "^1.4.2"
   },
   "devDependencies": {
     "@nestjs/cli": "^12.0.0",
-    "@nestjs/mau": "^0.2.6",
+    "@nestjs/mau": "^0.2.8",
     "@nestjs/schematics": "^12.0.0",
-    "@nestjs/testing": "^12.0.1",
+    "@nestjs/testing": "^12.2.0",
     "@types/express": "^5.0.0",
     "@types/multer": "^2.3.0",
     "@types/node": "^24.0.0",
     "@types/pg": "^8.23.1",
-    "@types/supertest": "^7.0.0",
+    "@types/supertest": "^7.2.1",
     "@vitest/coverage-v8": "^4.1.2",
-    "oxlint": "^1.58.0",
+    "oxlint": "^1.88.0",
-    "prettier": "^3.4.2",
+    "prettier": "^3.9.10",
     "prisma": "^7.10.0",
     "source-map-support": "^0.5.21",
-    "supertest": "^7.0.0",
+    "supertest": "^7.3.1",
     "typescript": "^6.0.2",
     "vite-tsconfig-paths": "^5.1.4",
     "vitest": "^4.1.2"

prisma/migrations/20261007120000_issue_change/migration.sql

@@ -0,0 +1,28 @@
+-- CreateTable
+CREATE TABLE "issue_change" (
+    "id" SERIAL NOT NULL,
+    "issueId" INTEGER NOT NULL,
+    "changeId" TEXT NOT NULL,
+    "field" TEXT NOT NULL,
+    "oldValue" TEXT,
+    "newValue" TEXT,
+    "actorId" TEXT,
+    "changedAt" TIMESTAMPTZ(3) NOT NULL,
+
+    CONSTRAINT "issue_change_pkey" PRIMARY KEY ("id")
+);
+
+-- CreateIndex
+CREATE INDEX "issue_change_issueId_changedAt_idx" ON "issue_change"("issueId", "changedAt");
+
+-- CreateIndex
+CREATE INDEX "issue_change_field_changedAt_idx" ON "issue_change"("field", "changedAt");
+
+-- CreateIndex
+CREATE INDEX "issue_change_actorId_idx" ON "issue_change"("actorId");
+
+-- AddForeignKey
+ALTER TABLE "issue_change" ADD CONSTRAINT "issue_change_issueId_fkey" FOREIGN KEY ("issueId") REFERENCES "issue"("id") ON DELETE CASCADE ON UPDATE CASCADE;
+
+-- AddForeignKey
+ALTER TABLE "issue_change" ADD CONSTRAINT "issue_change_actorId_fkey" FOREIGN KEY ("actorId") REFERENCES "user"("id") ON DELETE SET NULL ON UPDATE CASCADE;

prisma/migrations/20261012120000_issue_project_due_date_index/migration.sql

@@ -0,0 +1,2 @@
+-- CreateIndex
+CREATE INDEX "issue_projectId_dueDate_idx" ON "issue"("projectId", "dueDate");

prisma/migrations/20261018173111_issue_type/migration.sql

@@ -0,0 +1,5 @@
+-- AlterTable
+ALTER TABLE "issue" ADD COLUMN     "type" TEXT NOT NULL DEFAULT 'TASK';
+
+-- CreateIndex
+CREATE INDEX "issue_projectId_type_idx" ON "issue"("projectId", "type");

prisma/migrations/20261023120000_user_avatar/migration.sql

@@ -0,0 +1,9 @@
+-- AlterTable
+ALTER TABLE "user" ADD COLUMN     "avatarFileId" TEXT;
+
+-- CreateIndex
+CREATE UNIQUE INDEX "user_avatarFileId_key" ON "user"("avatarFileId");
+
+-- AddForeignKey
+ALTER TABLE "user" ADD CONSTRAINT "user_avatarFileId_fkey" FOREIGN KEY ("avatarFileId") REFERENCES "file"("id") ON DELETE SET NULL ON UPDATE CASCADE;
+

prisma/migrations/20261025190802_issue_observer/migration.sql

@@ -0,0 +1,17 @@
+-- CreateTable
+CREATE TABLE "issue_observer" (
+    "issueId" INTEGER NOT NULL,
+    "userId" TEXT NOT NULL,
+    "createdAt" TIMESTAMPTZ(3) NOT NULL DEFAULT CURRENT_TIMESTAMP,
+
+    CONSTRAINT "issue_observer_pkey" PRIMARY KEY ("issueId","userId")
+);
+
+-- CreateIndex
+CREATE INDEX "issue_observer_userId_idx" ON "issue_observer"("userId");
+
+-- AddForeignKey
+ALTER TABLE "issue_observer" ADD CONSTRAINT "issue_observer_issueId_fkey" FOREIGN KEY ("issueId") REFERENCES "issue"("id") ON DELETE CASCADE ON UPDATE CASCADE;
+
+-- AddForeignKey
+ALTER TABLE "issue_observer" ADD CONSTRAINT "issue_observer_userId_fkey" FOREIGN KEY ("userId") REFERENCES "user"("id") ON DELETE CASCADE ON UPDATE CASCADE;

prisma/migrations/20261025192028_project_member_role/migration.sql

@@ -0,0 +1,5 @@
+-- CreateEnum
+CREATE TYPE "ProjectRole" AS ENUM ('MEMBER', 'OBSERVER');
+
+-- AlterTable
+ALTER TABLE "project_member" ADD COLUMN     "role" "ProjectRole" NOT NULL DEFAULT 'MEMBER';

prisma/migrations/20261028120000_tag/migration.sql

@@ -0,0 +1,37 @@
+-- CreateTable
+CREATE TABLE "tag" (
+    "id" TEXT NOT NULL,
+    "projectId" TEXT NOT NULL,
+    "name" TEXT NOT NULL,
+    "normalizedName" TEXT NOT NULL,
+    "color" TEXT NOT NULL DEFAULT 'default',
+    "createdAt" TIMESTAMPTZ(3) NOT NULL DEFAULT CURRENT_TIMESTAMP,
+    "updatedAt" TIMESTAMPTZ(3) NOT NULL,
+
+    CONSTRAINT "tag_pkey" PRIMARY KEY ("id")
+);
+
+-- CreateTable
+CREATE TABLE "issue_tag" (
+    "issueId" INTEGER NOT NULL,
+    "tagId" TEXT NOT NULL,
+    "createdAt" TIMESTAMPTZ(3) NOT NULL DEFAULT CURRENT_TIMESTAMP,
+
+    CONSTRAINT "issue_tag_pkey" PRIMARY KEY ("issueId","tagId")
+);
+
+-- CreateIndex
+CREATE UNIQUE INDEX "tag_projectId_normalizedName_key" ON "tag"("projectId", "normalizedName");
+
+-- CreateIndex
+CREATE INDEX "issue_tag_tagId_idx" ON "issue_tag"("tagId");
+
+-- AddForeignKey
+ALTER TABLE "tag" ADD CONSTRAINT "tag_projectId_fkey" FOREIGN KEY ("projectId") REFERENCES "project"("id") ON DELETE CASCADE ON UPDATE CASCADE;
+
+-- AddForeignKey
+ALTER TABLE "issue_tag" ADD CONSTRAINT "issue_tag_issueId_fkey" FOREIGN KEY ("issueId") REFERENCES "issue"("id") ON DELETE CASCADE ON UPDATE CASCADE;
+
+-- AddForeignKey
+ALTER TABLE "issue_tag" ADD CONSTRAINT "issue_tag_tagId_fkey" FOREIGN KEY ("tagId") REFERENCES "tag"("id") ON DELETE CASCADE ON UPDATE CASCADE;
+

prisma/schema.prisma

@@ -13,6 +13,10 @@ model User {
   email                    String
   emailVerified            Boolean                   @default(false)
   image                    String?
+  /// Файл аватара; image хранит его URL для better-auth и клиента.
+  /// Меняется только через PUT /users/me/avatar — там проверяется, что файл свой.
+  avatarFileId             String?                   @unique
+  avatarFile               File?                     @relation(name: "userAvatar", fields: [avatarFileId], references: [id], onDelete: SetNull)
   createdAt                DateTime                  @default(now())
   updatedAt                DateTime                  @updatedAt
   sessions                 Session[]
@@ -25,7 +29,9 @@ model User {
   notificationPreferences  NotificationPreference[]
   notificationMessages     NotificationMessage[]
   comments                 Comment[]
-  uploadedFiles            File[]
+  uploadedFiles            File[]                    @relation(name: "fileUploader")
+  issueChanges             IssueChange[]
+  observedIssues           IssueObserver[]
 
   @@unique([email])
   @@map("user")
@@ -87,6 +93,7 @@ model Issue {
   content     String?
   status      String
   priority    Int               @default(0)
+  type        String            @default("TASK")
   assigneeId  String?
   assignee    User?             @relation(name: "assigneeIssues", fields: [assigneeId], references: [id], onDelete: SetNull)
   reporterId  String?
@@ -96,6 +103,9 @@ model Issue {
   dueDate     DateTime?         @db.Timestamptz(3)
   comments    Comment[]
   attachments IssueAttachment[]
+  changes     IssueChange[]
+  observers   IssueObserver[]
+  tags        IssueTag[]
   createdAt   DateTime          @default(now()) @db.Timestamptz(3)
   updatedAt   DateTime          @updatedAt @db.Timestamptz(3)
 
@@ -106,9 +116,26 @@ model Issue {
   @@index([createdAt])
   @@index([projectId, createdAt])
   @@index([dueDate])
+  @@index([projectId, dueDate])
+  @@index([projectId, type])
   @@map("issue")
 }
 
+/// Наблюдатель задачи: видит её и может комментировать, но не редактировать.
+/// Редактируют задачу только reporter и assignee.
+model IssueObserver {
+  issueId   Int
+  userId    String
+  createdAt DateTime @default(now()) @db.Timestamptz(3)
+
+  issue Issue @relation(fields: [issueId], references: [id], onDelete: Cascade)
+  user  User  @relation(fields: [userId], references: [id], onDelete: Cascade)
+
+  @@id([issueId, userId])
+  @@index([userId])
+  @@map("issue_observer")
+}
+
 model Project {
   id        String          @id @default(uuid(7))
   name      String
@@ -119,6 +146,7 @@ model Project {
   ownerId   String
   owner     User            @relation(fields: [ownerId], references: [id], onDelete: Restrict)
   members   ProjectMember[]
+  tags      Tag[]
 
   @@unique([key])
   @@index([createdAt])
@@ -126,10 +154,50 @@ model Project {
   @@map("project")
 }
 
+/// Тег — элемент справочника проекта. Уникален в проекте без учёта регистра:
+/// normalizedName — name в нижнем регистре. color — из палитры (TAG_COLORS),
+/// валидируется в коде. Задаче тег назначают по имени — отсутствующий создаётся.
+model Tag {
+  id             String     @id @default(uuid(7))
+  projectId      String
+  project        Project    @relation(fields: [projectId], references: [id], onDelete: Cascade)
+  name           String
+  normalizedName String
+  color          String     @default("default")
+  issues         IssueTag[]
+  createdAt      DateTime   @default(now()) @db.Timestamptz(3)
+  updatedAt      DateTime   @updatedAt @db.Timestamptz(3)
+
+  @@unique([projectId, normalizedName])
+  @@map("tag")
+}
+
+/// Тег задачи. Удаление тега из справочника снимает его со всех задач (без записи в историю).
+model IssueTag {
+  issueId   Int
+  tagId     String
+  createdAt DateTime @default(now()) @db.Timestamptz(3)
+
+  issue Issue @relation(fields: [issueId], references: [id], onDelete: Cascade)
+  tag   Tag   @relation(fields: [tagId], references: [id], onDelete: Cascade)
+
+  @@id([issueId, tagId])
+  @@index([tagId])
+  @@map("issue_tag")
+}
+
+/// MEMBER создаёт задачи в проекте; OBSERVER только видит проект —
+/// он наблюдает за отдельными задачами (IssueObserver).
+enum ProjectRole {
+  MEMBER
+  OBSERVER
+}
+
 model ProjectMember {
   id        String      @id @default(uuid(7))
   projectId String
   userId    String
+  role      ProjectRole @default(MEMBER)
   createdAt DateTime    @default(now()) @db.Timestamptz(3)
 
   project Project @relation(fields: [projectId], references: [id], onDelete: Cascade)
@@ -224,11 +292,12 @@ model File {
   mimeType   String
   size       Int
   uploaderId String?
-  uploader   User?    @relation(fields: [uploaderId], references: [id], onDelete: SetNull)
+  uploader   User?    @relation(name: "fileUploader", fields: [uploaderId], references: [id], onDelete: SetNull)
   createdAt  DateTime @default(now()) @db.Timestamptz(3)
 
   issueAttachments   IssueAttachment[]
   commentAttachments CommentAttachment[]
+  avatarOf           User?             @relation(name: "userAvatar")
 
   @@unique([storageKey])
   @@index([uploaderId])
@@ -264,3 +333,31 @@ model CommentAttachment {
   @@index([fileId])
   @@map("comment_attachment")
 }
+
+/// История изменений задачи — одна строка на изменённое поле.
+/// Строки одного сохранения задачи объединены общим changeId.
+/// field: created | title | content | status | priority | type | assignee | dueDate | observer | tag
+/// (валидируется в коде, см. ISSUE_CHANGE_FIELDS). Значения — строки:
+/// priority — число, dueDate — ISO-дата, assignee — id пользователя.
+/// observer и tag — по строке на добавленный (oldValue = null) или снятый (newValue = null) элемент;
+/// observer — id пользователя, tag — имя тега на момент изменения.
+/// При создании задачи пишутся две строки: created и status null -> OPEN,
+/// поэтому статус задачи на любой момент восстанавливается по строкам status.
+/// У задач, созданных до появления истории, строк нет — в статистику они не попадают.
+model IssueChange {
+  id        Int      @id @default(autoincrement())
+  issueId   Int
+  issue     Issue    @relation(fields: [issueId], references: [id], onDelete: Cascade)
+  changeId  String
+  field     String
+  oldValue  String?
+  newValue  String?
+  actorId   String?
+  actor     User?    @relation(fields: [actorId], references: [id], onDelete: SetNull)
+  changedAt DateTime @db.Timestamptz(3)
+
+  @@index([issueId, changedAt])
+  @@index([field, changedAt])
+  @@index([actorId])
+  @@map("issue_change")
+}

src/app.module.ts

@@ -5,10 +5,13 @@ import { IssueModule } from './modules/issue/issue.module.js';
 import { ProjectModule } from './modules/project/project.module.js';
 import { UserModule } from './modules/user/user.module.js';
 import { StatusModule } from './modules/status/status.module.js';
+import { IssueTypeModule } from './modules/issue-type/issue-type.module.js';
 import { NotificationModule } from './modules/notification/notification.module.js';
 import { CommentModule } from './modules/comment/comment.module.js';
 import { FileModule } from './modules/file/file.module.js';
 import { IssueAttachmentModule } from './modules/issue-attachment/issue-attachment.module.js';
+import { HistoryModule } from './modules/history/history.module.js';
+import { TagModule } from './modules/tag/tag.module.js';
 import { AuthModule } from '@thallesp/nestjs-better-auth';
 import { auth } from './lib/auth.js';
 import { ConfigModule } from '@nestjs/config';
@@ -24,21 +27,13 @@ import { join } from 'node:path';
       isGlobal: true,
       cache: true,
     }),
-    // Внутрипроцессная шина доменных событий. Notification-модуль слушает
-    // события через неё, не завязываясь на модули, которые их порождают.
     EventEmitterModule.forRoot(),
-    // Периодические задачи (@Cron), например сборка файлов-сирот в FileModule
     ScheduleModule.forRoot(),
     GraphQLModule.forRoot<ApolloDriverConfig>({
       driver: ApolloDriver,
       autoSchemaFile: join(process.cwd(), 'src/schema.gql'),
       sortSchema: true,
     }),
-    // TypeOrmModule.forRootAsync({
-    //   imports: [ConfigModule],
-    //   inject: [ConfigService],
-    //   useFactory: pgConfig,
-    // }),
     AuthModule.forRoot({
       auth: auth,
       bodyParser: {
@@ -51,10 +46,13 @@ import { join } from 'node:path';
     ProjectModule,
     UserModule,
     StatusModule,
+    IssueTypeModule,
     NotificationModule,
     CommentModule,
     FileModule,
     IssueAttachmentModule,
+    HistoryModule,
+    TagModule,
   ],
   controllers: [AppController],
   providers: [AppService],

src/common/decorators/validators.ts

@@ -1,5 +1,5 @@
 import { Transform, TransformFnParams } from 'class-transformer';
-import { IsInt, IsNotEmpty, IsOptional, IsString, Max, MaxLength, Min } from 'class-validator';
+import { IsBoolean, IsInt, IsNotEmpty, IsOptional, IsString, Max, Min } from 'class-validator';
 import { applyDecorators } from '@nestjs/common';
 
 interface ToStringOptions {
@@ -11,6 +11,7 @@ interface BaseDecoratorParams {
 }
 
 export interface StringDecoratorParams extends BaseDecoratorParams {}
+export interface BooleanDecoratorParams extends BaseDecoratorParams {}
 export interface IntDecoratorParams extends BaseDecoratorParams {
   min?: number;
   max?: number;
@@ -24,6 +25,15 @@ const ToNumber = () =>
     return Number.isNaN(parsed) ? undefined : parsed;
   });
 
+/** Query-параметры приходят строками: 'true'/'false' → boolean, остальное оставляем как есть для IsBoolean */
+const ToBoolean = () =>
+  Transform(({ value }) => {
+    if (value === undefined || value === null || value === '') return undefined;
+    if (value === 'true') return true;
+    if (value === 'false') return false;
+    return value;
+  });
+
 const ToString = (options?: ToStringOptions) =>
   Transform(({ value }: TransformFnParams) => {
     if (value === undefined || value === null) return undefined;
@@ -52,3 +62,11 @@ export function IntDecorator(params?: IntDecoratorParams) {
 
   return applyDecorators(...args);
 }
+
+export function BooleanDecorator(params?: BooleanDecoratorParams) {
+  const args = [IsBoolean(), ToBoolean()];
+
+  if (params?.isOptional) args.push(IsOptional());
+
+  return applyDecorators(...args);
+}

src/configs/db.config.ts

@@ -1,7 +1,6 @@
 import { ConfigService } from '@nestjs/config';
-import { TypeOrmModuleOptions } from '@nestjs/typeorm';
 
-export function pgConfig(config: ConfigService): TypeOrmModuleOptions {
+export function pgConfig(config: ConfigService): unknown {
   return {
     type: 'postgres',
     url: config.getOrThrow<string>('DATABASE_URL'),

src/lib/auth.ts

@@ -2,12 +2,35 @@ import { betterAuth } from 'better-auth';
 import { prismaAdapter } from '@better-auth/prisma-adapter';
 import prisma from './prisma.js';
 import EmailSender from './email-sender.js';
+import { emailOTP } from 'better-auth/plugins';
 
 export const auth = betterAuth({
   appName: process.env.APP_NAME ?? 'app',
   basePath: '/api/auth',
   plugins: [
     // authTransformResponse()
+    emailOTP({
+      async sendVerificationOTP({ email, otp, type }) {
+        if (type === 'sign-in') {
+          EmailSender.sendInBackground({
+            to: email,
+            subject: `Your OTP code is: ${otp}`,
+            text: `Your OTP code is: ${otp}`,
+          });
+        } else if (type === 'email-verification') {
+          // Send the OTP for email verification
+          console.log({ email, otp, type });
+        } else if (type === 'forget-password') {
+          EmailSender.sendInBackground({
+            to: email,
+            subject: `Your password reset code is: ${otp}`,
+            text: `Your password reset code is: ${otp}`,
+          });
+        } else {
+          console.log({ email, otp, type });
+        }
+      },
+    }),
   ],
   database: prismaAdapter(prisma, {
     provider: 'postgresql',
@@ -24,28 +47,23 @@ export const auth = betterAuth({
   emailAndPassword: {
     enabled: true,
     autoSignIn: false,
-    requireEmailVerification: false,
+    requireEmailVerification: true,
     onExistingUserSignUp: async ({ user }, request) => {
-      console.log('onExistingUserSignUp', { user });
+      EmailSender.sendInBackground({
-
-      void EmailSender.getTransporter().sendMail({
         to: user.email,
         subject: 'Sign-up attempt with your email',
         text: 'Someone tried to create an account using your email address. If this was you, try signing in instead. If not, you can safely ignore this email.',
       });
     },
     sendResetPassword: async ({ user, url, token }, request) => {
-      console.log('sendResetPassword', { user, url, token });
+      EmailSender.sendInBackground({
-      void EmailSender.getTransporter().sendMail({
         to: user.email,
         subject: 'Reset your password',
         text: `Click the link to reset your password: ${url}`,
       });
     },
     onPasswordReset: async ({ user }, request) => {
-      // your logic here
+      EmailSender.sendInBackground({
-      console.log('onPasswordReset', { user });
-      void EmailSender.getTransporter().sendMail({
         to: user.email,
         subject: 'Reset your password result',
         text: `Password for user ${user.email} has been reset.`,
@@ -56,8 +74,7 @@ export const auth = betterAuth({
     sendOnSignIn: true,
     autoSignInAfterVerification: true,
     sendVerificationEmail: async ({ user, url }) => {
-      console.log('emailVerification', { user, url });
+      EmailSender.sendInBackground({
-      void EmailSender.getTransporter().sendMail({
         to: user.email,
         subject: 'Verify your email address',
         text: `Click the link to verify your email: ${url}`,

src/lib/email-sender.ts

@@ -1,13 +1,44 @@
+import { Logger } from '@nestjs/common';
 import nodemailer, { SendMailOptions, Transporter } from 'nodemailer';
 
 export default class EmailSender {
-  static getTransporter() {
+  private static readonly logger = new Logger(EmailSender.name);
-    return nodemailer.createTransport({
+  private static transporter?: Transporter;
+
+  private static isLocal() {
+    return process.env.NODE_ENV === 'local';
+  }
+
+  private static getTransporter() {
+    this.transporter ??= nodemailer.createTransport({
       service: 'gmail',
       auth: {
         user: process.env.GOOGLE_APP_USER,
         pass: process.env.GOOGLE_APP_PASSWORD,
       },
     });
+    return this.transporter;
+  }
+
+  /** Sends an email; throws on failure. In local env only logs the message. */
+  static async send(options: SendMailOptions): Promise<void> {
+    if (this.isLocal()) {
+      this.logger.log(
+        `[local] email not sent\n  to: ${String(options.to)}\n  subject: ${options.subject}\n  text: ${String(options.text)}`,
+      );
+      return;
+    }
+
+    await this.getTransporter().sendMail(options);
+  }
+
+  /** Fire-and-forget variant: never throws, errors are logged. */
+  static sendInBackground(options: SendMailOptions): void {
+    this.send(options).catch((error: unknown) => {
+      this.logger.error(
+        `Failed to send email "${options.subject}" to ${String(options.to)}`,
+        error instanceof Error ? error.stack : String(error),
+      );
+    });
   }
 }

src/main.ts

@@ -16,12 +16,7 @@ async function bootstrap() {
     logger: new CustomLogger(),
   });
 
-  // app.useGlobalPipes(new StandardSchemaValidationPipe());
-
   app.setGlobalPrefix('api');
-
-  // Глобальный body-parser отключён (better-auth сам парсит своё тело),
-  // поэтому для GraphQL включаем JSON-парсинг точечно на его пути.
   app.use('/graphql', json());
   app.useGlobalPipes(new ValidationPipe({ whitelist: true, transform: true }));
   app.useGlobalInterceptors(new TransformResponseInterceptor());

src/modules/comment/application/use-cases/test-helpers.ts

@@ -29,6 +29,7 @@ export const buildIssue = () =>
     content: null,
     status: 'OPEN',
     priority: 0,
+    type: 'TASK',
     assignee: null,
     reporter: 'user-1',
     projectId: 'project-1',
@@ -50,6 +51,7 @@ export const mockIssueRepository = (): IIssueRepository => ({
   findById: vi.fn(),
   findByCKey: vi.fn(),
   findAll: vi.fn(),
+  findByDueDateRange: vi.fn(),
   countByStatus: vi.fn(),
   create: vi.fn(),
   update: vi.fn(),

src/modules/history/application/dto/daily-issue-stats.dto.ts

@@ -0,0 +1,22 @@
+import type { IssueStatusValue } from '../../../issue/domain/value-objects/issue-status.vo.js';
+
+/** Счётчик по каждому статусу; статусы без задач — 0 */
+export type IssueStatusCounts = Record<IssueStatusValue, number>;
+
+export class DailyIssueStatsDayDto {
+  /** YYYY-MM-DD в часовом поясе запроса */
+  date: string;
+  /** Создано задач за день */
+  created: number;
+  /** Переходов в статус за день (создание задачи в OPEN сюда не входит). transitions.DONE — выполнено за день */
+  transitions: IssueStatusCounts;
+  /** Задач в каждом статусе на конец дня */
+  byStatus: IssueStatusCounts;
+}
+
+export class DailyIssueStatsDto {
+  from: string;
+  to: string;
+  timeZone: string;
+  days: DailyIssueStatsDayDto[];
+}

src/modules/history/application/dto/issue-history.dto.ts

@@ -0,0 +1,21 @@
+import type { IssueChangeField } from '../../../issue/domain/entities/issue-change.js';
+import { UserDto } from '../../../user/application/dto/user.dto.js';
+
+export class IssueFieldChangeDto {
+  field: IssueChangeField;
+  oldValue: string | null;
+  newValue: string | null;
+  /** Только для field = assignee/observer: пользователи из oldValue/newValue (null — не назначен или удалён) */
+  oldUser?: UserDto | null;
+  newUser?: UserDto | null;
+}
+
+/** Одно сохранение задачи: кто, когда и какие поля изменил */
+export class IssueHistoryEntryDto {
+  /** changeId */
+  id: string;
+  changedAt: Date;
+  actorId: string | null;
+  actor: UserDto | null;
+  changes: IssueFieldChangeDto[];
+}

src/modules/history/application/use-cases/get-daily-issue-stats/get-daily-issue-stats.query.ts

@@ -0,0 +1,12 @@
+export class GetDailyIssueStatsQuery {
+  constructor(
+    public readonly userId: string,
+    public readonly projectId?: string,
+    /** YYYY-MM-DD */
+    public readonly from?: string,
+    /** YYYY-MM-DD */
+    public readonly to?: string,
+    /** IANA, например Europe/Moscow */
+    public readonly timeZone?: string,
+  ) {}
+}

src/modules/history/application/use-cases/get-daily-issue-stats/get-daily-issue-stats.use-case.spec.ts

@@ -0,0 +1,77 @@
+import { beforeEach, describe, expect, it, vi } from 'vitest';
+import type { IIssueHistoryRepository } from '../../../domain/repositories/issue-history.repository.interface.js';
+import { InvalidStatsPeriodException } from '../../../domain/exceptions/invalid-stats-period.exception.js';
+import { GetDailyIssueStatsUseCase } from './get-daily-issue-stats.use-case.js';
+import { GetDailyIssueStatsQuery } from './get-daily-issue-stats.query.js';
+
+const zero = { OPEN: 0, IN_PROGRESS: 0, DONE: 0, CANCELLED: 0 };
+
+describe('GetDailyIssueStatsUseCase', () => {
+  let repository: IIssueHistoryRepository;
+  let useCase: GetDailyIssueStatsUseCase;
+
+  beforeEach(() => {
+    repository = {
+      findByIssue: vi.fn(),
+      countDailyEvents: vi.fn().mockResolvedValue([]),
+      countDailyStatuses: vi.fn().mockResolvedValue([]),
+    };
+    useCase = new GetDailyIssueStatsUseCase(repository);
+  });
+
+  it('passes the validated period and visibility params to the repository', async () => {
+    await useCase.execute(
+      new GetDailyIssueStatsQuery('user-1', 'project-1', '2026-10-01', '2026-10-03', 'Europe/Moscow'),
+    );
+
+    const range = {
+      userId: 'user-1',
+      projectId: 'project-1',
+      from: '2026-10-01',
+      to: '2026-10-03',
+      timeZone: 'Europe/Moscow',
+    };
+    expect(repository.countDailyEvents).toHaveBeenCalledWith(range);
+    expect(repository.countDailyStatuses).toHaveBeenCalledWith(range);
+  });
+
+  it('fills every day and every status, including the empty ones', async () => {
+    vi.mocked(repository.countDailyEvents).mockResolvedValue([
+      { date: '2026-10-01', kind: 'created', count: 2 },
+      { date: '2026-10-03', kind: 'status', status: 'DONE', count: 1 },
+    ]);
+    vi.mocked(repository.countDailyStatuses).mockResolvedValue([
+      { date: '2026-10-01', status: 'OPEN', count: 2 },
+      { date: '2026-10-03', status: 'OPEN', count: 1 },
+      { date: '2026-10-03', status: 'DONE', count: 1 },
+    ]);
+
+    const result = await useCase.execute(new GetDailyIssueStatsQuery('user-1', undefined, '2026-10-01', '2026-10-03'));
+
+    expect(result).toEqual({
+      from: '2026-10-01',
+      to: '2026-10-03',
+      timeZone: 'UTC',
+      days: [
+        { date: '2026-10-01', created: 2, transitions: zero, byStatus: { ...zero, OPEN: 2 } },
+        { date: '2026-10-02', created: 0, transitions: zero, byStatus: zero },
+        { date: '2026-10-03', created: 0, transitions: { ...zero, DONE: 1 }, byStatus: { ...zero, OPEN: 1, DONE: 1 } },
+      ],
+    });
+  });
+
+  it('ignores statuses that are no longer known', async () => {
+    vi.mocked(repository.countDailyStatuses).mockResolvedValue([{ date: '2026-10-01', status: 'LEGACY', count: 5 }]);
+
+    const result = await useCase.execute(new GetDailyIssueStatsQuery('user-1', undefined, '2026-10-01', '2026-10-01'));
+
+    expect(result.days[0]!.byStatus).toEqual(zero);
+  });
+
+  it('rejects an invalid period without querying the database', async () => {
+    await expect(
+      useCase.execute(new GetDailyIssueStatsQuery('user-1', undefined, '2026-10-05', '2026-10-01')),
+    ).rejects.toThrow(InvalidStatsPeriodException);
+    expect(repository.countDailyEvents).not.toHaveBeenCalled();
+  });
+});

src/modules/history/application/use-cases/get-daily-issue-stats/get-daily-issue-stats.use-case.ts

@@ -0,0 +1,73 @@
+import { Inject, Injectable } from '@nestjs/common';
+import { ISSUE_STATUSES, type IssueStatusValue } from '../../../../issue/domain/value-objects/issue-status.vo.js';
+import {
+  ISSUE_HISTORY_REPOSITORY,
+  type IIssueHistoryRepository,
+} from '../../../domain/repositories/issue-history.repository.interface.js';
+import { StatsPeriod } from '../../../domain/value-objects/stats-period.vo.js';
+import { DailyIssueStatsDayDto, DailyIssueStatsDto, IssueStatusCounts } from '../../dto/daily-issue-stats.dto.js';
+import { GetDailyIssueStatsQuery } from './get-daily-issue-stats.query.js';
+
+/**
+ * Статистика задач по дням, считается по истории изменений (issue_change).
+ * Видимость — как у списка задач: только задачи, где пользователь reporter/assignee/наблюдатель.
+ */
+@Injectable()
+export class GetDailyIssueStatsUseCase {
+  constructor(
+    @Inject(ISSUE_HISTORY_REPOSITORY)
+    private readonly historyRepository: IIssueHistoryRepository,
+  ) {}
+
+  async execute(query: GetDailyIssueStatsQuery): Promise<DailyIssueStatsDto> {
+    const period = StatsPeriod.create({ from: query.from, to: query.to, timeZone: query.timeZone });
+    const range = {
+      userId: query.userId,
+      projectId: query.projectId,
+      from: period.from,
+      to: period.to,
+      timeZone: period.timeZone,
+    };
+
+    const [events, statuses] = await Promise.all([
+      this.historyRepository.countDailyEvents(range),
+      this.historyRepository.countDailyStatuses(range),
+    ]);
+
+    // Каждый день периода попадает в ответ, даже если в нём ничего не было
+    const days = new Map<string, DailyIssueStatsDayDto>(
+      period.days.map((date) => [
+        date,
+        { date, created: 0, transitions: emptyStatusCounts(), byStatus: emptyStatusCounts() },
+      ]),
+    );
+
+    for (const event of events) {
+      const day = days.get(event.date);
+      if (!day) continue;
+
+      if (event.kind === 'created') {
+        day.created += event.count;
+      } else if (isKnownStatus(event.status)) {
+        day.transitions[event.status] += event.count;
+      }
+    }
+
+    for (const entry of statuses) {
+      const day = days.get(entry.date);
+      if (day && isKnownStatus(entry.status)) {
+        day.byStatus[entry.status] += entry.count;
+      }
+    }
+
+    return { from: period.from, to: period.to, timeZone: period.timeZone, days: [...days.values()] };
+  }
+}
+
+function emptyStatusCounts(): IssueStatusCounts {
+  return Object.fromEntries(ISSUE_STATUSES.map((status) => [status.alias, 0])) as IssueStatusCounts;
+}
+
+function isKnownStatus(status: string): status is IssueStatusValue {
+  return ISSUE_STATUSES.some((known) => known.alias === status);
+}

src/modules/history/application/use-cases/get-issue-history/get-issue-history.query.ts

@@ -0,0 +1,6 @@
+export class GetIssueHistoryQuery {
+  constructor(
+    public readonly issueId: number,
+    public readonly userId: string,
+  ) {}
+}

src/modules/history/application/use-cases/get-issue-history/get-issue-history.use-case.spec.ts

@@ -0,0 +1,105 @@
+import { beforeEach, describe, expect, it, vi } from 'vitest';
+import type {
+  IIssueHistoryRepository,
+  IssueChangeRecord,
+} from '../../../domain/repositories/issue-history.repository.interface.js';
+import type { IIssueRepository } from '../../../../issue/domain/repositories/issue.repository.interface.js';
+import { Issue } from '../../../../issue/domain/entities/issue.entity.js';
+import { IssueNotFoundException } from '../../../../issue/domain/exceptions/issue-not-found.exception.js';
+import type { GetUsersUseCase } from '../../../../user/application/use-cases/get-users/get-users.use-case.js';
+import type { UserDto } from '../../../../user/application/dto/user.dto.js';
+import { GetIssueHistoryUseCase } from './get-issue-history.use-case.js';
+import { GetIssueHistoryQuery } from './get-issue-history.query.js';
+
+const buildIssue = () =>
+  Issue.reconstitute({
+    id: 1,
+    key: 'ISSUE-1',
+    title: 'Title',
+    content: null,
+    status: 'OPEN',
+    priority: 0,
+    type: 'TASK',
+    assignee: null,
+    reporter: 'user-1',
+    projectId: 'project-1',
+    dueDate: null,
+    createdAt: new Date('2026-10-01T00:00:00.000Z'),
+    updatedAt: new Date('2026-10-01T00:00:00.000Z'),
+  });
+
+const user = (id: string) => ({ id, name: id }) as UserDto;
+
+let nextId = 1;
+const record = (
+  props: Partial<IssueChangeRecord> & Pick<IssueChangeRecord, 'changeId' | 'field'>,
+): IssueChangeRecord => ({
+  id: nextId++,
+  issueId: 1,
+  oldValue: null,
+  newValue: null,
+  actorId: 'user-1',
+  changedAt: new Date('2026-10-01T00:00:00.000Z'),
+  ...props,
+});
+
+describe('GetIssueHistoryUseCase', () => {
+  let historyRepository: IIssueHistoryRepository;
+  let issueRepository: IIssueRepository;
+  let getUsersUseCase: GetUsersUseCase;
+  let useCase: GetIssueHistoryUseCase;
+
+  beforeEach(() => {
+    historyRepository = { findByIssue: vi.fn(), countDailyEvents: vi.fn(), countDailyStatuses: vi.fn() };
+    issueRepository = {
+      findById: vi.fn(),
+      findByCKey: vi.fn(),
+      findAll: vi.fn(),
+      findByDueDateRange: vi.fn(),
+      countByStatus: vi.fn(),
+      create: vi.fn(),
+      update: vi.fn(),
+      delete: vi.fn(),
+    };
+    getUsersUseCase = {
+      execute: vi.fn(async (query: { ids: string[] }) => query.ids.filter((id) => id !== 'deleted').map(user)),
+    } as unknown as GetUsersUseCase;
+    useCase = new GetIssueHistoryUseCase(historyRepository, issueRepository, getUsersUseCase);
+  });
+
+  it('throws IssueNotFoundException when the issue is not visible to the user', async () => {
+    vi.mocked(issueRepository.findById).mockResolvedValue(null);
+
+    await expect(useCase.execute(new GetIssueHistoryQuery(1, 'user-9'))).rejects.toThrow(IssueNotFoundException);
+    expect(issueRepository.findById).toHaveBeenCalledWith(1, 'user-9');
+    expect(historyRepository.findByIssue).not.toHaveBeenCalled();
+  });
+
+  it('groups rows of one save into an entry and expands actors and assignees', async () => {
+    vi.mocked(issueRepository.findById).mockResolvedValue(buildIssue());
+    vi.mocked(historyRepository.findByIssue).mockResolvedValue([
+      record({ changeId: 'c1', field: 'created' }),
+      record({ changeId: 'c1', field: 'status', newValue: 'OPEN' }),
+      record({ changeId: 'c2', field: 'status', oldValue: 'OPEN', newValue: 'DONE', actorId: 'user-2' }),
+      record({ changeId: 'c2', field: 'assignee', oldValue: 'deleted', newValue: 'user-3', actorId: 'user-2' }),
+    ]);
+
+    const entries = await useCase.execute(new GetIssueHistoryQuery(1, 'user-1'));
+
+    expect(entries.map((entry) => [entry.id, entry.actor?.id, entry.changes.map((change) => change.field)])).toEqual([
+      ['c1', 'user-1', ['created', 'status']],
+      ['c2', 'user-2', ['status', 'assignee']],
+    ]);
+    expect(entries[1]!.changes[0]).toEqual({ field: 'status', oldValue: 'OPEN', newValue: 'DONE' });
+    expect(entries[1]!.changes[1]).toMatchObject({ oldUser: null, newUser: { id: 'user-3' } });
+    expect(getUsersUseCase.execute).toHaveBeenCalledTimes(1);
+  });
+
+  it('does not query users for an empty history', async () => {
+    vi.mocked(issueRepository.findById).mockResolvedValue(buildIssue());
+    vi.mocked(historyRepository.findByIssue).mockResolvedValue([]);
+
+    expect(await useCase.execute(new GetIssueHistoryQuery(1, 'user-1'))).toEqual([]);
+    expect(getUsersUseCase.execute).not.toHaveBeenCalled();
+  });
+});

src/modules/history/application/use-cases/get-issue-history/get-issue-history.use-case.ts

@@ -0,0 +1,87 @@
+import { Inject, Injectable } from '@nestjs/common';
+import {
+  ISSUE_REPOSITORY,
+  type IIssueRepository,
+} from '../../../../issue/domain/repositories/issue.repository.interface.js';
+import { IssueNotFoundException } from '../../../../issue/domain/exceptions/issue-not-found.exception.js';
+import { GetUsersUseCase } from '../../../../user/application/use-cases/get-users/get-users.use-case.js';
+import { GetUsersQuery } from '../../../../user/application/use-cases/get-users/get-users.query.js';
+import type { UserDto } from '../../../../user/application/dto/user.dto.js';
+import {
+  ISSUE_HISTORY_REPOSITORY,
+  type IIssueHistoryRepository,
+  type IssueChangeRecord,
+} from '../../../domain/repositories/issue-history.repository.interface.js';
+import { IssueFieldChangeDto, IssueHistoryEntryDto } from '../../dto/issue-history.dto.js';
+import { GetIssueHistoryQuery } from './get-issue-history.query.js';
+import type { IssueChangeField } from '../../../../issue/domain/entities/issue-change.js';
+
+/** Поля, значения которых — id пользователей */
+const USER_FIELDS = new Set<IssueChangeField>(['assignee', 'observer']);
+
+@Injectable()
+export class GetIssueHistoryUseCase {
+  constructor(
+    @Inject(ISSUE_HISTORY_REPOSITORY)
+    private readonly historyRepository: IIssueHistoryRepository,
+    @Inject(ISSUE_REPOSITORY)
+    private readonly issueRepository: IIssueRepository,
+    private readonly getUsersUseCase: GetUsersUseCase,
+  ) {}
+
+  async execute(query: GetIssueHistoryQuery): Promise<IssueHistoryEntryDto[]> {
+    const issue = await this.issueRepository.findById(query.issueId, query.userId);
+    if (!issue) {
+      throw new IssueNotFoundException(query.issueId);
+    }
+
+    const records = await this.historyRepository.findByIssue(query.issueId);
+    const usersById = await this.loadUsers(records);
+    const userOf = (id: string | null) => (id ? (usersById.get(id) ?? null) : null);
+
+    // Строки одного сохранения объединяются по changeId, порядок — по первой строке
+    const entries = new Map<string, IssueHistoryEntryDto>();
+    for (const record of records) {
+      let entry = entries.get(record.changeId);
+      if (!entry) {
+        entry = {
+          id: record.changeId,
+          changedAt: record.changedAt,
+          actorId: record.actorId,
+          actor: userOf(record.actorId),
+          changes: [],
+        };
+        entries.set(record.changeId, entry);
+      }
+
+      const change: IssueFieldChangeDto = {
+        field: record.field,
+        oldValue: record.oldValue,
+        newValue: record.newValue,
+      };
+      if (USER_FIELDS.has(record.field)) {
+        change.oldUser = userOf(record.oldValue);
+        change.newUser = userOf(record.newValue);
+      }
+      entry.changes.push(change);
+    }
+
+    return [...entries.values()];
+  }
+
+  /** Авторы изменений, назначенные/снятые исполнители и наблюдатели */
+  private async loadUsers(records: IssueChangeRecord[]): Promise<Map<string, UserDto>> {
+    const ids = new Set<string>();
+    for (const record of records) {
+      if (record.actorId) ids.add(record.actorId);
+      if (USER_FIELDS.has(record.field)) {
+        if (record.oldValue) ids.add(record.oldValue);
+        if (record.newValue) ids.add(record.newValue);
+      }
+    }
+    if (ids.size === 0) return new Map();
+
+    const users = await this.getUsersUseCase.execute(new GetUsersQuery([...ids]));
+    return new Map(users.map((user) => [user.id, user]));
+  }
+}

src/modules/history/domain/exceptions/invalid-stats-period.exception.ts

@@ -0,0 +1,6 @@
+export class InvalidStatsPeriodException extends Error {
+  constructor(message: string) {
+    super(message);
+    this.name = 'InvalidStatsPeriodException';
+  }
+}

src/modules/history/domain/repositories/issue-history.repository.interface.ts

@@ -0,0 +1,46 @@
+import type { IssueChangeField } from '../../../issue/domain/entities/issue-change.js';
+
+/** DI-токен, т.к. интерфейсы стираются при компиляции TS */
+export const ISSUE_HISTORY_REPOSITORY = Symbol('ISSUE_HISTORY_REPOSITORY');
+
+/** Строка истории: изменение одного поля задачи (см. модель IssueChange) */
+export interface IssueChangeRecord {
+  id: number;
+  issueId: number;
+  /** Общий для всех полей, изменённых одним сохранением задачи */
+  changeId: string;
+  field: IssueChangeField;
+  oldValue: string | null;
+  newValue: string | null;
+  actorId: string | null;
+  changedAt: Date;
+}
+
+/** Период статистики: даты YYYY-MM-DD включительно, границы дней — в timeZone */
+export interface DailyStatsRange {
+  userId: string;
+  projectId?: string;
+  from: string;
+  to: string;
+  timeZone: string;
+}
+
+/** created — задачи, созданные за день; status — переходы в status за день (без начального OPEN) */
+export type DailyEventCount =
+  { date: string; kind: 'created'; count: number } | { date: string; kind: 'status'; status: string; count: number };
+
+/** Сколько задач было в статусе на конец дня */
+export interface DailyStatusCount {
+  date: string;
+  status: string;
+  count: number;
+}
+
+export interface IIssueHistoryRepository {
+  /** История задачи от старых изменений к новым */
+  findByIssue(issueId: number): Promise<IssueChangeRecord[]>;
+  /** Только задачи, видимые пользователю (reporter/assignee/наблюдатель) */
+  countDailyEvents(range: DailyStatsRange): Promise<DailyEventCount[]>;
+  /** Только задачи, видимые пользователю (reporter/assignee/наблюдатель) */
+  countDailyStatuses(range: DailyStatsRange): Promise<DailyStatusCount[]>;
+}

src/modules/history/domain/value-objects/stats-period.vo.spec.ts

@@ -0,0 +1,42 @@
+import { describe, expect, it } from 'vitest';
+import { StatsPeriod } from './stats-period.vo.js';
+import { InvalidStatsPeriodException } from '../exceptions/invalid-stats-period.exception.js';
+
+describe('StatsPeriod', () => {
+  const now = new Date('2026-10-07T22:30:00.000Z');
+
+  it('defaults to the last 30 days up to today in UTC', () => {
+    const period = StatsPeriod.create({}, now);
+
+    expect(period.from).toBe('2026-09-08');
+    expect(period.to).toBe('2026-10-07');
+    expect(period.timeZone).toBe('UTC');
+    expect(period.days).toHaveLength(30);
+  });
+
+  it('takes "today" in the requested time zone', () => {
+    // 22:30 UTC — в Москве уже 8 октября
+    expect(StatsPeriod.create({ timeZone: 'Europe/Moscow' }, now).to).toBe('2026-10-08');
+  });
+
+  it('lists every day of an explicit period inclusively', () => {
+    const period = StatsPeriod.create({ from: '2026-02-27', to: '2026-03-02' }, now);
+
+    expect(period.days).toEqual(['2026-02-27', '2026-02-28', '2026-03-01', '2026-03-02']);
+  });
+
+  it.each([
+    [{ from: '2026-10-05', to: '2026-10-01' }, 'from after to'],
+    [{ from: '2026-02-30' }, 'non-existent date'],
+    [{ to: '07.10.2026' }, 'wrong date format'],
+    [{ from: '2025-01-01', to: '2026-10-07' }, 'period too long'],
+    [{ timeZone: 'Mars/Olympus' }, 'unknown time zone'],
+    [{ timeZone: '+03:00' }, 'offset instead of IANA name'],
+  ] as const)('rejects %j (%s)', (params, _reason) => {
+    expect(() => StatsPeriod.create(params, now)).toThrow(InvalidStatsPeriodException);
+  });
+
+  it('accepts the maximum period length', () => {
+    expect(StatsPeriod.create({ from: '2025-10-07', to: '2026-10-07' }, now).days).toHaveLength(StatsPeriod.MAX_DAYS);
+  });
+});

src/modules/history/domain/value-objects/stats-period.vo.ts

@@ -0,0 +1,93 @@
+import { InvalidStatsPeriodException } from '../exceptions/invalid-stats-period.exception.js';
+
+const DATE_PATTERN = /^\d{4}-\d{2}-\d{2}$/;
+/**
+ * Только IANA-имена (Europe/Moscow, UTC). Смещения вида "+03:00" Intl понимает,
+ * а Postgres в AT TIME ZONE трактует по POSIX — с обратным знаком.
+ */
+const TIME_ZONE_PATTERN = /^[A-Za-z][A-Za-z0-9_+-]*(\/[A-Za-z0-9_+-]+)*$/;
+const DAY_MS = 24 * 60 * 60 * 1000;
+
+/**
+ * Период дневной статистики: from..to включительно (YYYY-MM-DD),
+ * границы дней считаются в часовом поясе timeZone.
+ */
+export class StatsPeriod {
+  static readonly MAX_DAYS = 366;
+  static readonly DEFAULT_DAYS = 30;
+
+  private constructor(
+    public readonly from: string,
+    public readonly to: string,
+    public readonly timeZone: string,
+  ) {}
+
+  /**
+   * Без to — сегодня в timeZone, без from — DEFAULT_DAYS дней до to.
+   * Без timeZone — UTC.
+   */
+  static create(params: { from?: string; to?: string; timeZone?: string }, now: Date = new Date()): StatsPeriod {
+    const timeZone = params.timeZone ?? 'UTC';
+    if (!isValidTimeZone(timeZone)) {
+      throw new InvalidStatsPeriodException(`Неизвестный часовой пояс: "${timeZone}"`);
+    }
+
+    const to = params.to !== undefined ? parseDate(params.to, 'to') : parseDate(todayIn(timeZone, now), 'to');
+    const from =
+      params.from !== undefined ? parseDate(params.from, 'from') : to - (StatsPeriod.DEFAULT_DAYS - 1) * DAY_MS;
+
+    if (from > to) {
+      throw new InvalidStatsPeriodException('Дата from позже даты to');
+    }
+
+    const days = (to - from) / DAY_MS + 1;
+    if (days > StatsPeriod.MAX_DAYS) {
+      throw new InvalidStatsPeriodException(`Период больше ${StatsPeriod.MAX_DAYS} дней`);
+    }
+
+    return new StatsPeriod(formatDate(from), formatDate(to), timeZone);
+  }
+
+  /** Все дни периода по порядку, YYYY-MM-DD */
+  get days(): string[] {
+    const days: string[] = [];
+    for (let day = Date.parse(this.from); day <= Date.parse(this.to); day += DAY_MS) {
+      days.push(formatDate(day));
+    }
+    return days;
+  }
+}
+
+function isValidTimeZone(timeZone: string): boolean {
+  if (!TIME_ZONE_PATTERN.test(timeZone)) return false;
+  try {
+    new Intl.DateTimeFormat('en-US', { timeZone });
+    return true;
+  } catch {
+    return false;
+  }
+}
+
+/** YYYY-MM-DD → полночь UTC в мс; несуществующие даты (02-30) отклоняются */
+function parseDate(value: string, name: string): number {
+  const time = DATE_PATTERN.test(value) ? Date.parse(value) : NaN;
+  if (Number.isNaN(time) || formatDate(time) !== value) {
+    throw new InvalidStatsPeriodException(`Некорректная дата ${name}: "${value}", ожидается YYYY-MM-DD`);
+  }
+  return time;
+}
+
+function formatDate(time: number): string {
+  return new Date(time).toISOString().slice(0, 10);
+}
+
+function todayIn(timeZone: string, now: Date): string {
+  const parts = new Intl.DateTimeFormat('en-US', {
+    timeZone,
+    year: 'numeric',
+    month: '2-digit',
+    day: '2-digit',
+  }).formatToParts(now);
+  const part = (type: Intl.DateTimeFormatPartTypes) => parts.find((p) => p.type === type)?.value;
+  return `${part('year')}-${part('month')}-${part('day')}`;
+}

src/modules/history/history.module.ts

@@ -0,0 +1,30 @@
+import { Module } from '@nestjs/common';
+import { PrismaModule } from '../../common/prisma-adapter/prisma.module.js';
+import { IssueModule } from '../issue/issue.module.js';
+import { UserModule } from '../user/user.module.js';
+import { ISSUE_HISTORY_REPOSITORY } from './domain/repositories/issue-history.repository.interface.js';
+import { IssueHistoryPrismaRepository } from './infrastructure/persistence/prisma/repositories/issue-history.prisma-repository.js';
+import { HistoryController } from './presentation/controllers/history.controller.js';
+import { GetIssueHistoryUseCase } from './application/use-cases/get-issue-history/get-issue-history.use-case.js';
+import { GetDailyIssueStatsUseCase } from './application/use-cases/get-daily-issue-stats/get-daily-issue-stats.use-case.js';
+
+/**
+ * Чтение истории изменений задач и статистика по ней. Пишет историю
+ * issue-модуль (IssuePrismaRepository) — в одной транзакции с задачей;
+ * этот модуль от issue зависит, issue о нём не знает.
+ */
+@Module({
+  imports: [PrismaModule, IssueModule, UserModule],
+  controllers: [HistoryController],
+  providers: [
+    GetIssueHistoryUseCase,
+    GetDailyIssueStatsUseCase,
+    {
+      // Domain видит только интерфейс IIssueHistoryRepository,
+      // конкретную реализацию (Prisma) подставляет DI-контейнер здесь
+      provide: ISSUE_HISTORY_REPOSITORY,
+      useClass: IssueHistoryPrismaRepository,
+    },
+  ],
+})
+export class HistoryModule {}

src/modules/history/infrastructure/persistence/prisma/repositories/issue-history.prisma-repository.ts

@@ -0,0 +1,90 @@
+import { Injectable } from '@nestjs/common';
+import { PrismaAdapter } from '../../../../../../common/prisma-adapter/prisma.adapter.js';
+import { Prisma } from '../../../../../../generated/prisma/client.js';
+import type { IssueChangeField } from '../../../../../issue/domain/entities/issue-change.js';
+import type {
+  DailyEventCount,
+  DailyStatsRange,
+  DailyStatusCount,
+  IIssueHistoryRepository,
+  IssueChangeRecord,
+} from '../../../../domain/repositories/issue-history.repository.interface.js';
+
+/**
+ * Задачи, видимые пользователю: reporter, assignee или наблюдатель — то же
+ * правило, что visibleTo в IssuePrismaRepository. Возвращает CTE "visible" (id задач).
+ */
+function visibleIssuesCte(range: DailyStatsRange): Prisma.Sql {
+  return Prisma.sql`"visible" AS (
+    SELECT "id" FROM "issue"
+    WHERE ("assigneeId" = ${range.userId} OR "reporterId" = ${range.userId}
+      OR EXISTS (SELECT 1 FROM "issue_observer" o WHERE o."issueId" = "issue"."id" AND o."userId" = ${range.userId}))
+    ${range.projectId ? Prisma.sql`AND "projectId" = ${range.projectId}` : Prisma.empty}
+  )`;
+}
+
+@Injectable()
+export class IssueHistoryPrismaRepository implements IIssueHistoryRepository {
+  constructor(private readonly prisma: PrismaAdapter) {}
+
+  async findByIssue(issueId: number): Promise<IssueChangeRecord[]> {
+    const records = await this.prisma.issueChange.findMany({
+      where: { issueId },
+      orderBy: [{ changedAt: 'asc' }, { id: 'asc' }],
+    });
+
+    return records.map((record) => ({ ...record, field: record.field as IssueChangeField }));
+  }
+
+  async countDailyEvents(range: DailyStatsRange): Promise<DailyEventCount[]> {
+    const rows = await this.prisma.$queryRaw<
+      Array<{ date: string; field: string; status: string | null; count: number }>
+    >`
+      WITH ${visibleIssuesCte(range)}
+      SELECT to_char((c."changedAt" AT TIME ZONE ${range.timeZone})::date, 'YYYY-MM-DD') AS "date",
+             c."field",
+             c."newValue" AS "status",
+             count(*)::int AS "count"
+      FROM "issue_change" c
+      JOIN "visible" v ON v."id" = c."issueId"
+      WHERE (c."field" = 'created' OR (c."field" = 'status' AND c."oldValue" IS NOT NULL))
+        AND c."changedAt" >= (${range.from}::date)::timestamp AT TIME ZONE ${range.timeZone}
+        AND c."changedAt" < (${range.to}::date + 1)::timestamp AT TIME ZONE ${range.timeZone}
+      GROUP BY 1, 2, 3
+    `;
+
+    return rows.map((row) =>
+      row.field === 'created'
+        ? { date: row.date, kind: 'created', count: row.count }
+        : { date: row.date, kind: 'status', status: row.status as string, count: row.count },
+    );
+  }
+
+  /**
+   * Статус задачи на конец дня — последний переход строго до полуночи
+   * следующего дня. Переходы превращаются в интервалы [validFrom, validTo),
+   * день засчитывается интервалу, который покрывает его конец.
+   */
+  async countDailyStatuses(range: DailyStatsRange): Promise<DailyStatusCount[]> {
+    return this.prisma.$queryRaw<DailyStatusCount[]>`
+      WITH ${visibleIssuesCte(range)},
+      "days" AS (
+        SELECT d::date AS "day",
+               (d::date + 1)::timestamp AT TIME ZONE ${range.timeZone} AS "dayEnd"
+        FROM generate_series(${range.from}::date, ${range.to}::date, interval '1 day') AS d
+      ),
+      "intervals" AS (
+        SELECT c."newValue" AS "status",
+               c."changedAt" AS "validFrom",
+               lead(c."changedAt") OVER (PARTITION BY c."issueId" ORDER BY c."changedAt", c."id") AS "validTo"
+        FROM "issue_change" c
+        JOIN "visible" v ON v."id" = c."issueId"
+        WHERE c."field" = 'status'
+      )
+      SELECT to_char(d."day", 'YYYY-MM-DD') AS "date", i."status", count(*)::int AS "count"
+      FROM "days" d
+      JOIN "intervals" i ON i."validFrom" < d."dayEnd" AND (i."validTo" IS NULL OR i."validTo" >= d."dayEnd")
+      GROUP BY d."day", i."status"
+    `;
+  }
+}

src/modules/history/presentation/controllers/history.controller.ts

@@ -0,0 +1,50 @@
+import { BadRequestException, Controller, Get, NotFoundException, Param, ParseIntPipe, Query } from '@nestjs/common';
+import { Session, type UserSession } from '@thallesp/nestjs-better-auth';
+import { GetIssueHistoryUseCase } from '../../application/use-cases/get-issue-history/get-issue-history.use-case.js';
+import { GetIssueHistoryQuery } from '../../application/use-cases/get-issue-history/get-issue-history.query.js';
+import { GetDailyIssueStatsUseCase } from '../../application/use-cases/get-daily-issue-stats/get-daily-issue-stats.use-case.js';
+import { GetDailyIssueStatsQuery } from '../../application/use-cases/get-daily-issue-stats/get-daily-issue-stats.query.js';
+import { DailyIssueStatsQueryDto } from '../dto/daily-issue-stats-query.dto.js';
+import { IssueNotFoundException } from '../../../issue/domain/exceptions/issue-not-found.exception.js';
+import { InvalidStatsPeriodException } from '../../domain/exceptions/invalid-stats-period.exception.js';
+
+@Controller('issues')
+export class HistoryController {
+  constructor(
+    private readonly getIssueHistoryUseCase: GetIssueHistoryUseCase,
+    private readonly getDailyIssueStatsUseCase: GetDailyIssueStatsUseCase,
+  ) {}
+
+  /** Статистика по дням: создано, переходы между статусами и срез статусов на конец дня */
+  @Get('stats/daily')
+  dailyStats(@Query() query: DailyIssueStatsQueryDto, @Session() session: UserSession) {
+    return this.handleErrors(() =>
+      this.getDailyIssueStatsUseCase.execute(
+        new GetDailyIssueStatsQuery(session.user.id, query.projectId, query.from, query.to, query.timeZone),
+      ),
+    );
+  }
+
+  /** История изменений задачи от старых к новым, одна запись на сохранение */
+  @Get(':issueId/history')
+  history(@Param('issueId', ParseIntPipe) issueId: number, @Session() session: UserSession) {
+    return this.handleErrors(() =>
+      this.getIssueHistoryUseCase.execute(new GetIssueHistoryQuery(issueId, session.user.id)),
+    );
+  }
+
+  /** Транслирует доменные исключения в HTTP-ответ — это забота presentation-слоя */
+  private async handleErrors<T>(fn: () => Promise<T>): Promise<T> {
+    try {
+      return await fn();
+    } catch (error) {
+      if (error instanceof IssueNotFoundException) {
+        throw new NotFoundException(error.message);
+      }
+      if (error instanceof InvalidStatsPeriodException) {
+        throw new BadRequestException(error.message);
+      }
+      throw error;
+    }
+  }
+}

src/modules/history/presentation/dto/daily-issue-stats-query.dto.ts

@@ -0,0 +1,18 @@
+import { StringDecorator } from '../../../../common/decorators/validators.js';
+
+export class DailyIssueStatsQueryDto {
+  @StringDecorator({ isOptional: true })
+  projectId?: string;
+
+  /** YYYY-MM-DD, по умолчанию — 30 дней до to */
+  @StringDecorator({ isOptional: true })
+  from?: string;
+
+  /** YYYY-MM-DD включительно, по умолчанию — сегодня в timeZone */
+  @StringDecorator({ isOptional: true })
+  to?: string;
+
+  /** IANA-имя, например Europe/Moscow; по умолчанию UTC */
+  @StringDecorator({ isOptional: true })
+  timeZone?: string;
+}

src/modules/issue-attachment/application/services/issue-attachment-file-owner.service.ts

@@ -36,7 +36,7 @@ export class IssueAttachmentFileOwnerService implements FileOwner, OnModuleInit
   /**
    * Файл виден, если видна хоть одна задача, к которой он прикреплён.
    * Видимость проверяем через IIssueRepository.findById, чтобы правило
-   * (reporter/assignee) жило в одном месте. Обычно файл прикреплён к одной задаче.
+   * (reporter/assignee/наблюдатель) жило в одном месте. Обычно файл прикреплён к одной задаче.
    */
   async isVisibleThrough(fileId: string, userId: string): Promise<boolean> {
     const issueIds = await this.attachmentRepository.findIssueIdsByFile(fileId);

src/modules/issue-attachment/application/use-cases/attach-file/attach-file.use-case.ts

@@ -8,6 +8,7 @@ import {
   type IIssueRepository,
 } from '../../../../issue/domain/repositories/issue.repository.interface.js';
 import { IssueNotFoundException } from '../../../../issue/domain/exceptions/issue-not-found.exception.js';
+import { IssueEditForbiddenException } from '../../../../issue/domain/exceptions/issue-edit-forbidden.exception.js';
 import { FileAccessService } from '../../../../file/application/services/file-access.service.js';
 import { IssueAttachment } from '../../../domain/entities/issue-attachment.entity.js';
 import { AttachFileCommand } from './attach-file.command.js';
@@ -15,7 +16,7 @@ import { IssueAttachmentDto } from '../../dto/issue-attachment.dto.js';
 
 /**
  * Прикрепляет к задаче файл, заранее загруженный через POST /files.
- * Прикреплять может любой, кому видна задача (как и править её),
+ * Прикреплять может тот, кто может править задачу (не наблюдатель),
  * но только собственный файл — см. StoredFile.assertOwnedBy.
  */
 @Injectable()
@@ -29,9 +30,13 @@ export class AttachFileUseCase {
   ) {}
 
   async execute(command: AttachFileCommand): Promise<IssueAttachmentDto> {
-    if (!(await this.issueRepository.findById(command.issueId, command.userId))) {
+    const issue = await this.issueRepository.findById(command.issueId, command.userId);
+    if (!issue) {
       throw new IssueNotFoundException(command.issueId);
     }
+    if (!issue.canBeEditedBy(command.userId)) {
+      throw new IssueEditForbiddenException(command.issueId);
+    }
 
     const file = await this.fileAccess.getAttachableFile(command.fileId, command.userId);
     const attachment = await this.attachmentRepository.create(

src/modules/issue-attachment/application/use-cases/detach-file/detach-file.use-case.ts

@@ -8,12 +8,14 @@ import {
   type IIssueRepository,
 } from '../../../../issue/domain/repositories/issue.repository.interface.js';
 import { IssueNotFoundException } from '../../../../issue/domain/exceptions/issue-not-found.exception.js';
+import { IssueEditForbiddenException } from '../../../../issue/domain/exceptions/issue-edit-forbidden.exception.js';
 import { IssueAttachmentNotFoundException } from '../../../domain/exceptions/issue-attachment-not-found.exception.js';
 import { DetachFileCommand } from './detach-file.command.js';
 
 /**
  * Открепляет файл от задачи. Сам файл не удаляется: если он больше
  * ни к чему не прикреплён, его удалит GC file-модуля.
+ * Наблюдателям задачи недоступно — как и её правка.
  */
 @Injectable()
 export class DetachFileUseCase {
@@ -25,9 +27,13 @@ export class DetachFileUseCase {
   ) {}
 
   async execute(command: DetachFileCommand): Promise<void> {
-    if (!(await this.issueRepository.findById(command.issueId, command.userId))) {
+    const issue = await this.issueRepository.findById(command.issueId, command.userId);
+    if (!issue) {
       throw new IssueNotFoundException(command.issueId);
     }
+    if (!issue.canBeEditedBy(command.userId)) {
+      throw new IssueEditForbiddenException(command.issueId);
+    }
 
     if (!(await this.attachmentRepository.delete(command.issueId, command.fileId))) {
       throw new IssueAttachmentNotFoundException(command.issueId, command.fileId);

src/modules/issue-attachment/presentation/controllers/issue-attachment.controller.ts

@@ -23,6 +23,7 @@ import { IssueAttachmentNotFoundException } from '../../domain/exceptions/issue-
 import { IssueNotFoundException } from '../../../issue/domain/exceptions/issue-not-found.exception.js';
 import { FileNotFoundException } from '../../../file/domain/exceptions/file-not-found.exception.js';
 import { FileForbiddenException } from '../../../file/domain/exceptions/file-forbidden.exception.js';
+import { IssueEditForbiddenException } from '../../../issue/domain/exceptions/issue-edit-forbidden.exception.js';
 
 /**
  * Вложения задачи. Сам файл загружается отдельно (POST /files),
@@ -78,7 +79,7 @@ export class IssueAttachmentController {
       ) {
         throw new NotFoundException(error.message);
       }
-      if (error instanceof FileForbiddenException) {
+      if (error instanceof FileForbiddenException || error instanceof IssueEditForbiddenException) {
         throw new ForbiddenException(error.message);
       }
       throw error;

src/modules/issue-type/application/use-cases/list-issue-types/list-issue-types.use-case.ts

@@ -0,0 +1,9 @@
+import { Injectable } from '@nestjs/common';
+import { ISSUE_TYPES } from '../../../../issue/domain/value-objects/issue-type.vo.js';
+
+@Injectable()
+export class ListIssueTypesUseCase {
+  execute(): typeof ISSUE_TYPES {
+    return ISSUE_TYPES;
+  }
+}

src/modules/issue-type/issue-type.module.ts

@@ -0,0 +1,10 @@
+import { Module } from '@nestjs/common';
+import { IssueTypeController } from './presentation/controllers/issue-type.controller.js';
+import { IssueTypeResolver } from './presentation/resolvers/issue-type.resolver.js';
+import { ListIssueTypesUseCase } from './application/use-cases/list-issue-types/list-issue-types.use-case.js';
+
+@Module({
+  controllers: [IssueTypeController],
+  providers: [ListIssueTypesUseCase, IssueTypeResolver],
+})
+export class IssueTypeModule {}

src/modules/issue-type/presentation/controllers/issue-type.controller.ts

@@ -0,0 +1,13 @@
+import { Controller, Get } from '@nestjs/common';
+import { ListIssueTypesUseCase } from '../../application/use-cases/list-issue-types/list-issue-types.use-case.js';
+import { ISSUE_TYPES } from '../../../issue/domain/value-objects/issue-type.vo.js';
+
+@Controller('issue-types')
+export class IssueTypeController {
+  constructor(private readonly listIssueTypesUseCase: ListIssueTypesUseCase) {}
+
+  @Get()
+  list(): typeof ISSUE_TYPES {
+    return this.listIssueTypesUseCase.execute();
+  }
+}

src/modules/issue-type/presentation/graphql/issue-type-definition.type.ts

@@ -0,0 +1,14 @@
+import { Field, ObjectType } from '@nestjs/graphql';
+
+/** Не `IssueType` — это имя занято value-объектом типа задачи */
+@ObjectType('IssueTypeDefinition')
+export class IssueTypeDefinitionType {
+  @Field()
+  name: string;
+
+  @Field()
+  alias: string;
+
+  @Field()
+  color: string;
+}

src/modules/issue-type/presentation/resolvers/issue-type.resolver.ts

@@ -0,0 +1,14 @@
+import { Query, Resolver } from '@nestjs/graphql';
+import { ListIssueTypesUseCase } from '../../application/use-cases/list-issue-types/list-issue-types.use-case.js';
+import { ISSUE_TYPES } from '../../../issue/domain/value-objects/issue-type.vo.js';
+import { IssueTypeDefinitionType } from '../graphql/issue-type-definition.type.js';
+
+@Resolver()
+export class IssueTypeResolver {
+  constructor(private readonly listIssueTypesUseCase: ListIssueTypesUseCase) {}
+
+  @Query(() => [IssueTypeDefinitionType], { name: 'issueTypes' })
+  list(): typeof ISSUE_TYPES {
+    return this.listIssueTypesUseCase.execute();
+  }
+}

src/modules/issue/application/dto/calendar-issues.dto.ts

@@ -0,0 +1,7 @@
+import { IssueWithUsersDto } from './issue-with-users.dto.js';
+
+export class CalendarIssuesDto {
+  list: IssueWithUsersDto[];
+  /** В диапазоне задач больше, чем вернули — клиенту стоит сузить фильтр */
+  truncated: boolean;
+}

src/modules/issue/application/dto/issue-tag.dto.ts

@@ -0,0 +1,6 @@
+/** Тег задачи — из справочника проекта */
+export class IssueTagDto {
+  id: string;
+  name: string;
+  color: string;
+}

src/modules/issue/application/dto/issue-with-users.dto.ts

@@ -1,3 +1,4 @@
+import { IssueTagDto } from './issue-tag.dto.js';
 import { UserDto } from '../../../user/application/dto/user.dto.js';
 
 export class IssueWithUsersDto {
@@ -7,10 +8,15 @@ export class IssueWithUsersDto {
   content: string | null;
   status: string;
   priority: number;
+  type: string;
   assigneeId: string | null;
   reporterId: string | null;
   assignee: UserDto | null;
   reporter: UserDto | null;
+  observerIds: string[];
+  /** Удалённые пользователи сюда не попадают */
+  observers: UserDto[];
+  tags: IssueTagDto[];
   projectId: string;
   dueDate: Date | null;
   createdAt: Date;

src/modules/issue/application/dto/issue.dto.ts

@@ -1,3 +1,5 @@
+import { IssueTagDto } from './issue-tag.dto.js';
+
 export class IssueDto {
   id: number;
   key: string;
@@ -5,8 +7,11 @@ export class IssueDto {
   content: string | null;
   status: string;
   priority: number;
+  type: string;
   assigneeId: string | null;
   reporterId: string | null;
+  observerIds: string[];
+  tags: IssueTagDto[];
   projectId: string;
   dueDate: Date | null;
   createdAt: Date;

src/modules/issue/application/mappers/issue-application.mapper.ts

@@ -2,8 +2,15 @@ import { Issue } from '../../domain/entities/issue.entity.js';
 import { IssueDto } from '../dto/issue.dto.js';
 import { IssueWithUsersDto } from '../dto/issue-with-users.dto.js';
 import { UserDto } from '../../../user/application/dto/user.dto.js';
+import { Tag } from '../../../tag/domain/entities/tag.entity.js';
+import type { IssueTagRef } from '../../domain/value-objects/issue-tags.vo.js';
 
 export class IssueApplicationMapper {
+  /** Тег справочника (уже сохранённый) → тег задачи */
+  static toTagRef(tag: Tag): IssueTagRef {
+    return { id: tag.id as string, name: tag.name, color: tag.color };
+  }
+
   static toDto(issue: Issue): IssueDto {
     return {
       id: issue.id as number,
@@ -12,8 +19,11 @@ export class IssueApplicationMapper {
       content: issue.content,
       status: issue.status,
       priority: issue.priority,
+      type: issue.type,
       assigneeId: issue.assignee,
       reporterId: issue.reporter,
+      observerIds: [...issue.observers],
+      tags: issue.tags.map((tag) => ({ ...tag })),
       projectId: issue.projectId,
       dueDate: issue.dueDate,
       createdAt: issue.createdAt,
@@ -21,7 +31,7 @@ export class IssueApplicationMapper {
     };
   }
 
-  /** Раскрывает assignee/reporter в полноценных пользователей (см. GetIssueUseCase) */
+  /** Раскрывает assignee/reporter/наблюдателей в полноценных пользователей (см. GetIssueUseCase) */
   static toDtoWithUsers(issue: Issue, usersById: ReadonlyMap<string, UserDto>): IssueWithUsersDto {
     return {
       id: issue.id as number,
@@ -30,10 +40,14 @@ export class IssueApplicationMapper {
       content: issue.content,
       status: issue.status,
       priority: issue.priority,
+      type: issue.type,
       assigneeId: issue.assignee,
       reporterId: issue.reporter,
       assignee: issue.assignee ? (usersById.get(issue.assignee) ?? null) : null,
       reporter: issue.reporter ? (usersById.get(issue.reporter) ?? null) : null,
+      observerIds: [...issue.observers],
+      observers: issue.observers.flatMap((id) => usersById.get(id) ?? []),
+      tags: issue.tags.map((tag) => ({ ...tag })),
       projectId: issue.projectId,
       dueDate: issue.dueDate,
       createdAt: issue.createdAt,

src/modules/issue/application/services/issue-assignment-notifier.service.ts

@@ -0,0 +1,48 @@
+import { Injectable } from '@nestjs/common';
+import { NotificationsService } from '../../../notification/application/services/notifications.service.js';
+import { IssueAssignedEvent } from '../../domain/events/issue-assigned.event.js';
+import { IssueObserverAddedEvent } from '../../domain/events/issue-observer-added.event.js';
+import type { Issue } from '../../domain/entities/issue.entity.js';
+
+/**
+ * Уведомляет нового исполнителя задачи (в т.ч. при самоназначении)
+ * и новых наблюдателей по всем включённым у них каналам.
+ */
+@Injectable()
+export class IssueAssignmentNotifierService {
+  constructor(private readonly notificationsService: NotificationsService) {}
+
+  notify(issue: Issue, domainEvents: unknown[]): void {
+    this.notifyAssignee(issue, domainEvents);
+    this.notifyObservers(issue, domainEvents);
+  }
+
+  private notifyAssignee(issue: Issue, domainEvents: unknown[]): void {
+    const assigned = domainEvents.findLast((event) => event instanceof IssueAssignedEvent);
+    // Последнее назначение могло быть отменено снятием исполнителя в той же операции
+    if (!assigned || assigned.assignee !== issue.assignee) return;
+
+    this.notificationsService.notify({
+      userId: assigned.assignee,
+      subject: `You have been assigned to ${issue.key}`,
+      content: issue.title,
+    });
+  }
+
+  private notifyObservers(issue: Issue, domainEvents: unknown[]): void {
+    const added = new Set(
+      domainEvents.filter((event) => event instanceof IssueObserverAddedEvent).map((event) => event.observer),
+    );
+
+    // Наблюдатель мог быть снят или назначен исполнителем в той же операции
+    for (const userId of added) {
+      if (!issue.observers.includes(userId)) continue;
+
+      this.notificationsService.notify({
+        userId,
+        subject: `You are now observing ${issue.key}`,
+        content: issue.title,
+      });
+    }
+  }
+}

src/modules/issue/application/services/issue-participants.service.ts

@@ -0,0 +1,44 @@
+import { Inject, Injectable } from '@nestjs/common';
+import {
+  PROJECT_REPOSITORY,
+  type IProjectRepository,
+} from '../../../project/domain/repositories/project.repository.interface.js';
+import { GetUsersUseCase } from '../../../user/application/use-cases/get-users/get-users.use-case.js';
+import { GetUsersQuery } from '../../../user/application/use-cases/get-users/get-users.query.js';
+import type { Issue } from '../../domain/entities/issue.entity.js';
+import { IssueObserverNotFoundException } from '../../domain/exceptions/issue-observer-not-found.exception.js';
+
+/** Участники задачи (assignee и наблюдатели) за пределами самой сущности */
+@Injectable()
+export class IssueParticipantsService {
+  constructor(
+    @Inject(PROJECT_REPOSITORY)
+    private readonly projectRepository: IProjectRepository,
+    private readonly getUsersUseCase: GetUsersUseCase,
+  ) {}
+
+  /** Проверяет до сохранения, что новые наблюдатели существуют — иначе упадёт внешний ключ */
+  async ensureObserversExist(userIds: string[]): Promise<void> {
+    if (userIds.length === 0) return;
+
+    const users = await this.getUsersUseCase.execute(new GetUsersQuery(userIds));
+    const found = new Set(users.map((user) => user.id));
+    const missing = userIds.filter((id) => !found.has(id));
+    if (missing.length > 0) {
+      throw new IssueObserverNotFoundException(missing);
+    }
+  }
+
+  /**
+   * Исполнитель и наблюдатели становятся участниками проекта, чтобы видеть его в списке.
+   * Наблюдатель — с ролью OBSERVER: задачи в проекте он создавать не может.
+   */
+  async addToProject(issue: Issue): Promise<void> {
+    if (issue.assignee) {
+      await this.projectRepository.addMember(issue.projectId, issue.assignee, 'MEMBER');
+    }
+    for (const userId of issue.observers) {
+      await this.projectRepository.addMember(issue.projectId, userId, 'OBSERVER');
+    }
+  }
+}

src/modules/issue/application/services/issue-user-expander.service.spec.ts

@@ -24,6 +24,7 @@ const buildIssue = (overrides: Partial<{ assignee: string | null; reporter: stri
     content: null,
     status: 'OPEN',
     priority: 0,
+    type: 'TASK',
     assignee: 'assignee' in overrides ? (overrides.assignee ?? null) : 'user-2',
     reporter: overrides.reporter ?? 'user-1',
     projectId: 'project-1',

src/modules/issue/application/services/issue-user-expander.service.ts

@@ -5,7 +5,7 @@ import { IssueApplicationMapper } from '../mappers/issue-application.mapper.js';
 import { GetUsersUseCase } from '../../../user/application/use-cases/get-users/get-users.use-case.js';
 import { GetUsersQuery } from '../../../user/application/use-cases/get-users/get-users.query.js';
 
-/** Раскрывает assignee/reporter задачи (или списка задач) в полноценных пользователей */
+/** Раскрывает assignee/reporter/наблюдателей задачи (или списка задач) в полноценных пользователей */
 @Injectable()
 export class IssueUserExpanderService {
   constructor(private readonly getUsersUseCase: GetUsersUseCase) {}
@@ -19,7 +19,11 @@ export class IssueUserExpanderService {
     if (issues.length === 0) return [];
 
     const userIds = [
-      ...new Set(issues.flatMap((issue) => [issue.reporter, issue.assignee]).filter((id): id is string => Boolean(id))),
+      ...new Set(
+        issues
+          .flatMap((issue) => [issue.reporter, issue.assignee, ...issue.observers])
+          .filter((id): id is string => Boolean(id)),
+      ),
     ];
     const users = await this.getUsersUseCase.execute(new GetUsersQuery(userIds));
     const usersById = new Map(users.map((user) => [user.id, user]));

src/modules/issue/application/use-cases/create-issue/create-issue.command.ts

@@ -8,5 +8,9 @@ export class CreateIssueCommand {
     public readonly priority?: number,
     public readonly assignee?: string,
     public readonly dueDate?: Date,
+    public readonly type?: string,
+    public readonly observers?: string[],
+    /** Имена тегов; отсутствующие в справочнике проекта создаются */
+    public readonly tags?: string[],
   ) {}
 }

src/modules/issue/application/use-cases/create-issue/create-issue.use-case.spec.ts

@@ -1,5 +1,7 @@
 import { beforeEach, describe, expect, it, vi } from 'vitest';
 import type { IIssueRepository } from '../../../domain/repositories/issue.repository.interface.js';
+import type { ITagRepository } from '../../../../tag/domain/repositories/tag.repository.interface.js';
+import { buildTag, mockTagRepository } from '../../../../tag/application/use-cases/test-helpers.js';
 import type { IProjectRepository } from '../../../../project/domain/repositories/project.repository.interface.js';
 import { Issue } from '../../../domain/entities/issue.entity.js';
 import { CreateIssueUseCase } from './create-issue.use-case.js';
@@ -7,12 +9,22 @@ import { CreateIssueCommand } from './create-issue.command.js';
 import { IssueEventsService } from '../../services/issue-events.service.js';
 import { IssueUserExpanderService } from '../../services/issue-user-expander.service.js';
 import { IssueApplicationMapper } from '../../mappers/issue-application.mapper.js';
+import { IssueAssignmentNotifierService } from '../../services/issue-assignment-notifier.service.js';
+import type { NotificationsService } from '../../../../notification/application/services/notifications.service.js';
+import { IssueParticipantsService } from '../../services/issue-participants.service.js';
+import type { GetUsersUseCase } from '../../../../user/application/use-cases/get-users/get-users.use-case.js';
+import type { GetUsersQuery } from '../../../../user/application/use-cases/get-users/get-users.query.js';
+import { IssueProjectNotFoundException } from '../../../domain/exceptions/issue-project-not-found.exception.js';
+import { IssueProjectForbiddenException } from '../../../domain/exceptions/issue-project-forbidden.exception.js';
 
 describe('CreateIssueUseCase', () => {
   let repository: IIssueRepository;
   let projectRepository: IProjectRepository;
   let issueEventsService: IssueEventsService;
   let issueUserExpander: IssueUserExpanderService;
+  let notificationsService: NotificationsService;
+  let getUsersUseCase: GetUsersUseCase;
+  let tagRepository: ITagRepository;
   let useCase: CreateIssueUseCase;
 
   beforeEach(() => {
@@ -20,6 +32,7 @@ describe('CreateIssueUseCase', () => {
       findById: vi.fn(),
       findByCKey: vi.fn(),
       findAll: vi.fn(),
+      findByDueDateRange: vi.fn(),
       countByStatus: vi.fn(),
       create: vi.fn(),
       update: vi.fn(),
@@ -31,6 +44,7 @@ describe('CreateIssueUseCase', () => {
       create: vi.fn(),
       update: vi.fn(),
       delete: vi.fn(),
+      findRole: vi.fn(async () => 'MEMBER' as const),
       addMember: vi.fn(),
     };
     issueEventsService = new IssueEventsService();
@@ -41,7 +55,20 @@ describe('CreateIssueUseCase', () => {
         reporter: null,
       })),
     } as unknown as IssueUserExpanderService;
-    useCase = new CreateIssueUseCase(repository, projectRepository, issueEventsService, issueUserExpander);
+    notificationsService = { notify: vi.fn() } as unknown as NotificationsService;
+    getUsersUseCase = {
+      execute: vi.fn(async (query: GetUsersQuery) => query.ids.filter((id) => id !== 'ghost').map((id) => ({ id }))),
+    } as unknown as GetUsersUseCase;
+    tagRepository = mockTagRepository([buildTag({ id: 'tag-1', name: 'backend', color: 'primary' })]);
+    useCase = new CreateIssueUseCase(
+      repository,
+      projectRepository,
+      tagRepository,
+      issueEventsService,
+      issueUserExpander,
+      new IssueAssignmentNotifierService(notificationsService),
+      new IssueParticipantsService(projectRepository, getUsersUseCase),
+    );
   });
 
   it('persists a new issue and returns it as a DTO with the DB-assigned id', async () => {
@@ -53,6 +80,7 @@ describe('CreateIssueUseCase', () => {
         content: issue.content,
         status: issue.status,
         priority: issue.priority,
+        type: issue.type,
         assignee: issue.assignee,
         reporter: issue.reporter,
         projectId: issue.projectId,
@@ -71,6 +99,7 @@ describe('CreateIssueUseCase', () => {
       title: 'Fix login bug',
       status: 'OPEN',
       priority: 0,
+      type: 'TASK',
       reporterId: 'user-1',
     });
   });
@@ -102,6 +131,7 @@ describe('CreateIssueUseCase', () => {
         content: issue.content,
         status: issue.status,
         priority: issue.priority,
+        type: issue.type,
         assignee: issue.assignee,
         reporter: issue.reporter,
         projectId: issue.projectId,
@@ -118,4 +148,158 @@ describe('CreateIssueUseCase', () => {
 
     expect(received).toEqual([dto]);
   });
+
+  it('notifies the assignee of a new issue', async () => {
+    vi.mocked(repository.create).mockImplementation(async (issue) => issue);
+
+    await useCase.execute(
+      new CreateIssueCommand('ISSUE-2', 'Improve onboarding', 'user-1', 'project-1', undefined, undefined, 'user-2'),
+    );
+
+    expect(notificationsService.notify).toHaveBeenCalledWith({
+      userId: 'user-2',
+      subject: 'You have been assigned to ISSUE-2',
+      content: 'Improve onboarding',
+    });
+  });
+
+  it('notifies the reporter who assigns the issue to themselves', async () => {
+    vi.mocked(repository.create).mockImplementation(async (issue) => issue);
+
+    await useCase.execute(
+      new CreateIssueCommand('ISSUE-2', 'Improve onboarding', 'user-1', 'project-1', undefined, undefined, 'user-1'),
+    );
+
+    expect(notificationsService.notify).toHaveBeenCalledWith(expect.objectContaining({ userId: 'user-1' }));
+  });
+
+  it('does not notify when the issue is created unassigned', async () => {
+    vi.mocked(repository.create).mockImplementation(async (issue) => issue);
+
+    await useCase.execute(new CreateIssueCommand('ISSUE-3', 'Improve onboarding', 'user-1', 'project-1'));
+
+    expect(notificationsService.notify).not.toHaveBeenCalled();
+  });
+
+  it('creates a TASK by default and accepts an explicit type', async () => {
+    vi.mocked(repository.create).mockImplementation(async (issue) => issue);
+
+    const task = await useCase.execute(new CreateIssueCommand('ISSUE-4', 'Something', 'user-1', 'project-1'));
+    const bug = await useCase.execute(
+      new CreateIssueCommand(
+        'ISSUE-5',
+        'Crash on start',
+        'user-1',
+        'project-1',
+        undefined,
+        undefined,
+        undefined,
+        undefined,
+        'BUG',
+      ),
+    );
+
+    expect(task.type).toBe('TASK');
+    expect(bug.type).toBe('BUG');
+  });
+
+  it('assigns tags by name, creating the missing ones in the project', async () => {
+    vi.mocked(repository.create).mockImplementation(async (issue) => issue);
+
+    const dto = await useCase.execute(
+      new CreateIssueCommand(
+        'ISSUE-6',
+        'Something',
+        'user-1',
+        'project-1',
+        undefined,
+        undefined,
+        undefined,
+        undefined,
+        undefined,
+        undefined,
+        ['ui', 'Backend', 'UI'],
+      ),
+    );
+
+    expect(tagRepository.findOrCreateByNames).toHaveBeenCalledWith('project-1', ['ui', 'Backend', 'UI']);
+    // Существующий тег берётся в написании справочника
+    expect(dto.tags).toEqual([
+      { id: 'tag-1', name: 'backend', color: 'primary' },
+      { id: 'tag-ui', name: 'ui', color: 'default' },
+    ]);
+  });
+
+  it('does not create tags in a project the reporter cannot create issues in', async () => {
+    vi.mocked(projectRepository.findRole).mockResolvedValue('OBSERVER');
+
+    await expect(
+      useCase.execute(
+        new CreateIssueCommand(
+          'ISSUE-7',
+          'Something',
+          'user-1',
+          'project-1',
+          undefined,
+          undefined,
+          undefined,
+          undefined,
+          undefined,
+          undefined,
+          ['ui'],
+        ),
+      ),
+    ).rejects.toThrow();
+
+    expect(tagRepository.findOrCreateByNames).not.toHaveBeenCalled();
+  });
+
+  it('checks project access on behalf of the reporter', async () => {
+    vi.mocked(repository.create).mockImplementation(async (issue) => issue);
+
+    await useCase.execute(new CreateIssueCommand('ISSUE-1', 'Fix login bug', 'user-1', 'project-1'));
+
+    expect(projectRepository.findRole).toHaveBeenCalledWith('project-1', 'user-1');
+  });
+
+  it('refuses to create an issue in a project the reporter has no access to', async () => {
+    vi.mocked(projectRepository.findRole).mockResolvedValue(null);
+
+    await expect(
+      useCase.execute(new CreateIssueCommand('ISSUE-1', 'Fix login bug', 'user-9', 'project-1')),
+    ).rejects.toBeInstanceOf(IssueProjectNotFoundException);
+    expect(repository.create).not.toHaveBeenCalled();
+    expect(projectRepository.addMember).not.toHaveBeenCalled();
+  });
+
+  it('forbids a project observer from creating issues', async () => {
+    vi.mocked(projectRepository.findRole).mockResolvedValue('OBSERVER');
+
+    await expect(
+      useCase.execute(new CreateIssueCommand('ISSUE-1', 'Fix login bug', 'user-5', 'project-1')),
+    ).rejects.toBeInstanceOf(IssueProjectForbiddenException);
+    expect(repository.create).not.toHaveBeenCalled();
+  });
+
+  it('adds the assignee to the project as a member and observers as observers', async () => {
+    vi.mocked(repository.create).mockImplementation(async (issue) => issue);
+
+    await useCase.execute(
+      new CreateIssueCommand(
+        'ISSUE-1',
+        'Fix login bug',
+        'user-1',
+        'project-1',
+        undefined,
+        undefined,
+        'user-2',
+        undefined,
+        undefined,
+        ['user-3'],
+      ),
+    );
+
+    expect(projectRepository.addMember).toHaveBeenCalledWith('project-1', 'user-2', 'MEMBER');
+    expect(projectRepository.addMember).toHaveBeenCalledWith('project-1', 'user-3', 'OBSERVER');
+  });
 });

src/modules/issue/application/use-cases/create-issue/create-issue.use-case.ts

@@ -5,11 +5,17 @@ import {
   PROJECT_REPOSITORY,
   type IProjectRepository,
 } from '../../../../project/domain/repositories/project.repository.interface.js';
+import { IssueProjectNotFoundException } from '../../../domain/exceptions/issue-project-not-found.exception.js';
+import { IssueProjectForbiddenException } from '../../../domain/exceptions/issue-project-forbidden.exception.js';
 import { CreateIssueCommand } from './create-issue.command.js';
+import { IssueApplicationMapper } from '../../mappers/issue-application.mapper.js';
 import { IssueWithUsersDto } from '../../dto/issue-with-users.dto.js';
 import { IssueEventsService } from '../../services/issue-events.service.js';
 import { IssueUserExpanderService } from '../../services/issue-user-expander.service.js';
+import { IssueAssignmentNotifierService } from '../../services/issue-assignment-notifier.service.js';
+import { IssueParticipantsService } from '../../services/issue-participants.service.js';
 import { IssueCreatedEvent } from '../../../domain/events/issue-created.event.js';
+import { TAG_REPOSITORY, type ITagRepository } from '../../../../tag/domain/repositories/tag.repository.interface.js';
 
 @Injectable()
 export class CreateIssueUseCase {
@@ -18,30 +24,52 @@ export class CreateIssueUseCase {
     private readonly issueRepository: IIssueRepository,
     @Inject(PROJECT_REPOSITORY)
     private readonly projectRepository: IProjectRepository,
+    @Inject(TAG_REPOSITORY)
+    private readonly tagRepository: ITagRepository,
     private readonly issueEventsService: IssueEventsService,
     private readonly issueUserExpander: IssueUserExpanderService,
+    private readonly issueAssignmentNotifier: IssueAssignmentNotifierService,
+    private readonly issueParticipants: IssueParticipantsService,
   ) {}
 
   async execute(command: CreateIssueCommand): Promise<IssueWithUsersDto> {
+    // Создавать задачи может владелец или участник проекта, но не наблюдатель.
+    // Чужой проект неотличим от несуществующего — 404, как и раньше.
+    const role = await this.projectRepository.findRole(command.projectId, command.reporter);
+    if (!role) {
+      throw new IssueProjectNotFoundException(command.projectId);
+    }
+    if (role === 'OBSERVER') {
+      throw new IssueProjectForbiddenException(command.projectId);
+    }
+
+    // Теги создаются в справочнике только после проверки доступа к проекту
+    const tags = command.tags?.length
+      ? await this.tagRepository.findOrCreateByNames(command.projectId, command.tags)
+      : [];
+
     const draft = Issue.create({
       key: command.key,
       title: command.title,
       content: command.content,
       priority: command.priority,
+      type: command.type,
       assignee: command.assignee,
       reporter: command.reporter,
+      observers: command.observers,
+      tags: tags.map(IssueApplicationMapper.toTagRef),
       projectId: command.projectId,
       dueDate: command.dueDate,
     });
 
+    await this.issueParticipants.ensureObserversExist([...draft.observers]);
     const issue = await this.issueRepository.create(draft);
     const dto = await this.issueUserExpander.expand(issue);
 
-    if (issue.assignee) {
+    await this.issueParticipants.addToProject(issue);
-      await this.projectRepository.addMember(issue.projectId, issue.assignee);
-    }
 
     const domainEvents = draft.pullDomainEvents();
+    this.issueAssignmentNotifier.notify(issue, domainEvents);
     if (domainEvents.some((event) => event instanceof IssueCreatedEvent)) {
       this.issueEventsService.emitIssueCreated(dto);
     }

src/modules/issue/application/use-cases/delete-issue/delete-issue.use-case.spec.ts

@@ -2,6 +2,7 @@ import { beforeEach, describe, expect, it, vi } from 'vitest';
 import type { IIssueRepository } from '../../../domain/repositories/issue.repository.interface.js';
 import { Issue } from '../../../domain/entities/issue.entity.js';
 import { IssueNotFoundException } from '../../../domain/exceptions/issue-not-found.exception.js';
+import { IssueEditForbiddenException } from '../../../domain/exceptions/issue-edit-forbidden.exception.js';
 import { DeleteIssueUseCase } from './delete-issue.use-case.js';
 import { DeleteIssueCommand } from './delete-issue.command.js';
 import { IssueEventsService } from '../../services/issue-events.service.js';
@@ -14,8 +15,10 @@ const buildIssue = () =>
     content: null,
     status: 'OPEN',
     priority: 0,
+    type: 'TASK',
     assignee: null,
     reporter: 'user-1',
+    observers: ['user-5'],
     projectId: 'project-1',
     dueDate: null,
     createdAt: new Date(),
@@ -32,6 +35,7 @@ describe('DeleteIssueUseCase', () => {
       findById: vi.fn(),
       findByCKey: vi.fn(),
       findAll: vi.fn(),
+      findByDueDateRange: vi.fn(),
       countByStatus: vi.fn(),
       create: vi.fn(),
       update: vi.fn(),
@@ -71,4 +75,13 @@ describe('DeleteIssueUseCase', () => {
       }),
     ]);
   });
+
+  it('forbids an observer from deleting the issue', async () => {
+    vi.mocked(repository.findById).mockResolvedValue(buildIssue());
+
+    await expect(useCase.execute(new DeleteIssueCommand(1, 'user-5'))).rejects.toBeInstanceOf(
+      IssueEditForbiddenException,
+    );
+    expect(repository.delete).not.toHaveBeenCalled();
+  });
 });

src/modules/issue/application/use-cases/delete-issue/delete-issue.use-case.ts

@@ -1,6 +1,7 @@
 import { Inject, Injectable } from '@nestjs/common';
 import { ISSUE_REPOSITORY, type IIssueRepository } from '../../../domain/repositories/issue.repository.interface.js';
 import { IssueNotFoundException } from '../../../domain/exceptions/issue-not-found.exception.js';
+import { IssueEditForbiddenException } from '../../../domain/exceptions/issue-edit-forbidden.exception.js';
 import { DeleteIssueCommand } from './delete-issue.command.js';
 import { IssueApplicationMapper } from '../../mappers/issue-application.mapper.js';
 import { IssueEventsService } from '../../services/issue-events.service.js';
@@ -20,6 +21,10 @@ export class DeleteIssueUseCase {
       throw new IssueNotFoundException(command.id);
     }
 
+    if (!issue.canBeEditedBy(command.userId)) {
+      throw new IssueEditForbiddenException(command.id);
+    }
+
     await this.issueRepository.delete(command.id);
 
     this.issueEventsService.emitIssueDeleted(IssueApplicationMapper.toDto(issue));

src/modules/issue/application/use-cases/get-issue-by-ckey/get-issue-by-ckey.use-case.spec.ts

@@ -15,6 +15,7 @@ const buildIssue = () =>
     content: null,
     status: 'OPEN',
     priority: 0,
+    type: 'TASK',
     assignee: 'user-2',
     reporter: 'user-1',
     projectId: 'project-1',
@@ -33,6 +34,7 @@ describe('GetIssueByCkeyUseCase', () => {
       findById: vi.fn(),
       findByCKey: vi.fn(),
       findAll: vi.fn(),
+      findByDueDateRange: vi.fn(),
       countByStatus: vi.fn(),
       create: vi.fn(),
       update: vi.fn(),

src/modules/issue/application/use-cases/get-issue-stats/get-issue-stats.use-case.spec.ts

@@ -11,6 +11,7 @@ describe('GetIssueStatsUseCase', () => {
       findById: vi.fn(),
       findByCKey: vi.fn(),
       findAll: vi.fn(),
+      findByDueDateRange: vi.fn(),
       countByStatus: vi.fn(),
       create: vi.fn(),
       update: vi.fn(),

src/modules/issue/application/use-cases/get-issue/get-issue.use-case.spec.ts

@@ -15,6 +15,7 @@ const buildIssue = () =>
     content: null,
     status: 'OPEN',
     priority: 0,
+    type: 'TASK',
     assignee: 'user-2',
     reporter: 'user-1',
     projectId: 'project-1',
@@ -33,6 +34,7 @@ describe('GetIssueUseCase', () => {
       findById: vi.fn(),
       findByCKey: vi.fn(),
       findAll: vi.fn(),
+      findByDueDateRange: vi.fn(),
       countByStatus: vi.fn(),
       create: vi.fn(),
       update: vi.fn(),

src/modules/issue/application/use-cases/list-calendar-issues/list-calendar-issues.query.ts

@@ -0,0 +1,10 @@
+export class ListCalendarIssuesQuery {
+  constructor(
+    public readonly userId: string,
+    public readonly from: Date,
+    public readonly to: Date,
+    public readonly projectId?: string,
+    public readonly status?: string[],
+    public readonly assigneeId?: string,
+  ) {}
+}

src/modules/issue/application/use-cases/list-calendar-issues/list-calendar-issues.use-case.spec.ts

@@ -0,0 +1,89 @@
+import { beforeEach, describe, expect, it, vi } from 'vitest';
+import type { IIssueRepository } from '../../../domain/repositories/issue.repository.interface.js';
+import { Issue } from '../../../domain/entities/issue.entity.js';
+import { InvalidCalendarRangeException } from '../../../domain/exceptions/invalid-calendar-range.exception.js';
+import { ListCalendarIssuesUseCase } from './list-calendar-issues.use-case.js';
+import { ListCalendarIssuesQuery } from './list-calendar-issues.query.js';
+import type { IssueUserExpanderService } from '../../services/issue-user-expander.service.js';
+import type { IssueWithUsersDto } from '../../dto/issue-with-users.dto.js';
+
+const FROM = new Date('2026-09-28T00:00:00+03:00');
+const TO = new Date('2026-11-09T00:00:00+03:00');
+
+const buildIssue = (id: number) =>
+  Issue.reconstitute({
+    id,
+    key: `ISSUE-${id}`,
+    title: `Issue ${id}`,
+    content: null,
+    status: 'OPEN',
+    priority: 0,
+    type: 'TASK',
+    assignee: null,
+    reporter: 'user-1',
+    projectId: 'project-1',
+    dueDate: new Date('2026-10-15T12:00:00Z'),
+    createdAt: new Date(),
+    updatedAt: new Date(),
+  });
+
+describe('ListCalendarIssuesUseCase', () => {
+  let repository: IIssueRepository;
+  let issueUserExpander: IssueUserExpanderService;
+  let useCase: ListCalendarIssuesUseCase;
+
+  beforeEach(() => {
+    repository = {
+      findById: vi.fn(),
+      findByCKey: vi.fn(),
+      findAll: vi.fn(),
+      findByDueDateRange: vi.fn(),
+      countByStatus: vi.fn(),
+      create: vi.fn(),
+      update: vi.fn(),
+      delete: vi.fn(),
+    };
+    issueUserExpander = {
+      expandAll: vi.fn(async (issues: Issue[]) => issues.map((issue) => ({ id: issue.id }) as IssueWithUsersDto)),
+    } as unknown as IssueUserExpanderService;
+    useCase = new ListCalendarIssuesUseCase(repository, issueUserExpander);
+  });
+
+  it('forwards the range and filters, asking for one issue more than the limit', async () => {
+    vi.mocked(repository.findByDueDateRange).mockResolvedValue([buildIssue(1), buildIssue(2)]);
+
+    const result = await useCase.execute(
+      new ListCalendarIssuesQuery('user-1', FROM, TO, 'project-1', ['OPEN'], 'user-2'),
+    );
+
+    expect(repository.findByDueDateRange).toHaveBeenCalledWith({
+      from: FROM,
+      to: TO,
+      limit: ListCalendarIssuesUseCase.MAX_ISSUES + 1,
+      userId: 'user-1',
+      projectId: 'project-1',
+      status: ['OPEN'],
+      assigneeId: 'user-2',
+    });
+    expect(result).toEqual({ list: [{ id: 1 }, { id: 2 }], truncated: false });
+  });
+
+  it('cuts the list to the limit and marks it as truncated', async () => {
+    const issues = Array.from({ length: ListCalendarIssuesUseCase.MAX_ISSUES + 1 }, (_, index) =>
+      buildIssue(index + 1),
+    );
+    vi.mocked(repository.findByDueDateRange).mockResolvedValue(issues);
+
+    const result = await useCase.execute(new ListCalendarIssuesQuery('user-1', FROM, TO));
+
+    expect(result.truncated).toBe(true);
+    expect(result.list).toHaveLength(ListCalendarIssuesUseCase.MAX_ISSUES);
+  });
+
+  it('rejects an invalid range without querying the repository', async () => {
+    await expect(useCase.execute(new ListCalendarIssuesQuery('user-1', TO, FROM))).rejects.toThrow(
+      InvalidCalendarRangeException,
+    );
+    expect(repository.findByDueDateRange).not.toHaveBeenCalled();
+  });
+});

src/modules/issue/application/use-cases/list-calendar-issues/list-calendar-issues.use-case.ts

@@ -0,0 +1,42 @@
+import { Inject, Injectable } from '@nestjs/common';
+import { ISSUE_REPOSITORY, type IIssueRepository } from '../../../domain/repositories/issue.repository.interface.js';
+import { CalendarRange } from '../../../domain/value-objects/calendar-range.vo.js';
+import { CalendarIssuesDto } from '../../dto/calendar-issues.dto.js';
+import { IssueUserExpanderService } from '../../services/issue-user-expander.service.js';
+import { ListCalendarIssuesQuery } from './list-calendar-issues.query.js';
+
+/**
+ * Задачи для календаря: все задачи с dueDate в [from, to) без пагинации,
+ * но не больше MAX_ISSUES — иначе ответ помечается как truncated.
+ * Задачи без dueDate в календарь не попадают.
+ */
+@Injectable()
+export class ListCalendarIssuesUseCase {
+  static readonly MAX_ISSUES = 500;
+
+  constructor(
+    @Inject(ISSUE_REPOSITORY)
+    private readonly issueRepository: IIssueRepository,
+    private readonly issueUserExpander: IssueUserExpanderService,
+  ) {}
+
+  async execute(query: ListCalendarIssuesQuery): Promise<CalendarIssuesDto> {
+    const range = CalendarRange.create({ from: query.from, to: query.to });
+
+    // Берём на одну больше лимита, чтобы узнать, есть ли что-то за ним
+    const issues = await this.issueRepository.findByDueDateRange({
+      from: range.from,
+      to: range.to,
+      limit: ListCalendarIssuesUseCase.MAX_ISSUES + 1,
+      userId: query.userId,
+      projectId: query.projectId,
+      status: query.status,
+      assigneeId: query.assigneeId,
+    });
+
+    const truncated = issues.length > ListCalendarIssuesUseCase.MAX_ISSUES;
+    const list = truncated ? issues.slice(0, ListCalendarIssuesUseCase.MAX_ISSUES) : issues;
+
+    return { list: await this.issueUserExpander.expandAll(list), truncated };
+  }
+}

src/modules/issue/application/use-cases/list-issues/list-issues.query.ts

@@ -1,11 +1,16 @@
+import type { IssueUserRole } from '../../../domain/repositories/issue.repository.interface.js';
+
 export class ListIssuesQuery {
   constructor(
     public readonly limit: number,
     public readonly page: number,
     public readonly userId: string,
     public readonly projectId?: string,
-    public readonly status?: string,
+    public readonly status?: string[],
     public readonly text?: string,
     public readonly assigneeId?: string,
+    public readonly hasDueDate?: boolean,
+    public readonly type?: string[],
+    public readonly role?: IssueUserRole,
   ) {}
 }

src/modules/issue/application/use-cases/list-issues/list-issues.use-case.spec.ts

@@ -14,6 +14,7 @@ const buildIssue = (id: number) =>
     content: null,
     status: 'OPEN',
     priority: 0,
+    type: 'TASK',
     assignee: null,
     reporter: 'user-1',
     projectId: 'project-1',
@@ -32,6 +33,7 @@ describe('ListIssuesUseCase', () => {
       findById: vi.fn(),
       findByCKey: vi.fn(),
       findAll: vi.fn(),
+      findByDueDateRange: vi.fn(),
       countByStatus: vi.fn(),
       create: vi.fn(),
       update: vi.fn(),
@@ -61,6 +63,20 @@ describe('ListIssuesUseCase', () => {
     expect(result.meta).toEqual({ totalCount: 2, page: 1, totalPages: 1 });
   });
 
+  it('forwards the hasDueDate filter', async () => {
+    vi.mocked(repository.findAll).mockResolvedValue({
+      list: [],
+      meta: { totalCount: 0, page: 1, totalPages: 0 },
+    });
+    vi.mocked(issueUserExpander.expandAll).mockResolvedValue([]);
+
+    await useCase.execute(new ListIssuesQuery(20, 1, 'user-1', 'project-1', undefined, undefined, undefined, false));
+
+    expect(repository.findAll).toHaveBeenCalledWith(
+      expect.objectContaining({ projectId: 'project-1', hasDueDate: false }),
+    );
+  });
+
   it('returns an empty array when there are no issues', async () => {
     vi.mocked(repository.findAll).mockResolvedValue({
       list: [],

src/modules/issue/application/use-cases/list-issues/list-issues.use-case.ts

@@ -22,6 +22,9 @@ export class ListIssuesUseCase {
       status: query.status,
       text: query.text,
       assigneeId: query.assigneeId,
+      hasDueDate: query.hasDueDate,
+      type: query.type,
+      role: query.role,
     });
 
     return { list: await this.issueUserExpander.expandAll(list), meta };

src/modules/issue/application/use-cases/unobserve-issue/unobserve-issue.command.ts

@@ -0,0 +1,6 @@
+export class UnobserveIssueCommand {
+  constructor(
+    public readonly id: number,
+    public readonly userId: string,
+  ) {}
+}

src/modules/issue/application/use-cases/unobserve-issue/unobserve-issue.use-case.spec.ts

@@ -0,0 +1,75 @@
+import { beforeEach, describe, expect, it, vi } from 'vitest';
+import type { IIssueRepository } from '../../../domain/repositories/issue.repository.interface.js';
+import { Issue } from '../../../domain/entities/issue.entity.js';
+import { IssueNotFoundException } from '../../../domain/exceptions/issue-not-found.exception.js';
+import { IssueEventsService } from '../../services/issue-events.service.js';
+import { UnobserveIssueUseCase } from './unobserve-issue.use-case.js';
+import { UnobserveIssueCommand } from './unobserve-issue.command.js';
+
+const buildIssue = () =>
+  Issue.reconstitute({
+    id: 1,
+    key: 'ISSUE-1',
+    title: 'Title',
+    content: null,
+    status: 'OPEN',
+    priority: 0,
+    type: 'TASK',
+    assignee: null,
+    reporter: 'user-1',
+    observers: ['user-5', 'user-6'],
+    projectId: 'project-1',
+    dueDate: null,
+    createdAt: new Date(),
+    updatedAt: new Date(),
+  });
+
+describe('UnobserveIssueUseCase', () => {
+  let repository: IIssueRepository;
+  let issueEventsService: IssueEventsService;
+  let useCase: UnobserveIssueUseCase;
+
+  beforeEach(() => {
+    repository = {
+      findById: vi.fn(),
+      findByCKey: vi.fn(),
+      findAll: vi.fn(),
+      findByDueDateRange: vi.fn(),
+      countByStatus: vi.fn(),
+      create: vi.fn(),
+      update: vi.fn(),
+      delete: vi.fn(),
+    };
+    issueEventsService = new IssueEventsService();
+    useCase = new UnobserveIssueUseCase(repository, issueEventsService);
+  });
+
+  it('removes the current user from observers on behalf of themselves', async () => {
+    vi.mocked(repository.findById).mockResolvedValue(buildIssue());
+    const received: unknown[] = [];
+    issueEventsService.onIssueUpdated().subscribe((issue) => received.push(issue));
+
+    await useCase.execute(new UnobserveIssueCommand(1, 'user-5'));
+
+    const [saved, actorId] = vi.mocked(repository.update).mock.calls[0]!;
+    expect(saved.observers).toEqual(['user-6']);
+    expect(actorId).toBe('user-5');
+    expect(received).toEqual([expect.objectContaining({ observerIds: ['user-6'] })]);
+  });
+
+  it('does nothing for a user who is not an observer', async () => {
+    vi.mocked(repository.findById).mockResolvedValue(buildIssue());
+
+    await useCase.execute(new UnobserveIssueCommand(1, 'user-1'));
+
+    expect(repository.update).not.toHaveBeenCalled();
+  });
+
+  it('throws when the issue is not visible', async () => {
+    vi.mocked(repository.findById).mockResolvedValue(null);
+
+    await expect(useCase.execute(new UnobserveIssueCommand(1, 'user-9'))).rejects.toBeInstanceOf(
+      IssueNotFoundException,
+    );
+  });
+});

src/modules/issue/application/use-cases/unobserve-issue/unobserve-issue.use-case.ts

@@ -0,0 +1,35 @@
+import { Inject, Injectable } from '@nestjs/common';
+import { ISSUE_REPOSITORY, type IIssueRepository } from '../../../domain/repositories/issue.repository.interface.js';
+import { IssueNotFoundException } from '../../../domain/exceptions/issue-not-found.exception.js';
+import { IssueEventsService } from '../../services/issue-events.service.js';
+import { IssueApplicationMapper } from '../../mappers/issue-application.mapper.js';
+import { UnobserveIssueCommand } from './unobserve-issue.command.js';
+
+/**
+ * Наблюдатель сам отписывается от задачи. Редактировать задачу он не может,
+ * поэтому это отдельная операция, а не часть UpdateIssueUseCase.
+ * Повторный вызов (или вызов не наблюдателем) ничего не меняет.
+ */
+@Injectable()
+export class UnobserveIssueUseCase {
+  constructor(
+    @Inject(ISSUE_REPOSITORY)
+    private readonly issueRepository: IIssueRepository,
+    private readonly issueEventsService: IssueEventsService,
+  ) {}
+
+  async execute(command: UnobserveIssueCommand): Promise<void> {
+    const issue = await this.issueRepository.findById(command.id, command.userId);
+
+    if (!issue) {
+      throw new IssueNotFoundException(command.id);
+    }
+
+    if (!issue.observers.includes(command.userId)) return;
+
+    issue.removeObserver(command.userId);
+    await this.issueRepository.update(issue, command.userId);
+
+    this.issueEventsService.emitIssueUpdated(IssueApplicationMapper.toDto(issue));
+  }
+}

src/modules/issue/application/use-cases/update-issue/update-issue.command.ts

@@ -8,5 +8,10 @@ export class UpdateIssueCommand {
     public readonly priority?: number,
     public readonly assignee?: string | null,
     public readonly dueDate?: Date | null,
+    public readonly type?: string,
+    /** Полный новый список наблюдателей */
+    public readonly observers?: string[],
+    /** Имена тегов (полный новый список); отсутствующие в справочнике проекта создаются */
+    public readonly tags?: string[],
   ) {}
 }

src/modules/issue/application/use-cases/update-issue/update-issue.use-case.spec.ts

@@ -1,15 +1,27 @@
 import { beforeEach, describe, expect, it, vi } from 'vitest';
 import type { IIssueRepository } from '../../../domain/repositories/issue.repository.interface.js';
+import type { ITagRepository } from '../../../../tag/domain/repositories/tag.repository.interface.js';
+import { buildTag, mockTagRepository } from '../../../../tag/application/use-cases/test-helpers.js';
 import type { IProjectRepository } from '../../../../project/domain/repositories/project.repository.interface.js';
 import { Issue } from '../../../domain/entities/issue.entity.js';
 import { IssueNotFoundException } from '../../../domain/exceptions/issue-not-found.exception.js';
+import { IssueEditForbiddenException } from '../../../domain/exceptions/issue-edit-forbidden.exception.js';
+import { IssueObserverNotFoundException } from '../../../domain/exceptions/issue-observer-not-found.exception.js';
 import { UpdateIssueUseCase } from './update-issue.use-case.js';
 import { UpdateIssueCommand } from './update-issue.command.js';
 import { IssueEventsService } from '../../services/issue-events.service.js';
 import { IssueUserExpanderService } from '../../services/issue-user-expander.service.js';
 import { IssueApplicationMapper } from '../../mappers/issue-application.mapper.js';
+import { IssueAssignmentNotifierService } from '../../services/issue-assignment-notifier.service.js';
+import type { NotificationsService } from '../../../../notification/application/services/notifications.service.js';
+import { IssueParticipantsService } from '../../services/issue-participants.service.js';
+import type { GetUsersUseCase } from '../../../../user/application/use-cases/get-users/get-users.use-case.js';
+import type { GetUsersQuery } from '../../../../user/application/use-cases/get-users/get-users.query.js';
 
-const buildIssue = () =>
+const backend = { id: 'tag-1', name: 'backend', color: 'primary' };
+const ui = { id: 'tag-2', name: 'ui', color: 'default' };
+
+const buildIssue = (overrides: { assignee?: string | null; observers?: string[]; tags?: Array<typeof backend> } = {}) =>
   Issue.reconstitute({
     id: 1,
     key: 'ISSUE-1',
@@ -17,12 +29,14 @@ const buildIssue = () =>
     content: 'Original content',
     status: 'OPEN',
     priority: 0,
+    type: 'TASK',
     assignee: null,
     reporter: 'user-1',
     projectId: 'project-1',
     dueDate: null,
     createdAt: new Date('2026-01-01T00:00:00.000Z'),
     updatedAt: new Date('2026-01-01T00:00:00.000Z'),
+    ...overrides,
   });
 
 describe('UpdateIssueUseCase', () => {
@@ -30,6 +44,9 @@ describe('UpdateIssueUseCase', () => {
   let projectRepository: IProjectRepository;
   let issueEventsService: IssueEventsService;
   let issueUserExpander: IssueUserExpanderService;
+  let notificationsService: NotificationsService;
+  let getUsersUseCase: GetUsersUseCase;
+  let tagRepository: ITagRepository;
   let useCase: UpdateIssueUseCase;
 
   beforeEach(() => {
@@ -37,6 +54,7 @@ describe('UpdateIssueUseCase', () => {
       findById: vi.fn(),
       findByCKey: vi.fn(),
       findAll: vi.fn(),
+      findByDueDateRange: vi.fn(),
       countByStatus: vi.fn(),
       create: vi.fn(),
       update: vi.fn(),
@@ -48,6 +66,7 @@ describe('UpdateIssueUseCase', () => {
       create: vi.fn(),
       update: vi.fn(),
       delete: vi.fn(),
+      findRole: vi.fn(),
       addMember: vi.fn(),
     };
     issueEventsService = new IssueEventsService();
@@ -58,7 +77,22 @@ describe('UpdateIssueUseCase', () => {
         reporter: null,
       })),
     } as unknown as IssueUserExpanderService;
-    useCase = new UpdateIssueUseCase(repository, projectRepository, issueEventsService, issueUserExpander);
+    notificationsService = { notify: vi.fn() } as unknown as NotificationsService;
+    getUsersUseCase = {
+      execute: vi.fn(async (query: GetUsersQuery) => query.ids.filter((id) => id !== 'ghost').map((id) => ({ id }))),
+    } as unknown as GetUsersUseCase;
+    tagRepository = mockTagRepository([
+      buildTag({ id: backend.id, name: backend.name, color: backend.color }),
+      buildTag({ id: ui.id, name: ui.name, color: ui.color }),
+    ]);
+    useCase = new UpdateIssueUseCase(
+      repository,
+      tagRepository,
+      issueEventsService,
+      issueUserExpander,
+      new IssueAssignmentNotifierService(notificationsService),
+      new IssueParticipantsService(projectRepository, getUsersUseCase),
+    );
   });
 
   it('applies only the fields provided in the command', async () => {
@@ -72,6 +106,14 @@ describe('UpdateIssueUseCase', () => {
     expect(repository.update).toHaveBeenCalledTimes(1);
   });
 
+  it('passes the acting user to the repository as the author of the changes', async () => {
+    vi.mocked(repository.findById).mockResolvedValue(buildIssue({ assignee: 'user-7' }));
+
+    await useCase.execute(new UpdateIssueCommand(1, 'user-7', undefined, undefined, 'DONE'));
+
+    expect(repository.update).toHaveBeenCalledWith(expect.any(Issue), 'user-7');
+  });
+
   it('assigns and unassigns depending on the assignee value', async () => {
     vi.mocked(repository.findById).mockResolvedValue(buildIssue());
 
@@ -106,4 +148,157 @@ describe('UpdateIssueUseCase', () => {
 
     expect(received).toEqual([dto]);
   });
+
+  it('notifies the new assignee', async () => {
+    vi.mocked(repository.findById).mockResolvedValue(buildIssue());
+
+    await useCase.execute(new UpdateIssueCommand(1, 'user-1', undefined, undefined, undefined, undefined, 'user-9'));
+
+    expect(notificationsService.notify).toHaveBeenCalledWith({
+      userId: 'user-9',
+      subject: 'You have been assigned to ISSUE-1',
+      content: 'Original title',
+    });
+  });
+
+  it('notifies the user who assigns the issue to themselves', async () => {
+    vi.mocked(repository.findById).mockResolvedValue(buildIssue());
+
+    await useCase.execute(new UpdateIssueCommand(1, 'user-1', undefined, undefined, undefined, undefined, 'user-1'));
+
+    expect(notificationsService.notify).toHaveBeenCalledWith(expect.objectContaining({ userId: 'user-1' }));
+  });
+
+  it('does not notify on unassignment or other field changes', async () => {
+    vi.mocked(repository.findById).mockResolvedValue(buildIssue());
+    await useCase.execute(new UpdateIssueCommand(1, 'user-1', undefined, undefined, undefined, undefined, null));
+
+    vi.mocked(repository.findById).mockResolvedValue(buildIssue());
+    await useCase.execute(new UpdateIssueCommand(1, 'user-1', 'New title'));
+
+    expect(notificationsService.notify).not.toHaveBeenCalled();
+  });
+
+  it('changes the issue type', async () => {
+    vi.mocked(repository.findById).mockResolvedValue(buildIssue());
+
+    const dto = await useCase.execute(
+      new UpdateIssueCommand(1, 'user-1', undefined, undefined, undefined, undefined, undefined, undefined, 'BUG'),
+    );
+
+    expect(dto.type).toBe('BUG');
+  });
+
+  it('replaces the tags by name and saves the change to history', async () => {
+    vi.mocked(repository.findById).mockResolvedValue(buildIssue({ tags: [backend, ui] }));
+    let changes: unknown[] = [];
+    vi.mocked(repository.update).mockImplementation(async (issue) => {
+      changes = issue.pullChanges();
+    });
+
+    const dto = await useCase.execute(
+      new UpdateIssueCommand(
+        1,
+        'user-1',
+        undefined,
+        undefined,
+        undefined,
+        undefined,
+        undefined,
+        undefined,
+        undefined,
+        undefined,
+        ['UI', 'api'],
+      ),
+    );
+
+    expect(tagRepository.findOrCreateByNames).toHaveBeenCalledWith('project-1', ['UI', 'api']);
+    expect(dto.tags.map((tag) => tag.name)).toEqual(['api', 'ui']);
+    expect(changes).toEqual([
+      { field: 'tag', oldValue: 'backend', newValue: null },
+      { field: 'tag', oldValue: null, newValue: 'api' },
+    ]);
+  });
+
+  it('keeps the tags when they are not passed', async () => {
+    vi.mocked(repository.findById).mockResolvedValue(buildIssue({ tags: [backend] }));
+
+    const dto = await useCase.execute(new UpdateIssueCommand(1, 'user-1', 'New title'));
+
+    expect(dto.tags).toEqual([backend]);
+    expect(tagRepository.findOrCreateByNames).not.toHaveBeenCalled();
+  });
+
+  describe('observers', () => {
+    it('forbids an observer from editing the issue', async () => {
+      vi.mocked(repository.findById).mockResolvedValue(buildIssue({ observers: ['user-5'] }));
+
+      await expect(useCase.execute(new UpdateIssueCommand(1, 'user-5', 'Hijacked'))).rejects.toBeInstanceOf(
+        IssueEditForbiddenException,
+      );
+      expect(repository.update).not.toHaveBeenCalled();
+    });
+
+    it('replaces observers, adds them to the project and notifies only the new ones', async () => {
+      vi.mocked(repository.findById).mockResolvedValue(buildIssue({ observers: ['user-5', 'user-6'] }));
+
+      const dto = await useCase.execute(
+        new UpdateIssueCommand(
+          1,
+          'user-1',
+          undefined,
+          undefined,
+          undefined,
+          undefined,
+          undefined,
+          undefined,
+          undefined,
+          ['user-6', 'user-8'],
+        ),
+      );
+
+      expect(dto.observerIds).toEqual(['user-6', 'user-8']);
+      expect(getUsersUseCase.execute).toHaveBeenCalledWith(expect.objectContaining({ ids: ['user-8'] }));
+      expect(projectRepository.addMember).toHaveBeenCalledWith('project-1', 'user-8', 'OBSERVER');
+      expect(notificationsService.notify).toHaveBeenCalledTimes(1);
+      expect(notificationsService.notify).toHaveBeenCalledWith({
+        userId: 'user-8',
+        subject: 'You are now observing ISSUE-1',
+        content: 'Original title',
+      });
+    });
+
+    it('rejects unknown users before saving', async () => {
+      vi.mocked(repository.findById).mockResolvedValue(buildIssue());
+
+      await expect(
+        useCase.execute(
+          new UpdateIssueCommand(
+            1,
+            'user-1',
+            undefined,
+            undefined,
+            undefined,
+            undefined,
+            undefined,
+            undefined,
+            undefined,
+            ['ghost'],
+          ),
+        ),
+      ).rejects.toBeInstanceOf(IssueObserverNotFoundException);
+      expect(repository.update).not.toHaveBeenCalled();
+    });
+
+    it('drops the new assignee from observers', async () => {
+      vi.mocked(repository.findById).mockResolvedValue(buildIssue({ observers: ['user-5'] }));
+
+      const dto = await useCase.execute(
+        new UpdateIssueCommand(1, 'user-1', undefined, undefined, undefined, undefined, 'user-5'),
+      );
+
+      expect(dto.assigneeId).toBe('user-5');
+      expect(dto.observerIds).toEqual([]);
+    });
+  });
 });

src/modules/issue/application/use-cases/update-issue/update-issue.use-case.ts

@@ -1,25 +1,28 @@
 import { Inject, Injectable } from '@nestjs/common';
 import { ISSUE_REPOSITORY, type IIssueRepository } from '../../../domain/repositories/issue.repository.interface.js';
-import {
-  PROJECT_REPOSITORY,
-  type IProjectRepository,
-} from '../../../../project/domain/repositories/project.repository.interface.js';
 import { IssueNotFoundException } from '../../../domain/exceptions/issue-not-found.exception.js';
+import { IssueEditForbiddenException } from '../../../domain/exceptions/issue-edit-forbidden.exception.js';
 import { UpdateIssueCommand } from './update-issue.command.js';
+import { IssueApplicationMapper } from '../../mappers/issue-application.mapper.js';
 import { IssueWithUsersDto } from '../../dto/issue-with-users.dto.js';
 import { IssueEventsService } from '../../services/issue-events.service.js';
 import { IssueUserExpanderService } from '../../services/issue-user-expander.service.js';
+import { IssueAssignmentNotifierService } from '../../services/issue-assignment-notifier.service.js';
+import { IssueParticipantsService } from '../../services/issue-participants.service.js';
 import { IssueUpdatedEvent } from '../../../domain/events/issue-updated.event.js';
+import { TAG_REPOSITORY, type ITagRepository } from '../../../../tag/domain/repositories/tag.repository.interface.js';
 
 @Injectable()
 export class UpdateIssueUseCase {
   constructor(
     @Inject(ISSUE_REPOSITORY)
     private readonly issueRepository: IIssueRepository,
-    @Inject(PROJECT_REPOSITORY)
+    @Inject(TAG_REPOSITORY)
-    private readonly projectRepository: IProjectRepository,
+    private readonly tagRepository: ITagRepository,
     private readonly issueEventsService: IssueEventsService,
     private readonly issueUserExpander: IssueUserExpanderService,
+    private readonly issueAssignmentNotifier: IssueAssignmentNotifierService,
+    private readonly issueParticipants: IssueParticipantsService,
   ) {}
 
   async execute(command: UpdateIssueCommand): Promise<IssueWithUsersDto> {
@@ -29,6 +32,12 @@ export class UpdateIssueUseCase {
       throw new IssueNotFoundException(command.id);
     }
 
+    if (!issue.canBeEditedBy(command.userId)) {
+      throw new IssueEditForbiddenException(command.id);
+    }
+
+    const observersBefore = [...issue.observers];
+
     if (command.title !== undefined) {
       issue.updateTitle(command.title);
     }
@@ -45,6 +54,10 @@ export class UpdateIssueUseCase {
       issue.changePriority(command.priority);
     }
 
+    if (command.type !== undefined) {
+      issue.changeType(command.type);
+    }
+
     if (command.assignee !== undefined) {
       if (command.assignee === null || command.assignee === '') {
         issue.unassign();
@@ -57,14 +70,27 @@ export class UpdateIssueUseCase {
       issue.updateDueDate(command.dueDate);
     }
 
-    await this.issueRepository.update(issue);
+    // После assignee: новый исполнитель отбрасывается из наблюдателей
-    const dto = await this.issueUserExpander.expand(issue);
+    if (command.observers !== undefined) {
-
+      issue.setObservers(command.observers);
-    if (issue.assignee) {
-      await this.projectRepository.addMember(issue.projectId, issue.assignee);
     }
 
+    if (command.tags !== undefined) {
+      issue.setTags(
+        (await this.tagRepository.findOrCreateByNames(issue.projectId, command.tags)).map(
+          IssueApplicationMapper.toTagRef,
+        ),
+      );
+    }
+
+    await this.issueParticipants.ensureObserversExist(issue.observers.filter((id) => !observersBefore.includes(id)));
+    await this.issueRepository.update(issue, command.userId);
+    const dto = await this.issueUserExpander.expand(issue);
+
+    await this.issueParticipants.addToProject(issue);
+
     const domainEvents = issue.pullDomainEvents();
+    this.issueAssignmentNotifier.notify(issue, domainEvents);
     if (domainEvents.some((event) => event instanceof IssueUpdatedEvent)) {
       this.issueEventsService.emitIssueUpdated(dto);
     }

src/modules/issue/domain/entities/issue-change.ts

@@ -0,0 +1,30 @@
+/**
+ * Поля задачи, изменения которых пишутся в историю (таблица issue_change).
+ * created — служебное «поле»: строка о создании задачи, значения пустые.
+ */
+export const ISSUE_CHANGE_FIELDS = [
+  'created',
+  'title',
+  'content',
+  'status',
+  'priority',
+  'type',
+  'assignee',
+  'dueDate',
+  'observer',
+  'tag',
+] as const;
+
+export type IssueChangeField = (typeof ISSUE_CHANGE_FIELDS)[number];
+
+/**
+ * Изменение одного поля задачи. Значения сериализованы в строки:
+ * priority — число, dueDate — ISO-дата, assignee — id пользователя.
+ * observer — одна строка на наблюдателя: добавлен (oldValue = null, newValue = id)
+ * или снят (oldValue = id, newValue = null). tag — так же, по строке на тег.
+ */
+export interface IssueFieldChange {
+  field: IssueChangeField;
+  oldValue: string | null;
+  newValue: string | null;
+}

src/modules/issue/domain/entities/issue.entity.spec.ts

@@ -1,6 +1,8 @@
 import { describe, expect, it } from 'vitest';
 import { Issue } from './issue.entity.js';
 import { IssueCreatedEvent } from '../events/issue-created.event.js';
+import { IssueAssignedEvent } from '../events/issue-assigned.event.js';
+import { IssueObserverAddedEvent } from '../events/issue-observer-added.event.js';
 
 describe('Issue', () => {
   describe('create', () => {
@@ -18,6 +20,7 @@ describe('Issue', () => {
       expect(issue.content).toBeNull();
       expect(issue.status).toBe('OPEN');
       expect(issue.priority).toBe(0);
+      expect(issue.type).toBe('TASK');
       expect(issue.assignee).toBeNull();
       expect(issue.reporter).toBe('user-1');
     });
@@ -30,11 +33,13 @@ describe('Issue', () => {
         projectId: 'project-1',
         content: 'Details here',
         priority: 3,
+        type: 'BUG',
         assignee: 'user-2',
       });
 
       expect(issue.content).toBe('Details here');
       expect(issue.priority).toBe(3);
+      expect(issue.type).toBe('BUG');
       expect(issue.assignee).toBe('user-2');
     });
 
@@ -69,6 +74,7 @@ describe('Issue', () => {
         content: null,
         status: 'IN_PROGRESS',
         priority: 2,
+        type: 'TASK',
         assignee: 'user-3',
         reporter: 'user-1',
         projectId: 'project-1',
@@ -92,6 +98,7 @@ describe('Issue', () => {
         content: null,
         status: 'OPEN',
         priority: 0,
+        type: 'TASK',
         assignee: null,
         reporter: 'user-1',
         projectId: 'project-1',
@@ -138,6 +145,15 @@ describe('Issue', () => {
       expect(() => issue.changePriority(10)).toThrow();
     });
 
+    it('changes the type through the value object rules', () => {
+      const issue = build();
+
+      issue.changeType('FEATURE');
+      expect(issue.type).toBe('FEATURE');
+
+      expect(() => issue.changeType('EPIC')).toThrow();
+    });
+
     it('assigns and unassigns an issue', () => {
       const issue = build();
 
@@ -147,5 +163,261 @@ describe('Issue', () => {
       issue.unassign();
       expect(issue.assignee).toBeNull();
     });
+
+    it('raises IssueAssignedEvent only when the assignee actually changes', () => {
+      const issue = build();
+
+      issue.assignTo('user-9');
+      issue.assignTo('user-9');
+
+      const assigned = issue.pullDomainEvents().filter((event) => event instanceof IssueAssignedEvent);
+      expect(assigned).toEqual([expect.objectContaining({ issueKey: issue.key, assignee: 'user-9' })]);
+    });
+  });
+
+  describe('change tracking', () => {
+    const build = () =>
+      Issue.reconstitute({
+        id: 1,
+        key: 'ISSUE-1',
+        title: 'Title',
+        content: null,
+        status: 'OPEN',
+        priority: 0,
+        type: 'TASK',
+        assignee: null,
+        reporter: 'user-1',
+        projectId: 'project-1',
+        dueDate: null,
+        createdAt: new Date('2026-01-01T00:00:00.000Z'),
+        updatedAt: new Date('2026-01-01T00:00:00.000Z'),
+      });
+
+    it('records creation and the initial OPEN status for a new issue', () => {
+      const issue = Issue.create({ key: 'ISSUE-1', title: 'Title', reporter: 'user-1', projectId: 'project-1' });
+
+      expect(issue.pullChanges()).toEqual([
+        { field: 'created', oldValue: null, newValue: null },
+        { field: 'status', oldValue: null, newValue: 'OPEN' },
+      ]);
+    });
+
+    it('records every changed field with serialized values', () => {
+      const issue = build();
+
+      issue.updateTitle('New title');
+      issue.updateContent('Text');
+      issue.changeStatus('IN_PROGRESS');
+      issue.changePriority(3);
+      issue.changeType('BUG');
+      issue.assignTo('user-2');
+      issue.updateDueDate(new Date('2026-02-01T00:00:00.000Z'));
+
+      expect(issue.pullChanges()).toEqual([
+        { field: 'title', oldValue: 'Title', newValue: 'New title' },
+        { field: 'content', oldValue: null, newValue: 'Text' },
+        { field: 'status', oldValue: 'OPEN', newValue: 'IN_PROGRESS' },
+        { field: 'priority', oldValue: '0', newValue: '3' },
+        { field: 'type', oldValue: 'TASK', newValue: 'BUG' },
+        { field: 'assignee', oldValue: null, newValue: 'user-2' },
+        { field: 'dueDate', oldValue: null, newValue: '2026-02-01T00:00:00.000Z' },
+      ]);
+      expect(issue.pullChanges()).toEqual([]);
+    });
+
+    it('ignores setting the same value: no change, no event, no updatedAt bump', () => {
+      const issue = build();
+      const before = issue.updatedAt;
+
+      issue.updateTitle('Title');
+      issue.changeStatus('OPEN');
+      issue.unassign();
+
+      expect(issue.pullChanges()).toEqual([]);
+      expect(issue.pullDomainEvents()).toEqual([]);
+      expect(issue.updatedAt).toBe(before);
+    });
+
+    it('merges repeated changes of a field and drops a change reverted to the original', () => {
+      const issue = build();
+
+      issue.changeStatus('IN_PROGRESS');
+      issue.changeStatus('DONE');
+      issue.assignTo('user-2');
+      issue.unassign();
+
+      expect(issue.pullChanges()).toEqual([{ field: 'status', oldValue: 'OPEN', newValue: 'DONE' }]);
+    });
+  });
+
+  describe('observers', () => {
+    const load = (observers: string[] = []) =>
+      Issue.reconstitute({
+        id: 1,
+        key: 'ISSUE-1',
+        title: 'Title',
+        content: null,
+        status: 'OPEN',
+        priority: 0,
+        type: 'TASK',
+        assignee: 'user-2',
+        reporter: 'user-1',
+        observers,
+        projectId: 'project-1',
+        dueDate: null,
+        createdAt: new Date(),
+        updatedAt: new Date(),
+      });
+
+    it('only the reporter and the assignee can edit the issue', () => {
+      const issue = load(['user-3']);
+
+      expect(issue.canBeEditedBy('user-1')).toBe(true);
+      expect(issue.canBeEditedBy('user-2')).toBe(true);
+      expect(issue.canBeEditedBy('user-3')).toBe(false);
+    });
+
+    it('creates an issue with observers, skipping duplicates, the reporter and the assignee', () => {
+      const issue = Issue.create({
+        key: 'ISSUE-1',
+        title: 'Title',
+        reporter: 'user-1',
+        assignee: 'user-2',
+        observers: ['user-3', 'user-1', 'user-2', 'user-3', 'user-4'],
+        projectId: 'project-1',
+      });
+
+      expect(issue.observers).toEqual(['user-3', 'user-4']);
+      expect(issue.pullDomainEvents().filter((event) => event instanceof IssueObserverAddedEvent)).toEqual([
+        expect.objectContaining({ observer: 'user-3' }),
+        expect.objectContaining({ observer: 'user-4' }),
+      ]);
+      expect(issue.pullChanges().map((change) => change.field)).toEqual(['created', 'status']);
+    });
+
+    it('records one history row per added or removed observer', () => {
+      const issue = load(['user-3', 'user-4']);
+
+      issue.setObservers(['user-4', 'user-5']);
+
+      expect(issue.observers).toEqual(['user-4', 'user-5']);
+      expect(issue.pullChanges()).toEqual([
+        { field: 'observer', oldValue: 'user-3', newValue: null },
+        { field: 'observer', oldValue: null, newValue: 'user-5' },
+      ]);
+    });
+
+    it('does nothing when the list is unchanged', () => {
+      const issue = load(['user-3']);
+
+      issue.setObservers(['user-3', 'user-1']);
+
+      expect(issue.pullChanges()).toEqual([]);
+      expect(issue.pullDomainEvents()).toEqual([]);
+    });
+
+    it('cancels out adding and removing the same observer', () => {
+      const issue = load();
+
+      issue.addObserver('user-3');
+      issue.removeObserver('user-3');
+
+      expect(issue.pullChanges()).toEqual([]);
+    });
+
+    it('removes the observer who becomes the assignee', () => {
+      const issue = load(['user-3']);
+
+      issue.assignTo('user-3');
+
+      expect(issue.observers).toEqual([]);
+      expect(issue.pullChanges()).toEqual([
+        { field: 'assignee', oldValue: 'user-2', newValue: 'user-3' },
+        { field: 'observer', oldValue: 'user-3', newValue: null },
+      ]);
+    });
+  });
+
+  describe('tags', () => {
+    const backend = { id: 't1', name: 'backend', color: 'primary' };
+    const ui = { id: 't2', name: 'UI', color: 'default' };
+    const api = { id: 't3', name: 'api', color: 'success' };
+
+    const load = (tags: Array<typeof backend> = []) =>
+      Issue.reconstitute({
+        id: 1,
+        key: 'ISSUE-1',
+        title: 'Title',
+        content: null,
+        status: 'OPEN',
+        priority: 0,
+        type: 'TASK',
+        assignee: 'user-2',
+        reporter: 'user-1',
+        tags,
+        projectId: 'project-1',
+        dueDate: null,
+        createdAt: new Date(),
+        updatedAt: new Date(),
+      });
+
+    it('creates an issue with tags sorted by name without writing them to history', () => {
+      const issue = Issue.create({
+        key: 'ISSUE-1',
+        title: 'Title',
+        reporter: 'user-1',
+        tags: [ui, backend, ui],
+        projectId: 'project-1',
+      });
+
+      expect(issue.tags).toEqual([backend, ui]);
+      expect(issue.pullChanges().map((change) => change.field)).toEqual(['created', 'status']);
+    });
+
+    it('has no tags by default', () => {
+      expect(load().tags).toEqual([]);
+    });
+
+    it('records one history row per added or removed tag, with the tag name', () => {
+      const issue = load([backend, ui]);
+
+      issue.setTags([ui, api]);
+
+      expect(issue.tags).toEqual([api, ui]);
+      expect(issue.pullChanges()).toEqual([
+        { field: 'tag', oldValue: 'backend', newValue: null },
+        { field: 'tag', oldValue: null, newValue: 'api' },
+      ]);
+      expect(issue.pullDomainEvents()).not.toHaveLength(0);
+    });
+
+    it('does not record a change when the same tags are set', () => {
+      const issue = load([backend, ui]);
+      const updatedAt = issue.updatedAt;
+
+      issue.setTags([ui, backend]);
+
+      expect(issue.pullChanges()).toEqual([]);
+      expect(issue.pullDomainEvents()).toEqual([]);
+      expect(issue.updatedAt).toBe(updatedAt);
+    });
+
+    it('cancels out adding and removing the same tag', () => {
+      const issue = load([backend]);
+
+      issue.setTags([backend, ui]);
+      issue.setTags([backend]);
+
+      expect(issue.pullChanges()).toEqual([]);
+    });
+
+    it('removes all tags', () => {
+      const issue = load([backend]);
+
+      issue.setTags([]);
+
+      expect(issue.tags).toEqual([]);
+      expect(issue.pullChanges()).toEqual([{ field: 'tag', oldValue: 'backend', newValue: null }]);
+    });
   });
 });

src/modules/issue/domain/entities/issue.entity.ts

@@ -1,8 +1,13 @@
 import { IssueTitle } from '../value-objects/issue-title.vo.js';
 import { IssueStatus } from '../value-objects/issue-status.vo.js';
 import { IssuePriority } from '../value-objects/issue-priority.vo.js';
+import { IssueType } from '../value-objects/issue-type.vo.js';
+import { IssueTags, type IssueTagRef } from '../value-objects/issue-tags.vo.js';
 import { IssueCreatedEvent } from '../events/issue-created.event.js';
 import { IssueUpdatedEvent } from '../events/issue-updated.event.js';
+import { IssueAssignedEvent } from '../events/issue-assigned.event.js';
+import { IssueObserverAddedEvent } from '../events/issue-observer-added.event.js';
+import type { IssueChangeField, IssueFieldChange } from './issue-change.js';
 
 interface IssueProps {
   id: number | null;
@@ -11,9 +16,13 @@ interface IssueProps {
   content: string | null;
   status: IssueStatus;
   priority: IssuePriority;
+  type: IssueType;
   assignee: string | null;
   /** null — автор задачи удалил аккаунт */
   reporter: string | null;
+  /** Видят задачу и комментируют, но не редактируют. Не пересекаются с reporter/assignee. */
+  observers: string[];
+  tags: IssueTags;
   projectId: string;
   dueDate: Date | null;
   createdAt: Date;
@@ -27,9 +36,17 @@ interface IssueProps {
  * `id` — Int, генерируется базой данных (SERIAL), поэтому у новой задачи
  * он равен null до сохранения в репозитории. `key` (например, "ISSUE-1")
  * присваивается на уровне приложения при создании и не зависит от id.
+ *
+ * Сущность копит изменения полей (pullChanges) — репозиторий сохраняет их
+ * в историю в той же транзакции, что и саму задачу.
  */
 export class Issue {
   private domainEvents: unknown[] = [];
+  /**
+   * Несохранённые изменения полей, по одному на поле, в порядке изменения.
+   * Ключ — поле, для observer — поле и id наблюдателя, для tag — поле и id тега.
+   */
+  private changes = new Map<string, IssueFieldChange>();
 
   private constructor(private readonly props: IssueProps) {}
 
@@ -39,8 +56,11 @@ export class Issue {
     title: string;
     content?: string | null;
     priority?: number;
+    type?: string;
     assignee?: string | null;
     reporter: string;
+    observers?: string[];
+    tags?: IssueTagRef[];
     projectId: string;
     dueDate?: Date | null;
   }): Issue {
@@ -51,15 +71,29 @@ export class Issue {
       content: params.content ?? null,
       status: IssueStatus.open(),
       priority: params.priority !== undefined ? IssuePriority.create(params.priority) : IssuePriority.default(),
+      type: params.type !== undefined ? IssueType.create(params.type) : IssueType.default(),
       assignee: params.assignee ?? null,
       reporter: params.reporter,
+      observers: [],
+      // Как и наблюдатели, теги при создании в историю не пишутся
+      tags: IssueTags.create(params.tags ?? []),
       projectId: params.projectId,
       dueDate: params.dueDate ?? null,
       createdAt: new Date(),
       updatedAt: new Date(),
     });
 
+    issue.changes.set('created', { field: 'created', oldValue: null, newValue: null });
+    issue.changes.set('status', { field: 'status', oldValue: null, newValue: issue.status });
     issue.addDomainEvent(new IssueCreatedEvent(issue.key));
+    if (issue.assignee) {
+      issue.addDomainEvent(new IssueAssignedEvent(issue.key, issue.assignee));
+    }
+    // Как и assignee, наблюдатели при создании в историю не пишутся — только события
+    for (const userId of issue.normalizeObservers(params.observers ?? [])) {
+      issue.props.observers.push(userId);
+      issue.addDomainEvent(new IssueObserverAddedEvent(issue.key, userId));
+    }
 
     return issue;
   }
@@ -72,8 +106,11 @@ export class Issue {
     content: string | null;
     status: string;
     priority: number;
+    type: string;
     assignee: string | null;
     reporter: string | null;
+    observers?: string[];
+    tags?: IssueTagRef[];
     projectId: string;
     dueDate: Date | null;
     createdAt: Date;
@@ -86,8 +123,11 @@ export class Issue {
       content: props.content,
       status: IssueStatus.create(props.status),
       priority: IssuePriority.create(props.priority),
+      type: IssueType.create(props.type),
       assignee: props.assignee,
       reporter: props.reporter,
+      observers: [...(props.observers ?? [])],
+      tags: IssueTags.create(props.tags ?? []),
       projectId: props.projectId,
       dueDate: props.dueDate,
       createdAt: props.createdAt,
@@ -119,6 +159,10 @@ export class Issue {
     return this.props.priority.value;
   }
 
+  get type(): string {
+    return this.props.type.value;
+  }
+
   get assignee(): string | null {
     return this.props.assignee;
   }
@@ -127,6 +171,19 @@ export class Issue {
     return this.props.reporter;
   }
 
+  get observers(): readonly string[] {
+    return this.props.observers;
+  }
+
+  get tags(): readonly IssueTagRef[] {
+    return this.props.tags.value;
+  }
+
+  /** Редактировать задачу могут только reporter и assignee, наблюдатели — нет */
+  canBeEditedBy(userId: string): boolean {
+    return this.reporter === userId || this.assignee === userId;
+  }
+
   get projectId(): string {
     return this.props.projectId;
   }
@@ -144,40 +201,135 @@ export class Issue {
   }
 
   updateTitle(title: string): void {
-    this.props.title = IssueTitle.create(title);
+    const next = IssueTitle.create(title);
-    this.touch();
+    this.recordChange('title', this.title, next.value);
+    this.props.title = next;
   }
 
   updateContent(content: string | null): void {
+    this.recordChange('content', this.content, content);
     this.props.content = content;
-    this.touch();
   }
 
   changeStatus(status: string): void {
-    this.props.status = IssueStatus.create(status);
+    const next = IssueStatus.create(status);
-    this.touch();
+    this.recordChange('status', this.status, next.value);
+    this.props.status = next;
   }
 
   changePriority(priority: number): void {
-    this.props.priority = IssuePriority.create(priority);
+    const next = IssuePriority.create(priority);
-    this.touch();
+    this.recordChange('priority', String(this.priority), String(next.value));
+    this.props.priority = next;
+  }
+
+  changeType(type: string): void {
+    const next = IssueType.create(type);
+    this.recordChange('type', this.type, next.value);
+    this.props.type = next;
   }
 
   assignTo(userId: string): void {
+    if (this.assignee === userId) return;
+
+    this.recordChange('assignee', this.assignee, userId);
     this.props.assignee = userId;
-    this.touch();
+    this.addDomainEvent(new IssueAssignedEvent(this.key, userId));
+    // Исполнитель и так видит задачу и может её редактировать
+    this.removeObserver(userId);
   }
 
   unassign(): void {
+    this.recordChange('assignee', this.assignee, null);
     this.props.assignee = null;
-    this.touch();
   }
 
   updateDueDate(dueDate: Date | null): void {
+    this.recordChange('dueDate', this.dueDate?.toISOString() ?? null, dueDate?.toISOString() ?? null);
     this.props.dueDate = dueDate;
+  }
+
+  /**
+   * Заменяет список наблюдателей. reporter и assignee отбрасываются:
+   * у них и так больше прав, чем у наблюдателя.
+   */
+  setObservers(userIds: string[]): void {
+    const next = this.normalizeObservers(userIds);
+    for (const userId of this.observers.filter((id) => !next.includes(id))) {
+      this.removeObserver(userId);
+    }
+    for (const userId of next) {
+      this.addObserver(userId);
+    }
+  }
+
+  addObserver(userId: string): void {
+    if (this.observers.includes(userId) || this.normalizeObservers([userId]).length === 0) return;
+
+    this.recordChange('observer', null, userId, `observer:${userId}`);
+    this.props.observers.push(userId);
+    this.addDomainEvent(new IssueObserverAddedEvent(this.key, userId));
+  }
+
+  removeObserver(userId: string): void {
+    if (!this.observers.includes(userId)) return;
+
+    this.recordChange('observer', userId, null, `observer:${userId}`);
+    this.props.observers = this.props.observers.filter((id) => id !== userId);
+  }
+
+  /**
+   * Заменяет теги задачи — теги справочника её проекта (их находит/создаёт use-case).
+   * В историю — по строке на добавленный или снятый тег, со значением-именем тега.
+   */
+  setTags(tags: IssueTagRef[]): void {
+    const next = IssueTags.create(tags);
+    for (const tag of this.tags.filter((tag) => !next.has(tag.id))) {
+      this.recordChange('tag', tag.name, null, `tag:${tag.id}`);
+    }
+    for (const tag of next.value.filter((tag) => !this.props.tags.has(tag.id))) {
+      this.recordChange('tag', null, tag.name, `tag:${tag.id}`);
+    }
+    this.props.tags = next;
+  }
+
+  /** Изменения полей, накопленные с момента загрузки/создания. Забираются один раз. */
+  pullChanges(): IssueFieldChange[] {
+    const changes = [...this.changes.values()];
+    this.changes.clear();
+    return changes;
+  }
+
+  /**
+   * Запоминает изменение поля. Присвоение того же значения — не изменение:
+   * ни updatedAt, ни событие, ни запись в историю. Повторная правка поля
+   * сливается с предыдущей, а возврат к исходному значению её отменяет.
+   */
+  private recordChange(
+    field: IssueChangeField,
+    oldValue: string | null,
+    newValue: string | null,
+    key: string = field,
+  ): void {
+    if (oldValue === newValue) return;
+
+    const pending = this.changes.get(key);
+    if (!pending) {
+      this.changes.set(key, { field, oldValue, newValue });
+    } else if (pending.oldValue === newValue) {
+      this.changes.delete(key);
+    } else {
+      pending.newValue = newValue;
+    }
+
     this.touch();
   }
 
+  /** Уникальные id без reporter/assignee, в исходном порядке */
+  private normalizeObservers(userIds: string[]): string[] {
+    return [...new Set(userIds)].filter((id) => id !== '' && id !== this.reporter && id !== this.assignee);
+  }
+
   private touch(): void {
     this.props.updatedAt = new Date();
     this.addDomainEvent(new IssueUpdatedEvent(this.key));

src/modules/issue/domain/events/issue-assigned.event.ts

@@ -0,0 +1,7 @@
+export class IssueAssignedEvent {
+  constructor(
+    public readonly issueKey: string,
+    public readonly assignee: string,
+    public readonly occurredAt: Date = new Date(),
+  ) {}
+}

src/modules/issue/domain/events/issue-observer-added.event.ts

@@ -0,0 +1,7 @@
+export class IssueObserverAddedEvent {
+  constructor(
+    public readonly issueKey: string,
+    public readonly observer: string,
+    public readonly occurredAt: Date = new Date(),
+  ) {}
+}

src/modules/issue/domain/exceptions/invalid-calendar-range.exception.ts

@@ -0,0 +1,6 @@
+export class InvalidCalendarRangeException extends Error {
+  constructor(message: string) {
+    super(message);
+    this.name = 'InvalidCalendarRangeException';
+  }
+}

src/modules/issue/domain/exceptions/issue-edit-forbidden.exception.ts

@@ -0,0 +1,7 @@
+/** Задача видна пользователю (он наблюдатель), но редактировать её он не может */
+export class IssueEditForbiddenException extends Error {
+  constructor(id: number) {
+    super(`Задача с id=${id} доступна наблюдателю только для чтения`);
+    this.name = 'IssueEditForbiddenException';
+  }
+}

src/modules/issue/domain/exceptions/issue-observer-not-found.exception.ts

@@ -0,0 +1,6 @@
+export class IssueObserverNotFoundException extends Error {
+  constructor(userIds: string[]) {
+    super(`Пользователи не найдены: ${userIds.join(', ')}`);
+    this.name = 'IssueObserverNotFoundException';
+  }
+}

src/modules/issue/domain/exceptions/issue-project-forbidden.exception.ts

@@ -0,0 +1,7 @@
+/** Проект виден пользователю (он наблюдатель), но создавать в нём задачи он не может */
+export class IssueProjectForbiddenException extends Error {
+  constructor(projectId: string) {
+    super(`В проекте с id=${projectId} наблюдатель не может создавать задачи`);
+    this.name = 'IssueProjectForbiddenException';
+  }
+}

src/modules/issue/domain/repositories/issue.repository.interface.ts

@@ -4,21 +4,43 @@ import { PaginationMeta } from '../../../../common/interfaces/pagination-meta.in
 /** DI-токен, т.к. интерфейсы стираются при компиляции TS */
 export const ISSUE_REPOSITORY = Symbol('ISSUE_REPOSITORY');
 
+/** Роль пользователя в задаче — фильтр списка «мои задачи» */
+export const ISSUE_USER_ROLES = ['assigned', 'reported', 'observing'] as const;
+export type IssueUserRole = (typeof ISSUE_USER_ROLES)[number];
+
 export interface IIssueRepository {
-  /** Задача видна только пользователю, который является в ней reporter или assignee */
+  /**
+   * Задача видна своим reporter, assignee и наблюдателям. Редактировать её
+   * могут только reporter и assignee — см. Issue.canBeEditedBy.
+   */
   findById(id: number, userId: string): Promise<Issue | null>;
   findByCKey(ckey: string, userId: string): Promise<Issue | null>;
   findAll(params: {
     limit: number;
     page: number;
     userId: string;
-    status?: string;
+    status?: string[];
     text?: string;
     assigneeId?: string;
     projectId?: string;
+    hasDueDate?: boolean;
+    type?: string[];
+    role?: IssueUserRole;
   }): Promise<{ list: Issue[]; meta: PaginationMeta }>;
+  /** Задачи с dueDate в [from, to), по возрастанию dueDate, не больше limit */
+  findByDueDateRange(params: {
+    from: Date;
+    to: Date;
+    limit: number;
+    userId: string;
+    status?: string[];
+    assigneeId?: string;
+    projectId?: string;
+  }): Promise<Issue[]>;
   countByStatus(userId: string, projectId?: string): Promise<Array<{ status: string; count: number }>>;
+  /** Сохраняет задачу и записи о её создании в историю (автор — reporter) */
   create(issue: Issue): Promise<Issue>;
-  update(issue: Issue): Promise<void>;
+  /** Сохраняет задачу, её наблюдателей и накопленные изменения полей в историю одной транзакцией */
+  update(issue: Issue, actorId: string): Promise<void>;
   delete(id: number): Promise<void>;
 }

src/modules/issue/domain/value-objects/calendar-range.vo.spec.ts

@@ -0,0 +1,37 @@
+import { describe, expect, it } from 'vitest';
+import { CalendarRange } from './calendar-range.vo.js';
+import { InvalidCalendarRangeException } from '../exceptions/invalid-calendar-range.exception.js';
+
+describe('CalendarRange', () => {
+  it('accepts a 6-week month grid', () => {
+    const from = new Date('2026-09-28T00:00:00+03:00');
+    const to = new Date('2026-11-09T00:00:00+03:00');
+
+    const range = CalendarRange.create({ from, to });
+
+    expect(range.from).toBe(from);
+    expect(range.to).toBe(to);
+  });
+
+  it('rejects an invalid date', () => {
+    expect(() => CalendarRange.create({ from: new Date('nope'), to: new Date() })).toThrow(
+      InvalidCalendarRangeException,
+    );
+  });
+
+  it('rejects from equal to or after to', () => {
+    const date = new Date('2026-10-01T00:00:00Z');
+
+    expect(() => CalendarRange.create({ from: date, to: date })).toThrow(InvalidCalendarRangeException);
+    expect(() => CalendarRange.create({ from: new Date('2026-10-02T00:00:00Z'), to: date })).toThrow(
+      InvalidCalendarRangeException,
+    );
+  });
+
+  it(`rejects a range longer than ${CalendarRange.MAX_DAYS} days`, () => {
+    const from = new Date('2026-10-01T00:00:00Z');
+    const to = new Date(from.getTime() + (CalendarRange.MAX_DAYS * 24 * 60 * 60 * 1000 + 1));
+
+    expect(() => CalendarRange.create({ from, to })).toThrow(InvalidCalendarRangeException);
+  });
+});

src/modules/issue/domain/value-objects/calendar-range.vo.ts

@@ -0,0 +1,33 @@
+import { InvalidCalendarRangeException } from '../exceptions/invalid-calendar-range.exception.js';
+
+const DAY_MS = 24 * 60 * 60 * 1000;
+
+/**
+ * Диапазон календаря по dueDate — полуоткрытый интервал [from, to).
+ * Границы — моменты времени: клиент сам считает начало/конец видимой сетки
+ * в своём часовом поясе, сервер про месяцы и часовые пояса не знает.
+ */
+export class CalendarRange {
+  /** Сетка месяца — 6 недель (42 дня), плюс запас на переход на летнее/зимнее время */
+  static readonly MAX_DAYS = 45;
+
+  private constructor(
+    public readonly from: Date,
+    public readonly to: Date,
+  ) {}
+
+  static create(params: { from: Date; to: Date }): CalendarRange {
+    const { from, to } = params;
+    if (Number.isNaN(from.getTime()) || Number.isNaN(to.getTime())) {
+      throw new InvalidCalendarRangeException('Некорректная дата from или to');
+    }
+    if (from >= to) {
+      throw new InvalidCalendarRangeException('Дата from должна быть раньше даты to');
+    }
+    if (to.getTime() - from.getTime() > CalendarRange.MAX_DAYS * DAY_MS) {
+      throw new InvalidCalendarRangeException(`Диапазон больше ${CalendarRange.MAX_DAYS} дней`);
+    }
+
+    return new CalendarRange(from, to);
+  }
+}

src/modules/issue/domain/value-objects/issue-tags.vo.spec.ts

@@ -0,0 +1,29 @@
+import { describe, expect, it } from 'vitest';
+import { IssueTags, ISSUE_TAGS_MAX_COUNT } from './issue-tags.vo.js';
+
+const tag = (id: string, name = id) => ({ id, name, color: 'default' });
+
+describe('IssueTags', () => {
+  it('sorts tags by name and drops duplicates by id', () => {
+    const tags = IssueTags.create([tag('t2', 'ui'), tag('t1', 'backend'), tag('t2', 'ui')]);
+
+    expect(tags.value.map((t) => t.name)).toEqual(['backend', 'ui']);
+  });
+
+  it('throws for too many tags', () => {
+    const tags = Array.from({ length: ISSUE_TAGS_MAX_COUNT + 1 }, (_, i) => tag(`t${i}`));
+
+    expect(() => IssueTags.create(tags)).toThrow(/не может быть больше/);
+  });
+
+  it('checks whether a tag is assigned', () => {
+    const tags = IssueTags.create([tag('t1')]);
+
+    expect(tags.has('t1')).toBe(true);
+    expect(tags.has('t2')).toBe(false);
+  });
+
+  it('is empty by default', () => {
+    expect(IssueTags.empty().value).toEqual([]);
+  });
+});

src/modules/issue/domain/value-objects/issue-tags.vo.ts

@@ -0,0 +1,35 @@
+export const ISSUE_TAGS_MAX_COUNT = 20;
+
+/** Тег из справочника проекта, назначенный задаче (снимок для отображения) */
+export interface IssueTagRef {
+  id: string;
+  name: string;
+  color: string;
+}
+
+/** Теги задачи: без повторов (по id), по алфавиту, не больше ISSUE_TAGS_MAX_COUNT */
+export class IssueTags {
+  private constructor(private readonly _value: readonly IssueTagRef[]) {}
+
+  static create(tags: IssueTagRef[]): IssueTags {
+    const unique = [...new Map(tags.map((tag) => [tag.id, { ...tag }])).values()];
+
+    if (unique.length > ISSUE_TAGS_MAX_COUNT) {
+      throw new Error(`У задачи не может быть больше ${ISSUE_TAGS_MAX_COUNT} тегов`);
+    }
+
+    return new IssueTags(unique.sort((a, b) => a.name.localeCompare(b.name)));
+  }
+
+  static empty(): IssueTags {
+    return new IssueTags([]);
+  }
+
+  get value(): readonly IssueTagRef[] {
+    return this._value;
+  }
+
+  has(tagId: string): boolean {
+    return this._value.some((tag) => tag.id === tagId);
+  }
+}

src/modules/issue/domain/value-objects/issue-type.vo.spec.ts

@@ -0,0 +1,21 @@
+import { describe, expect, it } from 'vitest';
+import { IssueType, ISSUE_TYPES } from './issue-type.vo.js';
+
+describe('IssueType', () => {
+  it.each(ISSUE_TYPES.map((type) => type.alias))('accepts the valid type "%s"', (alias) => {
+    expect(IssueType.create(alias).value).toBe(alias);
+  });
+
+  it('throws for an unknown type', () => {
+    expect(() => IssueType.create('EPIC')).toThrow(/Недопустимый тип задачи/);
+  });
+
+  it('defaults to TASK', () => {
+    expect(IssueType.default().value).toBe('TASK');
+  });
+
+  it('compares two types by value', () => {
+    expect(IssueType.create('BUG').equals(IssueType.create('BUG'))).toBe(true);
+    expect(IssueType.create('BUG').equals(IssueType.create('TASK'))).toBe(false);
+  });
+});

src/modules/issue/domain/value-objects/issue-type.vo.ts

@@ -0,0 +1,33 @@
+export const ISSUE_TYPES = [
+  { name: 'Task', alias: 'TASK', color: 'primary' },
+  { name: 'Bug', alias: 'BUG', color: 'error' },
+  { name: 'Feature', alias: 'FEATURE', color: 'success' },
+] as const;
+
+export type IssueTypeValue = (typeof ISSUE_TYPES)[number]['alias'];
+
+export const ISSUE_TYPE_ALIASES: readonly IssueTypeValue[] = ISSUE_TYPES.map((type) => type.alias);
+
+export class IssueType {
+  private constructor(private readonly _value: IssueTypeValue) {}
+
+  static create(value: string): IssueType {
+    if (!ISSUE_TYPE_ALIASES.includes(value as IssueTypeValue)) {
+      throw new Error(`Недопустимый тип задачи: "${value}". Разрешены: ${ISSUE_TYPE_ALIASES.join(', ')}`);
+    }
+
+    return new IssueType(value as IssueTypeValue);
+  }
+
+  static default(): IssueType {
+    return new IssueType('TASK');
+  }
+
+  get value(): IssueTypeValue {
+    return this._value;
+  }
+
+  equals(other: IssueType): boolean {
+    return this._value === other.value;
+  }
+}

src/modules/issue/infrastructure/persistence/prisma/mappers/issue.mapper.spec.ts

@@ -10,12 +10,15 @@ describe('IssuePrismaMapper', () => {
     content: 'Details',
     status: 'IN_PROGRESS',
     priority: 2,
+    type: 'BUG',
+    tags: [{ tag: { id: 't1', name: 'backend', color: 'primary' } }],
     assigneeId: 'user-2',
     reporterId: 'user-1',
     projectId: 'project-1',
     dueDate: null,
     createdAt: new Date('2026-01-01T00:00:00.000Z'),
     updatedAt: new Date('2026-01-02T00:00:00.000Z'),
+    observers: [{ userId: 'user-3' }],
   };
 
   it('maps a Prisma record to a domain entity', () => {
@@ -26,7 +29,10 @@ describe('IssuePrismaMapper', () => {
     expect(issue.title).toBe('Fix login bug');
     expect(issue.status).toBe('IN_PROGRESS');
     expect(issue.priority).toBe(2);
+    expect(issue.type).toBe('BUG');
     expect(issue.assignee).toBe('user-2');
+    expect(issue.observers).toEqual(['user-3']);
+    expect(issue.tags).toEqual([{ id: 't1', name: 'backend', color: 'primary' }]);
   });
 
   it('maps a new domain entity to Prisma create input', () => {
@@ -34,6 +40,7 @@ describe('IssuePrismaMapper', () => {
       key: 'ISSUE-6',
       title: 'New issue',
       reporter: 'user-1',
+      tags: [{ id: 't2', name: 'ui', color: 'default' }],
       projectId: 'project-1',
     });
 
@@ -45,8 +52,10 @@ describe('IssuePrismaMapper', () => {
       content: null,
       status: 'OPEN',
       priority: 0,
+      type: 'TASK',
       assigneeId: null,
       reporterId: 'user-1',
+      tags: { create: [{ tagId: 't2' }] },
       projectId: 'project-1',
     });
   });
@@ -61,10 +70,13 @@ describe('IssuePrismaMapper', () => {
       title: 'Updated title',
       status: 'IN_PROGRESS',
       priority: 2,
+      type: 'BUG',
       assigneeId: 'user-2',
     });
     expect(input).not.toHaveProperty('id');
     expect(input).not.toHaveProperty('key');
     expect(input).not.toHaveProperty('createdAt');
+    // Теги сохраняются отдельно — в issue_tag, вместе с историей
+    expect(input).not.toHaveProperty('tags');
   });
 });

src/modules/issue/infrastructure/persistence/prisma/mappers/issue.mapper.ts

@@ -2,8 +2,14 @@ import type { Issue as PrismaIssue, Prisma } from '../../../../../../generated/p
 import { Issue } from '../../../../domain/entities/issue.entity.js';
 import { getCKey } from '../../../../domain/helpers/get-ckey.js';
 
+/** Запись задачи вместе с id наблюдателей и тегами (см. WITH_RELATIONS в репозитории) */
+export type PrismaIssueWithRelations = PrismaIssue & {
+  observers: Array<{ userId: string }>;
+  tags: Array<{ tag: { id: string; name: string; color: string } }>;
+};
+
 export class IssuePrismaMapper {
-  static toDomain(record: PrismaIssue): Issue {
+  static toDomain(record: PrismaIssueWithRelations): Issue {
     return Issue.reconstitute({
       id: record.id,
       key: getCKey(record.id, record.key),
@@ -11,8 +17,11 @@ export class IssuePrismaMapper {
       content: record.content,
       status: record.status,
       priority: record.priority,
+      type: record.type,
       assignee: record.assigneeId,
       reporter: record.reporterId,
+      observers: record.observers.map((observer) => observer.userId),
+      tags: record.tags.map(({ tag }) => tag),
       projectId: record.projectId,
       dueDate: record.dueDate,
       createdAt: record.createdAt,
@@ -27,8 +36,11 @@ export class IssuePrismaMapper {
       content: issue.content,
       status: issue.status,
       priority: issue.priority,
+      type: issue.type,
       assigneeId: issue.assignee,
       reporterId: issue.reporter,
+      observers: { create: issue.observers.map((userId) => ({ userId })) },
+      tags: { create: issue.tags.map((tag) => ({ tagId: tag.id })) },
       projectId: issue.projectId,
       dueDate: issue.dueDate,
       createdAt: issue.createdAt,
@@ -42,6 +54,7 @@ export class IssuePrismaMapper {
       content: issue.content,
       status: issue.status,
       priority: issue.priority,
+      type: issue.type,
       assigneeId: issue.assignee,
       dueDate: issue.dueDate,
       updatedAt: issue.updatedAt,

src/modules/issue/infrastructure/persistence/prisma/repositories/issue.prisma-repository.ts

@@ -1,19 +1,69 @@
+import { randomUUID } from 'node:crypto';
 import { Injectable } from '@nestjs/common';
 import { PrismaAdapter } from '../../../../../../common/prisma-adapter/prisma.adapter.js';
 import { Issue } from '../../../../domain/entities/issue.entity.js';
-import { IIssueRepository } from '../../../../domain/repositories/issue.repository.interface.js';
+import { IIssueRepository, IssueUserRole } from '../../../../domain/repositories/issue.repository.interface.js';
 import { IssuePrismaMapper } from '../mappers/issue.mapper.js';
 import { IssueFindManyArgs } from '../../../../../../generated/prisma/models/Issue.js';
 import { PaginationMeta } from '../../../../../../common/interfaces/pagination-meta.interface.js';
 import { splitCKey } from '../../../../domain/helpers/get-ckey.js';
 import { Prisma } from '../../../../../../generated/prisma/client.js';
 import { IssueProjectNotFoundException } from '../../../../domain/exceptions/issue-project-not-found.exception.js';
+import type { IssueFieldChange } from '../../../../domain/entities/issue-change.js';
 
 const FOREIGN_KEY_VIOLATION = 'P2003';
 
-/** Задача видна только своему reporter/assignee */
+/** id наблюдателей и теги подгружаются вместе с задачей — они часть сущности */
-function ownedByUser(userId: string) {
+const WITH_RELATIONS = {
-  return [{ assigneeId: userId }, { reporterId: userId }];
+  observers: { select: { userId: true } },
+  tags: { select: { tag: { select: { id: true, name: true, color: true } } } },
+} satisfies Prisma.IssueInclude;
+
+/**
+ * Задача видна своим reporter, assignee и наблюдателям.
+ * То же правило — в visibleIssuesCte (history) и в SSE-фильтре IssueController.
+ */
+function visibleTo(userId: string): Prisma.IssueWhereInput[] {
+  return [{ assigneeId: userId }, { reporterId: userId }, { observers: { some: { userId } } }];
+}
+
+function roleFilter(userId: string, role: IssueUserRole): Prisma.IssueWhereInput {
+  switch (role) {
+    case 'assigned':
+      return { assigneeId: userId };
+    case 'reported':
+      return { reporterId: userId };
+    case 'observing':
+      return { observers: { some: { userId } } };
+  }
+}
+
+/** Видимость и фильтры, общие для списка и календаря */
+function commonFilters(params: {
+  userId: string;
+  status?: string[];
+  assigneeId?: string;
+  projectId?: string;
+  role?: IssueUserRole;
+}): Prisma.IssueWhereInput[] {
+  return [
+    { OR: visibleTo(params.userId) },
+    ...(params.role ? [roleFilter(params.userId, params.role)] : []),
+    ...(params.status?.length ? [{ status: { in: params.status } }] : []),
+    ...(params.assigneeId ? [{ assigneeId: params.assigneeId }] : []),
+    ...(params.projectId ? [{ projectId: params.projectId }] : []),
+  ];
+}
+
+/** Строки истории одного сохранения задачи — с общим changeId */
+function toChangeRows(
+  issueId: number,
+  changes: IssueFieldChange[],
+  actorId: string | null,
+  changedAt: Date,
+): Prisma.IssueChangeCreateManyInput[] {
+  const changeId = randomUUID();
+  return changes.map((change) => ({ issueId, changeId, actorId, changedAt, ...change }));
 }
 
 @Injectable()
@@ -22,7 +72,8 @@ export class IssuePrismaRepository implements IIssueRepository {
 
   async findById(id: number, userId: string): Promise<Issue | null> {
     const record = await this.prisma.issue.findFirst({
-      where: { id, OR: ownedByUser(userId) },
+      where: { id, OR: visibleTo(userId) },
+      include: WITH_RELATIONS,
     });
     return record ? IssuePrismaMapper.toDomain(record) : null;
   }
@@ -30,7 +81,8 @@ export class IssuePrismaRepository implements IIssueRepository {
   async findByCKey(ckey: string, userId: string): Promise<Issue | null> {
     const { id, key } = splitCKey(ckey);
     const record = await this.prisma.issue.findFirst({
-      where: { id, key, OR: ownedByUser(userId) },
+      where: { id, key, OR: visibleTo(userId) },
+      include: WITH_RELATIONS,
     });
 
     return record ? IssuePrismaMapper.toDomain(record) : null;
@@ -40,10 +92,13 @@ export class IssuePrismaRepository implements IIssueRepository {
     limit: number;
     page: number;
     userId: string;
-    status?: string;
+    status?: string[];
     text?: string;
     assigneeId?: string;
     projectId?: string;
+    hasDueDate?: boolean;
+    type?: string[];
+    role?: IssueUserRole;
   }): Promise<{ list: Issue[]; meta: PaginationMeta }> {
     const page = Math.max(1, params?.page);
     const limit = Math.max(1, params?.limit);
@@ -51,10 +106,9 @@ export class IssuePrismaRepository implements IIssueRepository {
     const queryArgs: IssueFindManyArgs = {
       where: {
         AND: [
-          { OR: ownedByUser(params.userId) },
+          ...commonFilters(params),
-          ...(params.status ? [{ status: params.status }] : []),
+          ...(params.type?.length ? [{ type: { in: params.type } }] : []),
-          ...(params.assigneeId ? [{ assigneeId: params.assigneeId }] : []),
+          ...(params.hasDueDate !== undefined ? [{ dueDate: params.hasDueDate ? { not: null } : null }] : []),
-          ...(params.projectId ? [{ projectId: params.projectId }] : []),
           ...(params.text
             ? [
                 {
@@ -72,6 +126,7 @@ export class IssuePrismaRepository implements IIssueRepository {
     const [records, totalCount] = await this.prisma.$transaction([
       this.prisma.issue.findMany({
         ...queryArgs,
+        include: WITH_RELATIONS,
         take: limit,
         skip: (page - 1) * limit,
         orderBy: { createdAt: 'desc' },
@@ -85,10 +140,31 @@ export class IssuePrismaRepository implements IIssueRepository {
     };
   }
 
+  async findByDueDateRange(params: {
+    from: Date;
+    to: Date;
+    limit: number;
+    userId: string;
+    status?: string[];
+    assigneeId?: string;
+    projectId?: string;
+  }): Promise<Issue[]> {
+    const records = await this.prisma.issue.findMany({
+      where: {
+        AND: [...commonFilters(params), { dueDate: { gte: params.from, lt: params.to } }],
+      },
+      include: WITH_RELATIONS,
+      take: Math.max(1, params.limit),
+      orderBy: [{ dueDate: 'asc' }, { id: 'asc' }],
+    });
+
+    return records.map(IssuePrismaMapper.toDomain);
+  }
+
   async countByStatus(userId: string, projectId?: string): Promise<Array<{ status: string; count: number }>> {
     const groups = await this.prisma.issue.groupBy({
       by: ['status'],
-      where: { AND: [{ OR: ownedByUser(userId) }, ...(projectId ? [{ projectId }] : [])] },
+      where: { AND: [{ OR: visibleTo(userId) }, ...(projectId ? [{ projectId }] : [])] },
       _count: { _all: true },
     });
 
@@ -96,9 +172,18 @@ export class IssuePrismaRepository implements IIssueRepository {
   }
 
   async create(issue: Issue): Promise<Issue> {
+    const changes = issue.pullChanges();
+
     try {
-      const record = await this.prisma.issue.create({
+      const record = await this.prisma.$transaction(async (tx) => {
+        const created = await tx.issue.create({
           data: IssuePrismaMapper.toCreateInput(issue),
+          include: WITH_RELATIONS,
+        });
+        await tx.issueChange.createMany({
+          data: toChangeRows(created.id, changes, issue.reporter, issue.createdAt),
+        });
+        return created;
       });
 
       return IssuePrismaMapper.toDomain(record);
@@ -110,11 +195,47 @@ export class IssuePrismaRepository implements IIssueRepository {
     }
   }
 
-  async update(issue: Issue): Promise<void> {
+  async update(issue: Issue, actorId: string): Promise<void> {
-    await this.prisma.issue.update({
+    const issueId = issue.id as number;
-      where: { id: issue.id as number },
+    const changes = issue.pullChanges();
+
+    const updateIssue = this.prisma.issue.update({
+      where: { id: issueId },
       data: IssuePrismaMapper.toUpdateInput(issue),
     });
+
+    if (changes.length === 0) {
+      await updateIssue;
+      return;
+    }
+
+    const observers = [...issue.observers];
+    const tagIds = issue.tags.map((tag) => tag.id);
+    await this.prisma.$transaction([
+      updateIssue,
+      // Наблюдатели и теги меняются только вместе с записью observer/tag в истории
+      ...(changes.some((change) => change.field === 'observer')
+        ? [
+            this.prisma.issueObserver.deleteMany({ where: { issueId, userId: { notIn: observers } } }),
+            this.prisma.issueObserver.createMany({
+              data: observers.map((userId) => ({ issueId, userId })),
+              skipDuplicates: true,
+            }),
+          ]
+        : []),
+      ...(changes.some((change) => change.field === 'tag')
+        ? [
+            this.prisma.issueTag.deleteMany({ where: { issueId, tagId: { notIn: tagIds } } }),
+            this.prisma.issueTag.createMany({
+              data: tagIds.map((tagId) => ({ issueId, tagId })),
+              skipDuplicates: true,
+            }),
+          ]
+        : []),
+      this.prisma.issueChange.createMany({
+        data: toChangeRows(issueId, changes, actorId, issue.updatedAt),
+      }),
+    ]);
   }
 
   async delete(id: number): Promise<void> {

src/modules/issue/issue.module.ts

@@ -2,6 +2,8 @@ import { Module } from '@nestjs/common';
 import { PrismaModule } from '../../common/prisma-adapter/prisma.module.js';
 import { ProjectModule } from '../project/project.module.js';
 import { UserModule } from '../user/user.module.js';
+import { NotificationModule } from '../notification/notification.module.js';
+import { TagModule } from '../tag/tag.module.js';
 import { IssuePrismaRepository } from './infrastructure/persistence/prisma/repositories/issue.prisma-repository.js';
 import { ISSUE_REPOSITORY } from './domain/repositories/issue.repository.interface.js';
 import { IssueController } from './presentation/controllers/issue.controller.js';
@@ -14,10 +16,14 @@ import { IssueResolver } from './presentation/resolvers/issue.resolver.js';
 import { GetIssueByCkeyUseCase } from './application/use-cases/get-issue-by-ckey/get-issue-by-ckey.use-case.js';
 import { IssueEventsService } from './application/services/issue-events.service.js';
 import { IssueUserExpanderService } from './application/services/issue-user-expander.service.js';
+import { IssueAssignmentNotifierService } from './application/services/issue-assignment-notifier.service.js';
 import { GetIssueStatsUseCase } from './application/use-cases/get-issue-stats/get-issue-stats.use-case.js';
+import { ListCalendarIssuesUseCase } from './application/use-cases/list-calendar-issues/list-calendar-issues.use-case.js';
+import { UnobserveIssueUseCase } from './application/use-cases/unobserve-issue/unobserve-issue.use-case.js';
+import { IssueParticipantsService } from './application/services/issue-participants.service.js';
 
 @Module({
-  imports: [PrismaModule, ProjectModule, UserModule],
+  imports: [PrismaModule, ProjectModule, UserModule, NotificationModule, TagModule],
   controllers: [IssueController],
   providers: [
     CreateIssueUseCase,
@@ -27,9 +33,13 @@ import { GetIssueStatsUseCase } from './application/use-cases/get-issue-stats/ge
     UpdateIssueUseCase,
     DeleteIssueUseCase,
     GetIssueStatsUseCase,
+    ListCalendarIssuesUseCase,
+    UnobserveIssueUseCase,
     IssueResolver,
     IssueEventsService,
     IssueUserExpanderService,
+    IssueAssignmentNotifierService,
+    IssueParticipantsService,
     {
       // Domain видит только интерфейс IIssueRepository,
       // конкретную реализацию (Prisma) подставляет DI-контейнер здесь

src/modules/issue/presentation/controllers/issue.controller.ts

@@ -1,7 +1,9 @@
 import {
+  BadRequestException,
   Body,
   Controller,
   Delete,
+  ForbiddenException,
   Get,
   HttpCode,
   HttpStatus,
@@ -37,6 +39,15 @@ import { GetIssueByCkeyUseCase } from '../../application/use-cases/get-issue-by-
 import { GetIssueByCkeyQuery } from '../../application/use-cases/get-issue-by-ckey/get-issue-by-ckey.query.js';
 import { IssueEventsService } from '../../application/services/issue-events.service.js';
 import { GetIssueStatsUseCase } from '../../application/use-cases/get-issue-stats/get-issue-stats.use-case.js';
+import { ListCalendarIssuesUseCase } from '../../application/use-cases/list-calendar-issues/list-calendar-issues.use-case.js';
+import { ListCalendarIssuesQuery } from '../../application/use-cases/list-calendar-issues/list-calendar-issues.query.js';
+import { CalendarIssuesQueryDto } from '../dto/calendar-issues-query.dto.js';
+import { InvalidCalendarRangeException } from '../../domain/exceptions/invalid-calendar-range.exception.js';
+import { IssueEditForbiddenException } from '../../domain/exceptions/issue-edit-forbidden.exception.js';
+import { IssueProjectForbiddenException } from '../../domain/exceptions/issue-project-forbidden.exception.js';
+import { IssueObserverNotFoundException } from '../../domain/exceptions/issue-observer-not-found.exception.js';
+import { UnobserveIssueUseCase } from '../../application/use-cases/unobserve-issue/unobserve-issue.use-case.js';
+import { UnobserveIssueCommand } from '../../application/use-cases/unobserve-issue/unobserve-issue.command.js';
 
 @Controller('issues')
 export class IssueController {
@@ -48,6 +59,8 @@ export class IssueController {
     private readonly updateIssueUseCase: UpdateIssueUseCase,
     private readonly deleteIssueUseCase: DeleteIssueUseCase,
     private readonly getIssueStatsUseCase: GetIssueStatsUseCase,
+    private readonly listCalendarIssuesUseCase: ListCalendarIssuesUseCase,
+    private readonly unobserveIssueUseCase: UnobserveIssueUseCase,
     private readonly issueEventsService: IssueEventsService,
   ) {}
 
@@ -64,6 +77,9 @@ export class IssueController {
           dto.priority,
           dto.assignee,
           dto.dueDate !== undefined ? new Date(dto.dueDate) : undefined,
+          dto.type,
+          dto.observers,
+          dto.tags,
         ),
       ),
     );
@@ -80,6 +96,26 @@ export class IssueController {
         query.status,
         query.text,
         query.assigneeId,
+        query.hasDueDate,
+        query.type,
+        query.role,
+      ),
+    );
+  }
+
+  /** Задачи с dueDate в [from, to) — для календаря, без пагинации */
+  @Get('calendar')
+  calendar(@Query() query: CalendarIssuesQueryDto, @Session() session: UserSession) {
+    return this.handleErrors(() =>
+      this.listCalendarIssuesUseCase.execute(
+        new ListCalendarIssuesQuery(
+          session.user.id,
+          new Date(query.from),
+          new Date(query.to),
+          query.projectId,
+          query.status,
+          query.assigneeId,
+        ),
       ),
     );
   }
@@ -92,13 +128,15 @@ export class IssueController {
   /**
    * SSE-поток для зарегистрированных пользователей (доступ уже проверен
    * глобальным AuthGuard): уведомляет о каждой созданной, обновлённой
-   * и удалённой задаче, видимой текущему пользователю (reporter/assignee —
+   * и удалённой задаче, видимой текущему пользователю (reporter/assignee/наблюдатель —
-   * то же правило видимости, что и в IssuePrismaRepository.ownedByUser).
+   * то же правило видимости, что и в IssuePrismaRepository.visibleTo).
    */
   @Sse('events')
   issueCreatedEvents(@Session() session: UserSession): Observable<MessageEvent> {
     const isVisibleToUser = (issue: IssueDto) =>
-      issue.reporterId === session.user.id || issue.assigneeId === session.user.id;
+      issue.reporterId === session.user.id ||
+      issue.assigneeId === session.user.id ||
+      issue.observerIds.includes(session.user.id);
 
     return merge(
       this.issueEventsService.onIssueCreated().pipe(
@@ -143,6 +181,9 @@ export class IssueController {
           dto.priority,
           dto.assignee,
           dto.dueDate === undefined ? undefined : dto.dueDate === null ? null : new Date(dto.dueDate),
+          dto.type,
+          dto.observers,
+          dto.tags,
         ),
       ),
     );
@@ -154,6 +195,13 @@ export class IssueController {
     await this.handleErrors(() => this.deleteIssueUseCase.execute(new DeleteIssueCommand(id, session.user.id)));
   }
 
+  /** Наблюдатель отписывается от задачи сам (снять других может только reporter/assignee через PATCH) */
+  @Delete(':id/observers/me')
+  @HttpCode(HttpStatus.NO_CONTENT)
+  async unobserve(@Param('id', ParseIntPipe) id: number, @Session() session: UserSession) {
+    await this.handleErrors(() => this.unobserveIssueUseCase.execute(new UnobserveIssueCommand(id, session.user.id)));
+  }
+
   /** Транслирует доменные исключения в HTTP-ответ — это забота presentation-слоя */
   private async handleErrors<T>(fn: () => Promise<T>): Promise<T> {
     try {
@@ -162,6 +210,12 @@ export class IssueController {
       if (error instanceof IssueNotFoundException || error instanceof IssueProjectNotFoundException) {
         throw new NotFoundException(error.message);
       }
+      if (error instanceof InvalidCalendarRangeException || error instanceof IssueObserverNotFoundException) {
+        throw new BadRequestException(error.message);
+      }
+      if (error instanceof IssueEditForbiddenException || error instanceof IssueProjectForbiddenException) {
+        throw new ForbiddenException(error.message);
+      }
       throw error;
     }
   }

src/modules/issue/presentation/dto/calendar-issues-query.dto.spec.ts

@@ -0,0 +1,46 @@
+import { describe, expect, it } from 'vitest';
+import { plainToInstance } from 'class-transformer';
+import { validateSync } from 'class-validator';
+import { CalendarIssuesQueryDto } from './calendar-issues-query.dto.js';
+
+const parse = (query: Record<string, unknown>) => {
+  const dto = plainToInstance(CalendarIssuesQueryDto, query);
+  return { dto, errors: validateSync(dto) };
+};
+
+describe('CalendarIssuesQueryDto', () => {
+  it('accepts moments with an offset or Z', () => {
+    const { errors } = parse({ from: '2026-09-28T00:00:00+03:00', to: '2026-11-09T00:00:00.000Z' });
+
+    expect(errors).toHaveLength(0);
+  });
+
+  it('requires from and to', () => {
+    const { errors } = parse({});
+
+    expect(errors.map((el) => el.property)).toEqual(['from', 'to']);
+  });
+
+  it('rejects a moment without an offset', () => {
+    const { errors } = parse({ from: '2026-09-28T00:00:00', to: '2026-11-09T00:00:00Z' });
+
+    expect(errors.map((el) => el.property)).toEqual(['from']);
+  });
+
+  it('rejects a plain date', () => {
+    const { errors } = parse({ from: '2026-09-28', to: '2026-11-09T00:00:00Z' });
+
+    expect(errors.map((el) => el.property)).toEqual(['from']);
+  });
+
+  it('parses the status list', () => {
+    const { dto, errors } = parse({
+      from: '2026-09-28T00:00:00Z',
+      to: '2026-11-09T00:00:00Z',
+      status: 'OPEN,IN_PROGRESS',
+    });
+
+    expect(dto.status).toEqual(['OPEN', 'IN_PROGRESS']);
+    expect(errors).toHaveLength(0);
+  });
+});

src/modules/issue/presentation/dto/calendar-issues-query.dto.ts

@@ -0,0 +1,28 @@
+import { IsISO8601, Matches } from 'class-validator';
+import { StringDecorator } from '../../../../common/decorators/validators.js';
+import { IssueStatusListDecorator } from './issue-alias-list.decorator.js';
+
+/** Без смещения дата трактовалась бы в часовом поясе сервера */
+const WITH_OFFSET = /(Z|[+-]\d{2}:\d{2})$/;
+const MOMENT_MESSAGE = '$property: ожидается ISO 8601 со смещением, например 2026-10-01T00:00:00+03:00';
+
+export class CalendarIssuesQueryDto {
+  /** Начало видимой сетки календаря, включительно */
+  @IsISO8601({ strict: true }, { message: MOMENT_MESSAGE })
+  @Matches(WITH_OFFSET, { message: MOMENT_MESSAGE })
+  from: string;
+
+  /** Конец видимой сетки календаря, не включительно */
+  @IsISO8601({ strict: true }, { message: MOMENT_MESSAGE })
+  @Matches(WITH_OFFSET, { message: MOMENT_MESSAGE })
+  to: string;
+
+  @StringDecorator({ isOptional: true })
+  projectId?: string;
+
+  @StringDecorator({ isOptional: true })
+  assigneeId?: string;
+
+  @IssueStatusListDecorator()
+  status?: string[];
+}

src/modules/issue/presentation/dto/create-issue.dto.ts

@@ -1,4 +1,20 @@
-import { IsDateString, IsInt, IsNotEmpty, IsOptional, IsString, Max, MaxLength, Min } from 'class-validator';
+import {
+  ArrayMaxSize,
+  IsArray,
+  IsDateString,
+  IsIn,
+  IsInt,
+  IsNotEmpty,
+  IsOptional,
+  IsString,
+  Matches,
+  Max,
+  MaxLength,
+  Min,
+} from 'class-validator';
+import { ISSUE_TYPE_ALIASES } from '../../domain/value-objects/issue-type.vo.js';
+import { ISSUE_TAGS_MAX_COUNT } from '../../domain/value-objects/issue-tags.vo.js';
+import { TAG_NAME_MAX_LENGTH } from '../../../tag/domain/value-objects/tag-name.vo.js';
 
 export class CreateIssueRequestDto {
   @IsString()
@@ -24,6 +40,10 @@ export class CreateIssueRequestDto {
   @Max(4)
   priority?: number;
 
+  @IsOptional()
+  @IsIn(ISSUE_TYPE_ALIASES)
+  type?: string;
+
   @IsOptional()
   @IsString()
   assignee?: string;
@@ -31,4 +51,20 @@ export class CreateIssueRequestDto {
   @IsOptional()
   @IsDateString()
   dueDate?: string;
+
+  /** id пользователей-наблюдателей: видят задачу и комментируют, но не редактируют */
+  @IsOptional()
+  @IsArray()
+  @ArrayMaxSize(50)
+  @IsString({ each: true })
+  observers?: string[];
+
+  /** Имена тегов; отсутствующие в справочнике проекта создаются, регистр не различается */
+  @IsOptional()
+  @IsArray()
+  @ArrayMaxSize(ISSUE_TAGS_MAX_COUNT)
+  @IsString({ each: true })
+  @Matches(/\S/, { each: true, message: 'tags не может содержать пустых имён' })
+  @MaxLength(TAG_NAME_MAX_LENGTH, { each: true })
+  tags?: string[];
 }

src/modules/issue/presentation/dto/filter-issue.dto.spec.ts

@@ -0,0 +1,76 @@
+import { describe, expect, it } from 'vitest';
+import { plainToInstance } from 'class-transformer';
+import { validateSync } from 'class-validator';
+import { FilterIssueDto } from './filter-issue.dto.js';
+
+const parse = (query: Record<string, unknown>) => {
+  const dto = plainToInstance(FilterIssueDto, query);
+  return { dto, errors: validateSync(dto) };
+};
+
+describe('FilterIssueDto.status', () => {
+  it('leaves status undefined when absent', () => {
+    const { dto, errors } = parse({});
+
+    expect(dto.status).toBeUndefined();
+    expect(errors).toHaveLength(0);
+  });
+
+  it('wraps a single status into an array', () => {
+    const { dto, errors } = parse({ status: 'OPEN' });
+
+    expect(dto.status).toEqual(['OPEN']);
+    expect(errors).toHaveLength(0);
+  });
+
+  it('splits a comma-separated list', () => {
+    const { dto, errors } = parse({ status: 'OPEN, IN_PROGRESS' });
+
+    expect(dto.status).toEqual(['OPEN', 'IN_PROGRESS']);
+    expect(errors).toHaveLength(0);
+  });
+
+  it('accepts a repeated query param', () => {
+    const { dto, errors } = parse({ status: ['OPEN', 'DONE'] });
+
+    expect(dto.status).toEqual(['OPEN', 'DONE']);
+    expect(errors).toHaveLength(0);
+  });
+
+  it('rejects an unknown status', () => {
+    const { errors } = parse({ status: 'OPEN,UNKNOWN' });
+
+    expect(errors.map((el) => el.property)).toEqual(['status']);
+  });
+
+  it('rejects an empty value', () => {
+    const { errors } = parse({ status: '' });
+
+    expect(errors.map((el) => el.property)).toEqual(['status']);
+  });
+});
+
+describe('FilterIssueDto.hasDueDate', () => {
+  it('leaves hasDueDate undefined when absent', () => {
+    const { dto, errors } = parse({});
+
+    expect(dto.hasDueDate).toBeUndefined();
+    expect(errors).toHaveLength(0);
+  });
+
+  it.each([
+    ['true', true],
+    ['false', false],
+  ])('parses "%s"', (value, expected) => {
+    const { dto, errors } = parse({ hasDueDate: value });
+
+    expect(dto.hasDueDate).toBe(expected);
+    expect(errors).toHaveLength(0);
+  });
+
+  it('rejects a non-boolean value', () => {
+    const { errors } = parse({ hasDueDate: 'yes' });
+
+    expect(errors.map((el) => el.property)).toEqual(['hasDueDate']);
+  });
+});