feat: add repository pattern validation (v0.5.0)

Add comprehensive Repository Pattern validation to detect violations
and ensure proper domain-infrastructure separation.

Features:
- ORM type detection in repository interfaces (25+ patterns)
- Concrete repository usage detection in use cases
- Repository instantiation detection (new Repository())
- Domain language validation for repository methods
- Smart violation reporting with fix suggestions

Tests:
- 31 new tests for repository pattern detection
- 292 total tests passing (100% pass rate)
- 96.77% statement coverage, 83.82% branch coverage

Examples:
- 8 example files (4 bad patterns, 4 good patterns)
- Demonstrates Clean Architecture and SOLID principles

packages/guardian/examples/bad-architecture/dependency-direction/BadApplicationLayer.ts

@@ -0,0 +1,117 @@
+/**
+ * ❌ BAD: Application layer with incorrect dependencies
+ *
+ * Application importing from Infrastructure layer
+ * This violates Clean Architecture dependency rules!
+ */
+
+import { User } from "../../good-architecture/domain/entities/User"
+import { Email } from "../../good-architecture/domain/value-objects/Email"
+import { UserId } from "../../good-architecture/domain/value-objects/UserId"
+
+/**
+ * ❌ VIOLATION: Application importing from Infrastructure layer
+ */
+import { PrismaClient } from "@prisma/client"
+
+export class CreateUser {
+    /**
+     * ❌ VIOLATION: Application use case depending on concrete infrastructure (Prisma)
+     */
+    constructor(private prisma: PrismaClient) {}
+
+    async execute(email: string): Promise<User> {
+        const userId = UserId.generate()
+        const emailVO = Email.create(email).value
+
+        /**
+         * ❌ VIOLATION: Application logic directly accessing database
+         */
+        await this.prisma.user.create({
+            data: {
+                id: userId.getValue(),
+                email: emailVO.getValue(),
+            },
+        })
+
+        return new User(userId, emailVO)
+    }
+}
+
+/**
+ * ❌ VIOLATION: Application importing concrete email service from infrastructure
+ */
+import { SmtpEmailService } from "../../good-architecture/infrastructure/adapters/SmtpEmailService"
+
+export class SendWelcomeEmail {
+    /**
+     * ❌ VIOLATION: Application depending on concrete infrastructure implementation
+     * Should depend on IEmailService interface instead
+     */
+    constructor(
+        private prisma: PrismaClient,
+        private emailService: SmtpEmailService,
+    ) {}
+
+    async execute(userId: string): Promise<void> {
+        const user = await this.prisma.user.findUnique({
+            where: { id: userId },
+        })
+
+        if (!user) {
+            throw new Error("User not found")
+        }
+
+        await this.emailService.sendWelcomeEmail(user.email)
+    }
+}
+
+/**
+ * ❌ VIOLATION: Application importing from infrastructure controller
+ */
+import { UserController } from "../../good-architecture/infrastructure/controllers/UserController"
+
+export class ValidateUser {
+    /**
+     * ❌ VIOLATION: Application use case depending on infrastructure controller
+     * The dependency direction is completely wrong!
+     */
+    constructor(private userController: UserController) {}
+
+    async execute(userId: string): Promise<boolean> {
+        return true
+    }
+}
+
+/**
+ * ❌ VIOLATION: Application importing HTTP framework
+ */
+import express from "express"
+
+export class ProcessUserRequest {
+    /**
+     * ❌ VIOLATION: Application layer knows about HTTP/Express
+     * HTTP concerns should be in infrastructure layer
+     */
+    async execute(req: express.Request): Promise<void> {
+        const email = req.body.email
+        console.log(`Processing user: ${email}`)
+    }
+}
+
+/**
+ * ❌ VIOLATION: Application importing infrastructure repository implementation
+ */
+import { InMemoryUserRepository } from "../../good-architecture/infrastructure/repositories/InMemoryUserRepository"
+
+export class GetUser {
+    /**
+     * ❌ VIOLATION: Application depending on concrete repository implementation
+     * Should depend on IUserRepository interface from domain
+     */
+    constructor(private userRepo: InMemoryUserRepository) {}
+
+    async execute(userId: string): Promise<User | null> {
+        return await this.userRepo.findById(UserId.from(userId))
+    }
+}

packages/guardian/examples/bad-architecture/dependency-direction/BadDomainLayer.ts

@@ -0,0 +1,90 @@
+/**
+ * ❌ BAD: Domain layer with incorrect dependencies
+ *
+ * Domain importing from Application and Infrastructure layers
+ * This violates Clean Architecture dependency rules!
+ */
+
+import { Email } from "../../good-architecture/domain/value-objects/Email"
+import { UserId } from "../../good-architecture/domain/value-objects/UserId"
+
+/**
+ * ❌ VIOLATION: Domain importing from Application layer
+ */
+import { UserResponseDto } from "../../good-architecture/application/dtos/UserResponseDto"
+
+export class User {
+    private readonly id: UserId
+    private email: Email
+
+    constructor(id: UserId, email: Email) {
+        this.id = id
+        this.email = email
+    }
+
+    /**
+     * ❌ VIOLATION: Domain entity returning DTO from application layer
+     */
+    toDto(): UserResponseDto {
+        return {
+            id: this.id.getValue(),
+            email: this.email.getValue(),
+            createdAt: new Date().toISOString(),
+        }
+    }
+}
+
+/**
+ * ❌ VIOLATION: Domain importing from Infrastructure layer
+ */
+import { PrismaClient } from "@prisma/client"
+
+export class UserService {
+    /**
+     * ❌ VIOLATION: Domain service depending on concrete infrastructure implementation
+     */
+    constructor(private prisma: PrismaClient) {}
+
+    async createUser(email: string): Promise<User> {
+        const userId = UserId.generate()
+        const emailVO = Email.create(email).value
+
+        /**
+         * ❌ VIOLATION: Domain logic directly accessing database
+         */
+        await this.prisma.user.create({
+            data: {
+                id: userId.getValue(),
+                email: emailVO.getValue(),
+            },
+        })
+
+        return new User(userId, emailVO)
+    }
+}
+
+/**
+ * ❌ VIOLATION: Domain importing email service from infrastructure
+ */
+import { SmtpEmailService } from "../../good-architecture/infrastructure/adapters/SmtpEmailService"
+
+export class UserRegistration {
+    /**
+     * ❌ VIOLATION: Domain depending on infrastructure email service
+     */
+    constructor(
+        private userService: UserService,
+        private emailService: SmtpEmailService,
+    ) {}
+
+    async register(email: string): Promise<User> {
+        const user = await this.userService.createUser(email)
+
+        /**
+         * ❌ VIOLATION: Domain calling infrastructure service directly
+         */
+        await this.emailService.sendWelcomeEmail(email)
+
+        return user
+    }
+}

packages/guardian/examples/bad-architecture/entity-exposure/infrastructure/controllers/BadOrderController.ts

@@ -0,0 +1,33 @@
+// ❌ BAD: Exposing domain entity Order in API response
+
+class Order {
+    constructor(
+        public id: string,
+        public items: OrderItem[],
+        public total: number,
+        public customerId: string,
+    ) {}
+}
+
+class OrderItem {
+    constructor(
+        public productId: string,
+        public quantity: number,
+        public price: number,
+    ) {}
+}
+
+class BadOrderController {
+    async getOrder(orderId: string): Promise<Order> {
+        return {
+            id: orderId,
+            items: [],
+            total: 100,
+            customerId: "customer-123",
+        }
+    }
+
+    async listOrders(): Promise<Order[]> {
+        return []
+    }
+}

packages/guardian/examples/good-architecture/dependency-direction/GoodApplicationLayer.ts

@@ -0,0 +1,91 @@
+/**
+ * ✅ GOOD: Application layer with correct dependencies
+ *
+ * Application should only import from:
+ * - Domain layer
+ * - Other application files
+ * - Shared utilities
+ *
+ * Application should NOT import from:
+ * - Infrastructure layer
+ */
+
+import { User } from "../domain/entities/User"
+import { Email } from "../domain/value-objects/Email"
+import { UserId } from "../domain/value-objects/UserId"
+import { IUserRepository } from "../domain/repositories/IUserRepository"
+import { Result } from "../../../src/shared/types/Result"
+
+/**
+ * ✅ Use case depends on domain interfaces (IUserRepository)
+ * NOT on infrastructure implementations
+ */
+export class CreateUser {
+    constructor(private readonly userRepo: IUserRepository) {}
+
+    async execute(request: CreateUserRequest): Promise<Result<UserResponseDto>> {
+        const emailResult = Email.create(request.email)
+        if (emailResult.isFailure) {
+            return Result.fail(emailResult.error)
+        }
+
+        const userId = UserId.generate()
+        const user = new User(userId, emailResult.value)
+
+        await this.userRepo.save(user)
+
+        return Result.ok(UserMapper.toDto(user))
+    }
+}
+
+/**
+ * ✅ DTO in application layer
+ */
+export interface CreateUserRequest {
+    email: string
+    name: string
+}
+
+export interface UserResponseDto {
+    id: string
+    email: string
+    createdAt: string
+}
+
+/**
+ * ✅ Mapper in application layer converting domain to DTO
+ */
+export class UserMapper {
+    static toDto(user: User): UserResponseDto {
+        return {
+            id: user.getId().getValue(),
+            email: user.getEmail().getValue(),
+            createdAt: user.getCreatedAt().toISOString(),
+        }
+    }
+}
+
+/**
+ * ✅ Application defines Port (interface) for email service
+ * Infrastructure will provide the Adapter (implementation)
+ */
+export interface IEmailService {
+    sendWelcomeEmail(email: string): Promise<void>
+}
+
+export class SendWelcomeEmail {
+    constructor(
+        private readonly userRepo: IUserRepository,
+        private readonly emailService: IEmailService,
+    ) {}
+
+    async execute(userId: string): Promise<Result<void>> {
+        const user = await this.userRepo.findById(UserId.from(userId))
+        if (!user) {
+            return Result.fail("User not found")
+        }
+
+        await this.emailService.sendWelcomeEmail(user.getEmail().getValue())
+        return Result.ok()
+    }
+}

packages/guardian/examples/good-architecture/dependency-direction/GoodDomainLayer.ts

@@ -0,0 +1,56 @@
+/**
+ * ✅ GOOD: Domain layer with correct dependencies
+ *
+ * Domain should only import from:
+ * - Other domain files
+ * - Shared utilities
+ *
+ * Domain should NOT import from:
+ * - Application layer
+ * - Infrastructure layer
+ */
+
+import { Email } from "../domain/value-objects/Email"
+import { UserId } from "../domain/value-objects/UserId"
+import { Result } from "../../../src/shared/types/Result"
+
+/**
+ * ✅ Domain entity using only domain value objects and shared types
+ */
+export class User {
+    private readonly id: UserId
+    private email: Email
+    private readonly createdAt: Date
+
+    constructor(id: UserId, email: Email, createdAt: Date = new Date()) {
+        this.id = id
+        this.email = email
+        this.createdAt = createdAt
+    }
+
+    public getId(): UserId {
+        return this.id
+    }
+
+    public getEmail(): Email {
+        return this.email
+    }
+
+    public changeEmail(newEmail: Email): Result<void> {
+        if (this.email.equals(newEmail)) {
+            return Result.fail("Email is the same")
+        }
+
+        this.email = newEmail
+        return Result.ok()
+    }
+}
+
+/**
+ * ✅ Domain repository interface (not importing from infrastructure)
+ */
+export interface IUserRepository {
+    findById(id: UserId): Promise<User | null>
+    save(user: User): Promise<void>
+    delete(id: UserId): Promise<void>
+}

packages/guardian/examples/good-architecture/dependency-direction/GoodInfrastructureLayer.ts

@@ -0,0 +1,128 @@
+/**
+ * ✅ GOOD: Infrastructure layer with correct dependencies
+ *
+ * Infrastructure CAN import from:
+ * - Domain layer
+ * - Application layer
+ * - Other infrastructure files
+ * - Shared utilities
+ * - External libraries (ORM, frameworks, etc.)
+ */
+
+import { User } from "../domain/entities/User"
+import { UserId } from "../domain/value-objects/UserId"
+import { Email } from "../domain/value-objects/Email"
+import { IUserRepository } from "../domain/repositories/IUserRepository"
+import { CreateUser } from "../application/use-cases/CreateUser"
+import { UserResponseDto } from "../application/dtos/UserResponseDto"
+import { IEmailService } from "../application/ports/IEmailService"
+
+/**
+ * ✅ Infrastructure implements domain interface
+ */
+export class InMemoryUserRepository implements IUserRepository {
+    private users: Map<string, User> = new Map()
+
+    async findById(id: UserId): Promise<User | null> {
+        return this.users.get(id.getValue()) ?? null
+    }
+
+    async save(user: User): Promise<void> {
+        this.users.set(user.getId().getValue(), user)
+    }
+
+    async delete(id: UserId): Promise<void> {
+        this.users.delete(id.getValue())
+    }
+}
+
+/**
+ * ✅ Infrastructure provides Adapter implementing application Port
+ */
+export class SmtpEmailService implements IEmailService {
+    constructor(
+        private readonly host: string,
+        private readonly port: number,
+    ) {}
+
+    async sendWelcomeEmail(email: string): Promise<void> {
+        console.log(`Sending welcome email to ${email} via SMTP`)
+    }
+}
+
+/**
+ * ✅ Controller uses application use cases and DTOs
+ */
+export class UserController {
+    constructor(private readonly createUser: CreateUser) {}
+
+    async create(request: { email: string; name: string }): Promise<UserResponseDto> {
+        const result = await this.createUser.execute(request)
+
+        if (result.isFailure) {
+            throw new Error(result.error)
+        }
+
+        return result.value
+    }
+}
+
+/**
+ * ✅ Infrastructure can use external frameworks
+ */
+import express from "express"
+
+export class ExpressServer {
+    private app = express()
+
+    constructor(private readonly userController: UserController) {
+        this.setupRoutes()
+    }
+
+    private setupRoutes(): void {
+        this.app.post("/users", async (req, res) => {
+            const user = await this.userController.create(req.body)
+            res.json(user)
+        })
+    }
+}
+
+/**
+ * ✅ Infrastructure can use ORM
+ */
+import { PrismaClient } from "@prisma/client"
+
+export class PrismaUserRepository implements IUserRepository {
+    constructor(private readonly prisma: PrismaClient) {}
+
+    async findById(id: UserId): Promise<User | null> {
+        const userData = await this.prisma.user.findUnique({
+            where: { id: id.getValue() },
+        })
+
+        if (!userData) {
+            return null
+        }
+
+        return new User(UserId.from(userData.id), Email.create(userData.email).value)
+    }
+
+    async save(user: User): Promise<void> {
+        await this.prisma.user.upsert({
+            where: { id: user.getId().getValue() },
+            create: {
+                id: user.getId().getValue(),
+                email: user.getEmail().getValue(),
+            },
+            update: {
+                email: user.getEmail().getValue(),
+            },
+        })
+    }
+
+    async delete(id: UserId): Promise<void> {
+        await this.prisma.user.delete({
+            where: { id: id.getValue() },
+        })
+    }
+}

packages/guardian/examples/good-architecture/entity-exposure/GoodUserController.ts

@@ -0,0 +1,42 @@
+// ✅ GOOD: Using DTOs and Mappers instead of exposing domain entities
+
+class User {
+    constructor(
+        private readonly id: string,
+        private email: string,
+        private password: string,
+    ) {}
+
+    getId(): string {
+        return this.id
+    }
+
+    getEmail(): string {
+        return this.email
+    }
+}
+
+class UserResponseDto {
+    constructor(
+        public readonly id: string,
+        public readonly email: string,
+    ) {}
+}
+
+class UserMapper {
+    static toDto(user: User): UserResponseDto {
+        return new UserResponseDto(user.getId(), user.getEmail())
+    }
+}
+
+class GoodUserController {
+    async getUser(userId: string): Promise<UserResponseDto> {
+        const user = new User(userId, "user@example.com", "hashed-password")
+        return UserMapper.toDto(user)
+    }
+
+    async listUsers(): Promise<UserResponseDto[]> {
+        const users = [new User("1", "user1@example.com", "password")]
+        return users.map((user) => UserMapper.toDto(user))
+    }
+}

packages/guardian/examples/repository-pattern/README.md

@@ -0,0 +1,220 @@
+# Repository Pattern Examples
+
+This directory contains examples demonstrating proper and improper implementations of the Repository Pattern.
+
+## Overview
+
+The Repository Pattern provides an abstraction layer between domain logic and data access. A well-implemented repository:
+
+1. Uses domain types, not ORM-specific types
+2. Depends on interfaces, not concrete implementations
+3. Uses dependency injection, not direct instantiation
+4. Uses domain language, not technical database terms
+
+## Examples
+
+### ❌ Bad Examples
+
+#### 1. ORM Types in Interface
+**File:** `bad-orm-types-in-interface.ts`
+
+**Problem:** Repository interface exposes Prisma-specific types (`Prisma.UserWhereInput`, `Prisma.UserCreateInput`). This couples the domain layer to infrastructure concerns.
+
+**Violations:**
+- Domain depends on ORM library
+- Cannot swap ORM without changing domain
+- Breaks Clean Architecture principles
+
+#### 2. Concrete Repository in Use Case
+**File:** `bad-concrete-repository-in-use-case.ts`
+
+**Problem:** Use case depends on `PrismaUserRepository` instead of `IUserRepository` interface.
+
+**Violations:**
+- Violates Dependency Inversion Principle
+- Cannot easily mock for testing
+- Tightly coupled to specific implementation
+
+#### 3. Creating Repository with 'new'
+**File:** `bad-new-repository.ts`
+
+**Problem:** Use case instantiates repositories with `new UserRepository()` instead of receiving them through constructor.
+
+**Violations:**
+- Violates Dependency Injection principle
+- Hard to test (cannot mock dependencies)
+- Hidden dependencies
+- Creates tight coupling
+
+#### 4. Technical Method Names
+**File:** `bad-technical-method-names.ts`
+
+**Problem:** Repository methods use database/SQL terminology (`findOne`, `insert`, `query`, `execute`).
+
+**Violations:**
+- Uses technical terms instead of domain language
+- Exposes implementation details
+- Not aligned with ubiquitous language
+
+### ✅ Good Examples
+
+#### 1. Clean Interface
+**File:** `good-clean-interface.ts`
+
+**Benefits:**
+- Uses only domain types (UserId, Email, User)
+- ORM-agnostic interface
+- Easy to understand and maintain
+- Follows Clean Architecture
+
+```typescript
+interface IUserRepository {
+    findById(id: UserId): Promise<User | null>
+    findByEmail(email: Email): Promise<User | null>
+    save(user: User): Promise<void>
+    delete(id: UserId): Promise<void>
+}
+```
+
+#### 2. Interface in Use Case
+**File:** `good-interface-in-use-case.ts`
+
+**Benefits:**
+- Depends on interface, not concrete class
+- Easy to test with mocks
+- Can swap implementations
+- Follows Dependency Inversion Principle
+
+```typescript
+class CreateUser {
+    constructor(private readonly userRepo: IUserRepository) {}
+
+    async execute(data: CreateUserRequest): Promise<UserResponseDto> {
+        // Uses interface, not concrete implementation
+    }
+}
+```
+
+#### 3. Dependency Injection
+**File:** `good-dependency-injection.ts`
+
+**Benefits:**
+- All dependencies injected through constructor
+- Explicit dependencies (no hidden coupling)
+- Easy to test with mocks
+- Follows SOLID principles
+
+```typescript
+class CreateUser {
+    constructor(
+        private readonly userRepo: IUserRepository,
+        private readonly emailService: IEmailService
+    ) {}
+}
+```
+
+#### 4. Domain Language
+**File:** `good-domain-language.ts`
+
+**Benefits:**
+- Methods use business-oriented names
+- Self-documenting interface
+- Aligns with ubiquitous language
+- Hides implementation details
+
+```typescript
+interface IUserRepository {
+    findById(id: UserId): Promise<User | null>
+    findByEmail(email: Email): Promise<User | null>
+    findActiveUsers(): Promise<User[]>
+    save(user: User): Promise<void>
+    search(criteria: UserSearchCriteria): Promise<User[]>
+}
+```
+
+## Key Principles
+
+### 1. Persistence Ignorance
+Domain entities and repositories should not know about how data is persisted.
+
+```typescript
+// ❌ Bad: Domain knows about Prisma
+interface IUserRepository {
+    find(query: Prisma.UserWhereInput): Promise<User>
+}
+
+// ✅ Good: Domain uses own types
+interface IUserRepository {
+    findById(id: UserId): Promise<User | null>
+}
+```
+
+### 2. Dependency Inversion
+High-level modules (use cases) should not depend on low-level modules (repositories). Both should depend on abstractions (interfaces).
+
+```typescript
+// ❌ Bad: Use case depends on concrete repository
+class CreateUser {
+    constructor(private repo: PrismaUserRepository) {}
+}
+
+// ✅ Good: Use case depends on interface
+class CreateUser {
+    constructor(private repo: IUserRepository) {}
+}
+```
+
+### 3. Dependency Injection
+Don't create dependencies inside classes. Inject them through constructor.
+
+```typescript
+// ❌ Bad: Creates dependency
+class CreateUser {
+    execute() {
+        const repo = new UserRepository()
+    }
+}
+
+// ✅ Good: Injects dependency
+class CreateUser {
+    constructor(private readonly repo: IUserRepository) {}
+}
+```
+
+### 4. Ubiquitous Language
+Use domain language everywhere, including repository methods.
+
+```typescript
+// ❌ Bad: Technical terminology
+interface IUserRepository {
+    findOne(id: string): Promise<User>
+    insert(user: User): Promise<void>
+}
+
+// ✅ Good: Domain language
+interface IUserRepository {
+    findById(id: UserId): Promise<User | null>
+    save(user: User): Promise<void>
+}
+```
+
+## Testing with Guardian
+
+Run Guardian to detect Repository Pattern violations:
+
+```bash
+guardian check --root ./examples/repository-pattern
+```
+
+Guardian will detect:
+- ORM types in repository interfaces
+- Concrete repository usage in use cases
+- Repository instantiation with 'new'
+- Technical method names in repositories
+
+## Further Reading
+
+- [Clean Architecture by Robert C. Martin](https://blog.cleancoder.com/uncle-bob/2012/08/13/the-clean-architecture.html)
+- [Domain-Driven Design by Eric Evans](https://www.domainlanguage.com/ddd/)
+- [Repository Pattern - Martin Fowler](https://martinfowler.com/eaaCatalog/repository.html)
+- [SOLID Principles](https://en.wikipedia.org/wiki/SOLID)

packages/guardian/examples/repository-pattern/bad-concrete-repository-in-use-case.ts

@@ -0,0 +1,67 @@
+/**
+ * ❌ BAD EXAMPLE: Concrete repository in use case
+ *
+ * Use case depends on concrete repository implementation instead of interface.
+ * This violates Dependency Inversion Principle.
+ */
+
+class CreateUser {
+    constructor(private userRepo: PrismaUserRepository) {}
+
+    async execute(data: CreateUserRequest): Promise<UserResponseDto> {
+        const user = User.create(data.email, data.name)
+        await this.userRepo.save(user)
+        return UserMapper.toDto(user)
+    }
+}
+
+class PrismaUserRepository {
+    constructor(private prisma: any) {}
+
+    async save(user: User): Promise<void> {
+        await this.prisma.user.create({
+            data: {
+                email: user.getEmail(),
+                name: user.getName(),
+            },
+        })
+    }
+}
+
+class User {
+    static create(email: string, name: string): User {
+        return new User(email, name)
+    }
+
+    constructor(
+        private email: string,
+        private name: string,
+    ) {}
+
+    getEmail(): string {
+        return this.email
+    }
+
+    getName(): string {
+        return this.name
+    }
+}
+
+interface CreateUserRequest {
+    email: string
+    name: string
+}
+
+interface UserResponseDto {
+    email: string
+    name: string
+}
+
+class UserMapper {
+    static toDto(user: User): UserResponseDto {
+        return {
+            email: user.getEmail(),
+            name: user.getName(),
+        }
+    }
+}

packages/guardian/examples/repository-pattern/bad-new-repository.ts

@@ -0,0 +1,69 @@
+/**
+ * ❌ BAD EXAMPLE: Creating repository with 'new' in use case
+ *
+ * Use case creates repository instances directly.
+ * This violates Dependency Injection principle and makes testing difficult.
+ */
+
+class CreateUser {
+    async execute(data: CreateUserRequest): Promise<UserResponseDto> {
+        const userRepo = new UserRepository()
+        const emailService = new EmailService()
+
+        const user = User.create(data.email, data.name)
+        await userRepo.save(user)
+        await emailService.sendWelcomeEmail(user.getEmail())
+
+        return UserMapper.toDto(user)
+    }
+}
+
+class UserRepository {
+    async save(user: User): Promise<void> {
+        console.warn("Saving user to database")
+    }
+}
+
+class EmailService {
+    async sendWelcomeEmail(email: string): Promise<void> {
+        console.warn(`Sending welcome email to ${email}`)
+    }
+}
+
+class User {
+    static create(email: string, name: string): User {
+        return new User(email, name)
+    }
+
+    constructor(
+        private email: string,
+        private name: string,
+    ) {}
+
+    getEmail(): string {
+        return this.email
+    }
+
+    getName(): string {
+        return this.name
+    }
+}
+
+interface CreateUserRequest {
+    email: string
+    name: string
+}
+
+interface UserResponseDto {
+    email: string
+    name: string
+}
+
+class UserMapper {
+    static toDto(user: User): UserResponseDto {
+        return {
+            email: user.getEmail(),
+            name: user.getName(),
+        }
+    }
+}

packages/guardian/examples/repository-pattern/bad-orm-types-in-interface.ts

@@ -0,0 +1,26 @@
+/**
+ * ❌ BAD EXAMPLE: ORM-specific types in repository interface
+ *
+ * This violates Repository Pattern by coupling domain layer to infrastructure (ORM).
+ * Domain should remain persistence-agnostic.
+ */
+
+import { Prisma, PrismaClient } from "@prisma/client"
+
+interface IUserRepository {
+    findOne(query: Prisma.UserWhereInput): Promise<User | null>
+
+    findMany(query: Prisma.UserFindManyArgs): Promise<User[]>
+
+    create(data: Prisma.UserCreateInput): Promise<User>
+
+    update(id: string, data: Prisma.UserUpdateInput): Promise<User>
+}
+
+class User {
+    constructor(
+        public id: string,
+        public email: string,
+        public name: string,
+    ) {}
+}

packages/guardian/examples/repository-pattern/bad-technical-method-names.ts

@@ -0,0 +1,32 @@
+/**
+ * ❌ BAD EXAMPLE: Technical method names
+ *
+ * Repository interface uses database/ORM terminology instead of domain language.
+ * Methods should reflect business operations, not technical implementation.
+ */
+
+interface IUserRepository {
+    findOne(id: string): Promise<User | null>
+
+    findMany(filter: any): Promise<User[]>
+
+    insert(user: User): Promise<void>
+
+    updateOne(id: string, data: any): Promise<void>
+
+    deleteOne(id: string): Promise<void>
+
+    query(sql: string): Promise<any>
+
+    execute(command: string): Promise<void>
+
+    select(fields: string[]): Promise<User[]>
+}
+
+class User {
+    constructor(
+        public id: string,
+        public email: string,
+        public name: string,
+    ) {}
+}

packages/guardian/examples/repository-pattern/good-clean-interface.ts

@@ -0,0 +1,61 @@
+/**
+ * ✅ GOOD EXAMPLE: Clean repository interface
+ *
+ * Repository interface uses only domain types, keeping it persistence-agnostic.
+ * ORM implementation details stay in infrastructure layer.
+ */
+
+interface IUserRepository {
+    findById(id: UserId): Promise<User | null>
+
+    findByEmail(email: Email): Promise<User | null>
+
+    save(user: User): Promise<void>
+
+    delete(id: UserId): Promise<void>
+
+    findAll(criteria: UserSearchCriteria): Promise<User[]>
+}
+
+class UserId {
+    constructor(private readonly value: string) {}
+
+    getValue(): string {
+        return this.value
+    }
+}
+
+class Email {
+    constructor(private readonly value: string) {}
+
+    getValue(): string {
+        return this.value
+    }
+}
+
+class UserSearchCriteria {
+    constructor(
+        public readonly isActive?: boolean,
+        public readonly registeredAfter?: Date,
+    ) {}
+}
+
+class User {
+    constructor(
+        private readonly id: UserId,
+        private email: Email,
+        private name: string,
+    ) {}
+
+    getId(): UserId {
+        return this.id
+    }
+
+    getEmail(): Email {
+        return this.email
+    }
+
+    getName(): string {
+        return this.name
+    }
+}

packages/guardian/examples/repository-pattern/good-dependency-injection.ts

@@ -0,0 +1,98 @@
+/**
+ * ✅ GOOD EXAMPLE: Dependency Injection
+ *
+ * Use case receives dependencies through constructor.
+ * This makes code testable and follows SOLID principles.
+ */
+
+class CreateUser {
+    constructor(
+        private readonly userRepo: IUserRepository,
+        private readonly emailService: IEmailService,
+    ) {}
+
+    async execute(data: CreateUserRequest): Promise<UserResponseDto> {
+        const user = User.create(Email.from(data.email), data.name)
+        await this.userRepo.save(user)
+        await this.emailService.sendWelcomeEmail(user.getEmail())
+        return UserMapper.toDto(user)
+    }
+}
+
+interface IUserRepository {
+    save(user: User): Promise<void>
+    findByEmail(email: Email): Promise<User | null>
+}
+
+interface IEmailService {
+    sendWelcomeEmail(email: Email): Promise<void>
+}
+
+class Email {
+    private constructor(private readonly value: string) {}
+
+    static from(value: string): Email {
+        if (!value.includes("@")) {
+            throw new Error("Invalid email")
+        }
+        return new Email(value)
+    }
+
+    getValue(): string {
+        return this.value
+    }
+}
+
+class User {
+    static create(email: Email, name: string): User {
+        return new User(email, name)
+    }
+
+    private constructor(
+        private readonly email: Email,
+        private readonly name: string,
+    ) {}
+
+    getEmail(): Email {
+        return this.email
+    }
+
+    getName(): string {
+        return this.name
+    }
+}
+
+interface CreateUserRequest {
+    email: string
+    name: string
+}
+
+interface UserResponseDto {
+    email: string
+    name: string
+}
+
+class UserMapper {
+    static toDto(user: User): UserResponseDto {
+        return {
+            email: user.getEmail().getValue(),
+            name: user.getName(),
+        }
+    }
+}
+
+class UserRepository implements IUserRepository {
+    async save(_user: User): Promise<void> {
+        console.warn("Saving user to database")
+    }
+
+    async findByEmail(_email: Email): Promise<User | null> {
+        return null
+    }
+}
+
+class EmailService implements IEmailService {
+    async sendWelcomeEmail(email: Email): Promise<void> {
+        console.warn(`Sending welcome email to ${email.getValue()}`)
+    }
+}

packages/guardian/examples/repository-pattern/good-domain-language.ts

@@ -0,0 +1,81 @@
+/**
+ * ✅ GOOD EXAMPLE: Domain language in repository
+ *
+ * Repository interface uses domain-driven method names that reflect business operations.
+ * Method names are self-documenting and align with ubiquitous language.
+ */
+
+interface IUserRepository {
+    findById(id: UserId): Promise<User | null>
+
+    findByEmail(email: Email): Promise<User | null>
+
+    findActiveUsers(): Promise<User[]>
+
+    save(user: User): Promise<void>
+
+    delete(id: UserId): Promise<void>
+
+    search(criteria: UserSearchCriteria): Promise<User[]>
+
+    countActiveUsers(): Promise<number>
+
+    existsByEmail(email: Email): Promise<boolean>
+}
+
+class UserId {
+    constructor(private readonly value: string) {}
+
+    getValue(): string {
+        return this.value
+    }
+}
+
+class Email {
+    constructor(private readonly value: string) {}
+
+    getValue(): string {
+        return this.value
+    }
+}
+
+class UserSearchCriteria {
+    constructor(
+        public readonly isActive?: boolean,
+        public readonly registeredAfter?: Date,
+        public readonly department?: string,
+    ) {}
+}
+
+class User {
+    constructor(
+        private readonly id: UserId,
+        private email: Email,
+        private name: string,
+        private isActive: boolean,
+    ) {}
+
+    getId(): UserId {
+        return this.id
+    }
+
+    getEmail(): Email {
+        return this.email
+    }
+
+    getName(): string {
+        return this.name
+    }
+
+    isUserActive(): boolean {
+        return this.isActive
+    }
+
+    activate(): void {
+        this.isActive = true
+    }
+
+    deactivate(): void {
+        this.isActive = false
+    }
+}

packages/guardian/examples/repository-pattern/good-interface-in-use-case.ts

@@ -0,0 +1,74 @@
+/**
+ * ✅ GOOD EXAMPLE: Repository interface in use case
+ *
+ * Use case depends on repository interface, not concrete implementation.
+ * This follows Dependency Inversion Principle.
+ */
+
+class CreateUser {
+    constructor(private readonly userRepo: IUserRepository) {}
+
+    async execute(data: CreateUserRequest): Promise<UserResponseDto> {
+        const user = User.create(Email.from(data.email), data.name)
+        await this.userRepo.save(user)
+        return UserMapper.toDto(user)
+    }
+}
+
+interface IUserRepository {
+    save(user: User): Promise<void>
+    findByEmail(email: Email): Promise<User | null>
+}
+
+class Email {
+    private constructor(private readonly value: string) {}
+
+    static from(value: string): Email {
+        if (!value.includes("@")) {
+            throw new Error("Invalid email")
+        }
+        return new Email(value)
+    }
+
+    getValue(): string {
+        return this.value
+    }
+}
+
+class User {
+    static create(email: Email, name: string): User {
+        return new User(email, name)
+    }
+
+    private constructor(
+        private readonly email: Email,
+        private readonly name: string,
+    ) {}
+
+    getEmail(): Email {
+        return this.email
+    }
+
+    getName(): string {
+        return this.name
+    }
+}
+
+interface CreateUserRequest {
+    email: string
+    name: string
+}
+
+interface UserResponseDto {
+    email: string
+    name: string
+}
+
+class UserMapper {
+    static toDto(user: User): UserResponseDto {
+        return {
+            email: user.getEmail().getValue(),
+            name: user.getName(),
+        }
+    }
+}

packages/guardian/package.json

@@ -1,6 +1,6 @@
 {
     "name": "@samiyev/guardian",
-    "version": "0.2.0",
+    "version": "0.5.0",
     "description": "Code quality guardian for vibe coders and enterprise teams - catch hardcodes, architecture violations, and circular deps. Enforce Clean Architecture at scale. Works with Claude, GPT, Copilot.",
     "keywords": [
         "puaros",

packages/guardian/src/api.ts

@@ -8,11 +8,17 @@ import { ICodeParser } from "./domain/services/ICodeParser"
 import { IHardcodeDetector } from "./domain/services/IHardcodeDetector"
 import { INamingConventionDetector } from "./domain/services/INamingConventionDetector"
 import { IFrameworkLeakDetector } from "./domain/services/IFrameworkLeakDetector"
+import { IEntityExposureDetector } from "./domain/services/IEntityExposureDetector"
+import { IDependencyDirectionDetector } from "./domain/services/IDependencyDirectionDetector"
+import { IRepositoryPatternDetector } from "./domain/services/RepositoryPatternDetectorService"
 import { FileScanner } from "./infrastructure/scanners/FileScanner"
 import { CodeParser } from "./infrastructure/parsers/CodeParser"
 import { HardcodeDetector } from "./infrastructure/analyzers/HardcodeDetector"
 import { NamingConventionDetector } from "./infrastructure/analyzers/NamingConventionDetector"
 import { FrameworkLeakDetector } from "./infrastructure/analyzers/FrameworkLeakDetector"
+import { EntityExposureDetector } from "./infrastructure/analyzers/EntityExposureDetector"
+import { DependencyDirectionDetector } from "./infrastructure/analyzers/DependencyDirectionDetector"
+import { RepositoryPatternDetector } from "./infrastructure/analyzers/RepositoryPatternDetector"
 import { ERROR_MESSAGES } from "./shared/constants"
 
 /**
@@ -66,12 +72,19 @@ export async function analyzeProject(
     const hardcodeDetector: IHardcodeDetector = new HardcodeDetector()
     const namingConventionDetector: INamingConventionDetector = new NamingConventionDetector()
     const frameworkLeakDetector: IFrameworkLeakDetector = new FrameworkLeakDetector()
+    const entityExposureDetector: IEntityExposureDetector = new EntityExposureDetector()
+    const dependencyDirectionDetector: IDependencyDirectionDetector =
+        new DependencyDirectionDetector()
+    const repositoryPatternDetector: IRepositoryPatternDetector = new RepositoryPatternDetector()
     const useCase = new AnalyzeProject(
         fileScanner,
         codeParser,
         hardcodeDetector,
         namingConventionDetector,
         frameworkLeakDetector,
+        entityExposureDetector,
+        dependencyDirectionDetector,
+        repositoryPatternDetector,
     )
 
     const result = await useCase.execute(options)
@@ -91,5 +104,8 @@ export type {
     CircularDependencyViolation,
     NamingConventionViolation,
     FrameworkLeakViolation,
+    EntityExposureViolation,
+    DependencyDirectionViolation,
+    RepositoryPatternViolation,
     ProjectMetrics,
 } from "./application/use-cases/AnalyzeProject"

packages/guardian/src/application/use-cases/AnalyzeProject.ts

@@ -5,6 +5,9 @@ import { ICodeParser } from "../../domain/services/ICodeParser"
 import { IHardcodeDetector } from "../../domain/services/IHardcodeDetector"
 import { INamingConventionDetector } from "../../domain/services/INamingConventionDetector"
 import { IFrameworkLeakDetector } from "../../domain/services/IFrameworkLeakDetector"
+import { IEntityExposureDetector } from "../../domain/services/IEntityExposureDetector"
+import { IDependencyDirectionDetector } from "../../domain/services/IDependencyDirectionDetector"
+import { IRepositoryPatternDetector } from "../../domain/services/RepositoryPatternDetectorService"
 import { SourceFile } from "../../domain/entities/SourceFile"
 import { DependencyGraph } from "../../domain/entities/DependencyGraph"
 import { ProjectPath } from "../../domain/value-objects/ProjectPath"
@@ -14,6 +17,7 @@ import {
     LAYERS,
     NAMING_VIOLATION_TYPES,
     REGEX_PATTERNS,
+    REPOSITORY_VIOLATION_TYPES,
     RULES,
     SEVERITY_LEVELS,
 } from "../../shared/constants"
@@ -32,6 +36,9 @@ export interface AnalyzeProjectResponse {
     circularDependencyViolations: CircularDependencyViolation[]
     namingViolations: NamingConventionViolation[]
     frameworkLeakViolations: FrameworkLeakViolation[]
+    entityExposureViolations: EntityExposureViolation[]
+    dependencyDirectionViolations: DependencyDirectionViolation[]
+    repositoryPatternViolations: RepositoryPatternViolation[]
     metrics: ProjectMetrics
 }
 
@@ -95,6 +102,44 @@ export interface FrameworkLeakViolation {
     suggestion: string
 }
 
+export interface EntityExposureViolation {
+    rule: typeof RULES.ENTITY_EXPOSURE
+    entityName: string
+    returnType: string
+    file: string
+    layer: string
+    line?: number
+    methodName?: string
+    message: string
+    suggestion: string
+}
+
+export interface DependencyDirectionViolation {
+    rule: typeof RULES.DEPENDENCY_DIRECTION
+    fromLayer: string
+    toLayer: string
+    importPath: string
+    file: string
+    line?: number
+    message: string
+    suggestion: string
+}
+
+export interface RepositoryPatternViolation {
+    rule: typeof RULES.REPOSITORY_PATTERN
+    violationType:
+        | typeof REPOSITORY_VIOLATION_TYPES.ORM_TYPE_IN_INTERFACE
+        | typeof REPOSITORY_VIOLATION_TYPES.CONCRETE_REPOSITORY_IN_USE_CASE
+        | typeof REPOSITORY_VIOLATION_TYPES.NEW_REPOSITORY_IN_USE_CASE
+        | typeof REPOSITORY_VIOLATION_TYPES.NON_DOMAIN_METHOD_NAME
+    file: string
+    layer: string
+    line?: number
+    details: string
+    message: string
+    suggestion: string
+}
+
 export interface ProjectMetrics {
     totalFiles: number
     totalFunctions: number
@@ -115,6 +160,9 @@ export class AnalyzeProject extends UseCase<
         private readonly hardcodeDetector: IHardcodeDetector,
         private readonly namingConventionDetector: INamingConventionDetector,
         private readonly frameworkLeakDetector: IFrameworkLeakDetector,
+        private readonly entityExposureDetector: IEntityExposureDetector,
+        private readonly dependencyDirectionDetector: IDependencyDirectionDetector,
+        private readonly repositoryPatternDetector: IRepositoryPatternDetector,
     ) {
         super()
     }
@@ -164,6 +212,9 @@ export class AnalyzeProject extends UseCase<
             const circularDependencyViolations = this.detectCircularDependencies(dependencyGraph)
             const namingViolations = this.detectNamingConventions(sourceFiles)
             const frameworkLeakViolations = this.detectFrameworkLeaks(sourceFiles)
+            const entityExposureViolations = this.detectEntityExposures(sourceFiles)
+            const dependencyDirectionViolations = this.detectDependencyDirections(sourceFiles)
+            const repositoryPatternViolations = this.detectRepositoryPatternViolations(sourceFiles)
             const metrics = this.calculateMetrics(sourceFiles, totalFunctions, dependencyGraph)
 
             return ResponseDto.ok({
@@ -174,6 +225,9 @@ export class AnalyzeProject extends UseCase<
                 circularDependencyViolations,
                 namingViolations,
                 frameworkLeakViolations,
+                entityExposureViolations,
+                dependencyDirectionViolations,
+                repositoryPatternViolations,
                 metrics,
             })
         } catch (error) {
@@ -364,6 +418,94 @@ export class AnalyzeProject extends UseCase<
         return violations
     }
 
+    private detectEntityExposures(sourceFiles: SourceFile[]): EntityExposureViolation[] {
+        const violations: EntityExposureViolation[] = []
+
+        for (const file of sourceFiles) {
+            const exposures = this.entityExposureDetector.detectExposures(
+                file.content,
+                file.path.relative,
+                file.layer,
+            )
+
+            for (const exposure of exposures) {
+                violations.push({
+                    rule: RULES.ENTITY_EXPOSURE,
+                    entityName: exposure.entityName,
+                    returnType: exposure.returnType,
+                    file: file.path.relative,
+                    layer: exposure.layer,
+                    line: exposure.line,
+                    methodName: exposure.methodName,
+                    message: exposure.getMessage(),
+                    suggestion: exposure.getSuggestion(),
+                })
+            }
+        }
+
+        return violations
+    }
+
+    private detectDependencyDirections(sourceFiles: SourceFile[]): DependencyDirectionViolation[] {
+        const violations: DependencyDirectionViolation[] = []
+
+        for (const file of sourceFiles) {
+            const directionViolations = this.dependencyDirectionDetector.detectViolations(
+                file.content,
+                file.path.relative,
+                file.layer,
+            )
+
+            for (const violation of directionViolations) {
+                violations.push({
+                    rule: RULES.DEPENDENCY_DIRECTION,
+                    fromLayer: violation.fromLayer,
+                    toLayer: violation.toLayer,
+                    importPath: violation.importPath,
+                    file: file.path.relative,
+                    line: violation.line,
+                    message: violation.getMessage(),
+                    suggestion: violation.getSuggestion(),
+                })
+            }
+        }
+
+        return violations
+    }
+
+    private detectRepositoryPatternViolations(
+        sourceFiles: SourceFile[],
+    ): RepositoryPatternViolation[] {
+        const violations: RepositoryPatternViolation[] = []
+
+        for (const file of sourceFiles) {
+            const patternViolations = this.repositoryPatternDetector.detectViolations(
+                file.content,
+                file.path.relative,
+                file.layer,
+            )
+
+            for (const violation of patternViolations) {
+                violations.push({
+                    rule: RULES.REPOSITORY_PATTERN,
+                    violationType: violation.violationType as
+                        | typeof REPOSITORY_VIOLATION_TYPES.ORM_TYPE_IN_INTERFACE
+                        | typeof REPOSITORY_VIOLATION_TYPES.CONCRETE_REPOSITORY_IN_USE_CASE
+                        | typeof REPOSITORY_VIOLATION_TYPES.NEW_REPOSITORY_IN_USE_CASE
+                        | typeof REPOSITORY_VIOLATION_TYPES.NON_DOMAIN_METHOD_NAME,
+                    file: file.path.relative,
+                    layer: violation.layer,
+                    line: violation.line,
+                    details: violation.details,
+                    message: violation.getMessage(),
+                    suggestion: violation.getSuggestion(),
+                })
+            }
+        }
+
+        return violations
+    }
+
     private calculateMetrics(
         sourceFiles: SourceFile[],
         totalFunctions: number,

packages/guardian/src/cli/constants.ts

@@ -33,7 +33,20 @@ export const CLI_ARGUMENTS = {
     PATH: "<path>",
 } as const
 
-export const DEFAULT_EXCLUDES = ["node_modules", "dist", "build", "coverage"] as const
+export const DEFAULT_EXCLUDES = [
+    "node_modules",
+    "dist",
+    "build",
+    "coverage",
+    "tests",
+    "test",
+    "__tests__",
+    "examples",
+    "**/*.test.ts",
+    "**/*.test.js",
+    "**/*.spec.ts",
+    "**/*.spec.js",
+] as const
 
 export const CLI_MESSAGES = {
     ANALYZING: "\n🛡️  Guardian - Analyzing your code...\n",

packages/guardian/src/cli/index.ts

@@ -39,6 +39,7 @@ program
                 circularDependencyViolations,
                 namingViolations,
                 frameworkLeakViolations,
+                entityExposureViolations,
                 metrics,
             } = result
 
@@ -126,6 +127,33 @@ program
                 })
             }
 
+            // Entity exposure violations
+            if (options.architecture && entityExposureViolations.length > 0) {
+                console.log(
+                    `\n🎭 Found ${String(entityExposureViolations.length)} entity exposure(s):\n`,
+                )
+
+                entityExposureViolations.forEach((ee, index) => {
+                    const location = ee.line ? `${ee.file}:${String(ee.line)}` : ee.file
+                    console.log(`${String(index + 1)}. ${location}`)
+                    console.log(`   Entity: ${ee.entityName}`)
+                    console.log(`   Return Type: ${ee.returnType}`)
+                    if (ee.methodName) {
+                        console.log(`   Method: ${ee.methodName}`)
+                    }
+                    console.log(`   Layer: ${ee.layer}`)
+                    console.log(`   Rule: ${ee.rule}`)
+                    console.log(`   ${ee.message}`)
+                    console.log("   💡 Suggestion:")
+                    ee.suggestion.split("\n").forEach((line) => {
+                        if (line.trim()) {
+                            console.log(`      ${line}`)
+                        }
+                    })
+                    console.log("")
+                })
+            }
+
             // Hardcode violations
             if (options.hardcode && hardcodeViolations.length > 0) {
                 console.log(
@@ -151,7 +179,8 @@ program
                 hardcodeViolations.length +
                 circularDependencyViolations.length +
                 namingViolations.length +
-                frameworkLeakViolations.length
+                frameworkLeakViolations.length +
+                entityExposureViolations.length
 
             if (totalIssues === 0) {
                 console.log(CLI_MESSAGES.NO_ISSUES)

packages/guardian/src/domain/index.ts

@@ -5,9 +5,11 @@ export * from "./value-objects/ValueObject"
 export * from "./value-objects/ProjectPath"
 export * from "./value-objects/HardcodedValue"
 export * from "./value-objects/NamingViolation"
+export * from "./value-objects/RepositoryViolation"
 export * from "./repositories/IBaseRepository"
 export * from "./services/IFileScanner"
 export * from "./services/ICodeParser"
 export * from "./services/IHardcodeDetector"
 export * from "./services/INamingConventionDetector"
+export * from "./services/RepositoryPatternDetectorService"
 export * from "./events/DomainEvent"

packages/guardian/src/domain/services/IDependencyDirectionDetector.ts

@@ -0,0 +1,47 @@
+import { DependencyViolation } from "../value-objects/DependencyViolation"
+
+/**
+ * Interface for detecting dependency direction violations in the codebase
+ *
+ * Dependency direction violations occur when a layer imports from a layer
+ * that it should not depend on according to Clean Architecture principles:
+ * - Domain should not import from Application or Infrastructure
+ * - Application should not import from Infrastructure
+ * - Infrastructure can import from Application and Domain
+ * - Shared can be imported by all layers
+ */
+export interface IDependencyDirectionDetector {
+    /**
+     * Detects dependency direction violations in the given code
+     *
+     * Analyzes import statements to identify violations of dependency rules
+     * between architectural layers.
+     *
+     * @param code - Source code to analyze
+     * @param filePath - Path to the file being analyzed
+     * @param layer - The architectural layer of the file (domain, application, infrastructure, shared)
+     * @returns Array of detected dependency direction violations
+     */
+    detectViolations(
+        code: string,
+        filePath: string,
+        layer: string | undefined,
+    ): DependencyViolation[]
+
+    /**
+     * Checks if an import violates dependency direction rules
+     *
+     * @param fromLayer - The layer that is importing
+     * @param toLayer - The layer being imported
+     * @returns True if the import violates dependency rules
+     */
+    isViolation(fromLayer: string, toLayer: string): boolean
+
+    /**
+     * Extracts the layer from an import path
+     *
+     * @param importPath - The import path to analyze
+     * @returns The layer name if detected, undefined otherwise
+     */
+    extractLayerFromImport(importPath: string): string | undefined
+}

packages/guardian/src/domain/services/IEntityExposureDetector.ts

@@ -0,0 +1,34 @@
+import { EntityExposure } from "../value-objects/EntityExposure"
+
+/**
+ * Interface for detecting entity exposure violations in the codebase
+ *
+ * Entity exposure occurs when domain entities are directly returned from
+ * controllers/routes instead of using DTOs (Data Transfer Objects).
+ * This violates separation of concerns and can expose internal domain logic.
+ */
+export interface IEntityExposureDetector {
+    /**
+     * Detects entity exposure violations in the given code
+     *
+     * Analyzes method return types in controllers/routes to identify
+     * domain entities being directly exposed to external clients.
+     *
+     * @param code - Source code to analyze
+     * @param filePath - Path to the file being analyzed
+     * @param layer - The architectural layer of the file (domain, application, infrastructure, shared)
+     * @returns Array of detected entity exposure violations
+     */
+    detectExposures(code: string, filePath: string, layer: string | undefined): EntityExposure[]
+
+    /**
+     * Checks if a return type is a domain entity
+     *
+     * Domain entities are typically PascalCase nouns without Dto/Request/Response suffixes
+     * and are defined in the domain layer.
+     *
+     * @param returnType - The return type to check
+     * @returns True if the return type appears to be a domain entity
+     */
+    isDomainEntity(returnType: string): boolean
+}

packages/guardian/src/domain/services/RepositoryPatternDetectorService.ts

@@ -0,0 +1,88 @@
+import { RepositoryViolation } from "../value-objects/RepositoryViolation"
+
+/**
+ * Interface for detecting Repository Pattern violations in the codebase
+ *
+ * Repository Pattern violations include:
+ * - ORM-specific types in repository interfaces (domain layer)
+ * - Concrete repository usage in use cases instead of interfaces
+ * - Repository instantiation with 'new' in use cases (should use DI)
+ * - Non-domain method names in repository interfaces
+ *
+ * The Repository Pattern ensures that domain logic remains decoupled from
+ * infrastructure concerns like databases and ORMs.
+ */
+export interface IRepositoryPatternDetector {
+    /**
+     * Detects all Repository Pattern violations in the given code
+     *
+     * Analyzes code for proper implementation of the Repository Pattern,
+     * including interface purity, dependency inversion, and domain language usage.
+     *
+     * @param code - Source code to analyze
+     * @param filePath - Path to the file being analyzed
+     * @param layer - The architectural layer of the file (domain, application, infrastructure, shared)
+     * @returns Array of detected Repository Pattern violations
+     */
+    detectViolations(
+        code: string,
+        filePath: string,
+        layer: string | undefined,
+    ): RepositoryViolation[]
+
+    /**
+     * Checks if a type is an ORM-specific type
+     *
+     * ORM-specific types include Prisma types, TypeORM decorators, Mongoose schemas, etc.
+     * These types should not appear in domain repository interfaces.
+     *
+     * @param typeName - The type name to check
+     * @returns True if the type is ORM-specific
+     */
+    isOrmType(typeName: string): boolean
+
+    /**
+     * Checks if a method name follows domain language conventions
+     *
+     * Domain repository methods should use business-oriented names like:
+     * - findById, findByEmail, findByStatus
+     * - save, create, update
+     * - delete, remove
+     *
+     * Avoid technical database terms like:
+     * - findOne, findMany, query
+     * - insert, select, update (SQL terms)
+     *
+     * @param methodName - The method name to check
+     * @returns True if the method name uses domain language
+     */
+    isDomainMethodName(methodName: string): boolean
+
+    /**
+     * Checks if a file is a repository interface
+     *
+     * Repository interfaces typically:
+     * - Are in the domain layer
+     * - Have names matching I*Repository pattern
+     * - Contain interface definitions
+     *
+     * @param filePath - The file path to check
+     * @param layer - The architectural layer
+     * @returns True if the file is a repository interface
+     */
+    isRepositoryInterface(filePath: string, layer: string | undefined): boolean
+
+    /**
+     * Checks if a file is a use case
+     *
+     * Use cases typically:
+     * - Are in the application layer
+     * - Follow verb-noun naming pattern (CreateUser, UpdateProfile)
+     * - Contain class definitions for business operations
+     *
+     * @param filePath - The file path to check
+     * @param layer - The architectural layer
+     * @returns True if the file is a use case
+     */
+    isUseCase(filePath: string, layer: string | undefined): boolean
+}

packages/guardian/src/domain/value-objects/DependencyViolation.ts

@@ -0,0 +1,162 @@
+import { ValueObject } from "./ValueObject"
+
+interface DependencyViolationProps {
+    readonly fromLayer: string
+    readonly toLayer: string
+    readonly importPath: string
+    readonly filePath: string
+    readonly line?: number
+}
+
+/**
+ * Represents a dependency direction violation in the codebase
+ *
+ * Dependency direction violations occur when a layer imports from a layer
+ * that it should not depend on according to Clean Architecture principles:
+ * - Domain → should not import from Application or Infrastructure
+ * - Application → should not import from Infrastructure
+ * - Infrastructure → can import from Application and Domain (allowed)
+ * - Shared → can be imported by all layers (allowed)
+ *
+ * @example
+ * ```typescript
+ * // Bad: Domain importing from Application
+ * const violation = DependencyViolation.create(
+ *     'domain',
+ *     'application',
+ *     '../../application/dtos/UserDto',
+ *     'src/domain/entities/User.ts',
+ *     5
+ * )
+ *
+ * console.log(violation.getMessage())
+ * // "Domain layer should not import from Application layer"
+ * ```
+ */
+export class DependencyViolation extends ValueObject<DependencyViolationProps> {
+    private constructor(props: DependencyViolationProps) {
+        super(props)
+    }
+
+    public static create(
+        fromLayer: string,
+        toLayer: string,
+        importPath: string,
+        filePath: string,
+        line?: number,
+    ): DependencyViolation {
+        return new DependencyViolation({
+            fromLayer,
+            toLayer,
+            importPath,
+            filePath,
+            line,
+        })
+    }
+
+    public get fromLayer(): string {
+        return this.props.fromLayer
+    }
+
+    public get toLayer(): string {
+        return this.props.toLayer
+    }
+
+    public get importPath(): string {
+        return this.props.importPath
+    }
+
+    public get filePath(): string {
+        return this.props.filePath
+    }
+
+    public get line(): number | undefined {
+        return this.props.line
+    }
+
+    public getMessage(): string {
+        return `${this.capitalizeFirst(this.props.fromLayer)} layer should not import from ${this.capitalizeFirst(this.props.toLayer)} layer`
+    }
+
+    public getSuggestion(): string {
+        const suggestions: string[] = []
+
+        if (this.props.fromLayer === "domain") {
+            suggestions.push(
+                "Domain layer should be independent and not depend on other layers",
+                "Move the imported code to the domain layer if it contains business logic",
+                "Use dependency inversion: define an interface in domain and implement it in infrastructure",
+            )
+        } else if (this.props.fromLayer === "application") {
+            suggestions.push(
+                "Application layer should not depend on infrastructure",
+                "Define an interface (Port) in application layer",
+                "Implement the interface (Adapter) in infrastructure layer",
+                "Use dependency injection to provide the implementation",
+            )
+        }
+
+        return suggestions.join("\n")
+    }
+
+    public getExampleFix(): string {
+        if (this.props.fromLayer === "domain" && this.props.toLayer === "infrastructure") {
+            return `
+// ❌ Bad: Domain depends on Infrastructure (PrismaClient)
+// domain/services/UserService.ts
+class UserService {
+    constructor(private prisma: PrismaClient) {}
+}
+
+// ✅ Good: Domain defines interface, Infrastructure implements
+// domain/repositories/IUserRepository.ts
+interface IUserRepository {
+    findById(id: UserId): Promise<User | null>
+    save(user: User): Promise<void>
+}
+
+// domain/services/UserService.ts
+class UserService {
+    constructor(private userRepo: IUserRepository) {}
+}
+
+// infrastructure/repositories/PrismaUserRepository.ts
+class PrismaUserRepository implements IUserRepository {
+    constructor(private prisma: PrismaClient) {}
+    async findById(id: UserId): Promise<User | null> { }
+    async save(user: User): Promise<void> { }
+}`
+        }
+
+        if (this.props.fromLayer === "application" && this.props.toLayer === "infrastructure") {
+            return `
+// ❌ Bad: Application depends on Infrastructure (SmtpEmailService)
+// application/use-cases/SendEmail.ts
+class SendWelcomeEmail {
+    constructor(private emailService: SmtpEmailService) {}
+}
+
+// ✅ Good: Application defines Port, Infrastructure implements Adapter
+// application/ports/IEmailService.ts
+interface IEmailService {
+    send(to: string, subject: string, body: string): Promise<void>
+}
+
+// application/use-cases/SendEmail.ts
+class SendWelcomeEmail {
+    constructor(private emailService: IEmailService) {}
+}
+
+// infrastructure/adapters/SmtpEmailService.ts
+class SmtpEmailService implements IEmailService {
+    async send(to: string, subject: string, body: string): Promise<void> { }
+}`
+        }
+
+        return ""
+    }
+
+    private capitalizeFirst(str: string): string {
+        return str.charAt(0).toUpperCase() + str.slice(1)
+    }
+}

packages/guardian/src/domain/value-objects/EntityExposure.ts

@@ -0,0 +1,109 @@
+import { ValueObject } from "./ValueObject"
+
+interface EntityExposureProps {
+    readonly entityName: string
+    readonly returnType: string
+    readonly filePath: string
+    readonly layer: string
+    readonly line?: number
+    readonly methodName?: string
+}
+
+/**
+ * Represents an entity exposure violation in the codebase
+ *
+ * Entity exposure occurs when a domain entity is directly exposed in API responses
+ * instead of using DTOs (Data Transfer Objects). This violates the separation of concerns
+ * and can lead to exposing internal domain logic to external clients.
+ *
+ * @example
+ * ```typescript
+ * // Bad: Controller returning domain entity
+ * const exposure = EntityExposure.create(
+ *     'User',
+ *     'User',
+ *     'src/infrastructure/controllers/UserController.ts',
+ *     'infrastructure',
+ *     25,
+ *     'getUser'
+ * )
+ *
+ * console.log(exposure.getMessage())
+ * // "Method 'getUser' returns domain entity 'User' instead of DTO"
+ * ```
+ */
+export class EntityExposure extends ValueObject<EntityExposureProps> {
+    private constructor(props: EntityExposureProps) {
+        super(props)
+    }
+
+    public static create(
+        entityName: string,
+        returnType: string,
+        filePath: string,
+        layer: string,
+        line?: number,
+        methodName?: string,
+    ): EntityExposure {
+        return new EntityExposure({
+            entityName,
+            returnType,
+            filePath,
+            layer,
+            line,
+            methodName,
+        })
+    }
+
+    public get entityName(): string {
+        return this.props.entityName
+    }
+
+    public get returnType(): string {
+        return this.props.returnType
+    }
+
+    public get filePath(): string {
+        return this.props.filePath
+    }
+
+    public get layer(): string {
+        return this.props.layer
+    }
+
+    public get line(): number | undefined {
+        return this.props.line
+    }
+
+    public get methodName(): string | undefined {
+        return this.props.methodName
+    }
+
+    public getMessage(): string {
+        const method = this.props.methodName ? `Method '${this.props.methodName}'` : "Method"
+        return `${method} returns domain entity '${this.props.entityName}' instead of DTO`
+    }
+
+    public getSuggestion(): string {
+        const suggestions = [
+            `Create a DTO class (e.g., ${this.props.entityName}ResponseDto) in the application layer`,
+            `Create a mapper to convert ${this.props.entityName} to ${this.props.entityName}ResponseDto`,
+            `Update the method to return ${this.props.entityName}ResponseDto instead of ${this.props.entityName}`,
+        ]
+        return suggestions.join("\n")
+    }
+
+    public getExampleFix(): string {
+        return `
+// ❌ Bad: Exposing domain entity
+async ${this.props.methodName || "getEntity"}(): Promise<${this.props.entityName}> {
+    return await this.service.find()
+}
+
+// ✅ Good: Using DTO
+async ${this.props.methodName || "getEntity"}(): Promise<${this.props.entityName}ResponseDto> {
+    const entity = await this.service.find()
+    return ${this.props.entityName}Mapper.toDto(entity)
+}`
+    }
+}

packages/guardian/src/domain/value-objects/RepositoryViolation.ts

@@ -0,0 +1,288 @@
+import { ValueObject } from "./ValueObject"
+import { REPOSITORY_VIOLATION_TYPES } from "../../shared/constants/rules"
+import { REPOSITORY_PATTERN_MESSAGES } from "../constants/Messages"
+
+interface RepositoryViolationProps {
+    readonly violationType:
+        | typeof REPOSITORY_VIOLATION_TYPES.ORM_TYPE_IN_INTERFACE
+        | typeof REPOSITORY_VIOLATION_TYPES.CONCRETE_REPOSITORY_IN_USE_CASE
+        | typeof REPOSITORY_VIOLATION_TYPES.NEW_REPOSITORY_IN_USE_CASE
+        | typeof REPOSITORY_VIOLATION_TYPES.NON_DOMAIN_METHOD_NAME
+    readonly filePath: string
+    readonly layer: string
+    readonly line?: number
+    readonly details: string
+    readonly ormType?: string
+    readonly repositoryName?: string
+    readonly methodName?: string
+}
+
+/**
+ * Represents a Repository Pattern violation in the codebase
+ *
+ * Repository Pattern violations occur when:
+ * 1. Repository interfaces contain ORM-specific types
+ * 2. Use cases depend on concrete repository implementations instead of interfaces
+ * 3. Repositories are instantiated with 'new' in use cases
+ * 4. Repository methods use technical names instead of domain language
+ *
+ * @example
+ * ```typescript
+ * // Violation: ORM type in interface
+ * const violation = RepositoryViolation.create(
+ *     'orm-type-in-interface',
+ *     'src/domain/repositories/IUserRepository.ts',
+ *     'domain',
+ *     15,
+ *     'Repository interface uses Prisma-specific type',
+ *     'Prisma.UserWhereInput'
+ * )
+ * ```
+ */
+export class RepositoryViolation extends ValueObject<RepositoryViolationProps> {
+    private constructor(props: RepositoryViolationProps) {
+        super(props)
+    }
+
+    public static create(
+        violationType:
+            | typeof REPOSITORY_VIOLATION_TYPES.ORM_TYPE_IN_INTERFACE
+            | typeof REPOSITORY_VIOLATION_TYPES.CONCRETE_REPOSITORY_IN_USE_CASE
+            | typeof REPOSITORY_VIOLATION_TYPES.NEW_REPOSITORY_IN_USE_CASE
+            | typeof REPOSITORY_VIOLATION_TYPES.NON_DOMAIN_METHOD_NAME,
+        filePath: string,
+        layer: string,
+        line: number | undefined,
+        details: string,
+        ormType?: string,
+        repositoryName?: string,
+        methodName?: string,
+    ): RepositoryViolation {
+        return new RepositoryViolation({
+            violationType,
+            filePath,
+            layer,
+            line,
+            details,
+            ormType,
+            repositoryName,
+            methodName,
+        })
+    }
+
+    public get violationType(): string {
+        return this.props.violationType
+    }
+
+    public get filePath(): string {
+        return this.props.filePath
+    }
+
+    public get layer(): string {
+        return this.props.layer
+    }
+
+    public get line(): number | undefined {
+        return this.props.line
+    }
+
+    public get details(): string {
+        return this.props.details
+    }
+
+    public get ormType(): string | undefined {
+        return this.props.ormType
+    }
+
+    public get repositoryName(): string | undefined {
+        return this.props.repositoryName
+    }
+
+    public get methodName(): string | undefined {
+        return this.props.methodName
+    }
+
+    public getMessage(): string {
+        switch (this.props.violationType) {
+            case REPOSITORY_VIOLATION_TYPES.ORM_TYPE_IN_INTERFACE:
+                return `Repository interface uses ORM-specific type '${this.props.ormType || "unknown"}'. Domain should not depend on infrastructure concerns.`
+
+            case REPOSITORY_VIOLATION_TYPES.CONCRETE_REPOSITORY_IN_USE_CASE:
+                return `Use case depends on concrete repository '${this.props.repositoryName || "unknown"}' instead of interface. Use dependency inversion.`
+
+            case REPOSITORY_VIOLATION_TYPES.NEW_REPOSITORY_IN_USE_CASE:
+                return `Use case creates repository with 'new ${this.props.repositoryName || "Repository"}()'. Use dependency injection instead.`
+
+            case REPOSITORY_VIOLATION_TYPES.NON_DOMAIN_METHOD_NAME:
+                return `Repository method '${this.props.methodName || "unknown"}' uses technical name. Use domain language instead.`
+
+            default:
+                return `Repository pattern violation: ${this.props.details}`
+        }
+    }
+
+    public getSuggestion(): string {
+        switch (this.props.violationType) {
+            case REPOSITORY_VIOLATION_TYPES.ORM_TYPE_IN_INTERFACE:
+                return this.getOrmTypeSuggestion()
+
+            case REPOSITORY_VIOLATION_TYPES.CONCRETE_REPOSITORY_IN_USE_CASE:
+                return this.getConcreteRepositorySuggestion()
+
+            case REPOSITORY_VIOLATION_TYPES.NEW_REPOSITORY_IN_USE_CASE:
+                return this.getNewRepositorySuggestion()
+
+            case REPOSITORY_VIOLATION_TYPES.NON_DOMAIN_METHOD_NAME:
+                return this.getNonDomainMethodSuggestion()
+
+            default:
+                return REPOSITORY_PATTERN_MESSAGES.DEFAULT_SUGGESTION
+        }
+    }
+
+    private getOrmTypeSuggestion(): string {
+        return [
+            REPOSITORY_PATTERN_MESSAGES.STEP_REMOVE_ORM_TYPES,
+            REPOSITORY_PATTERN_MESSAGES.STEP_USE_DOMAIN_TYPES,
+            REPOSITORY_PATTERN_MESSAGES.STEP_KEEP_CLEAN,
+            "",
+            REPOSITORY_PATTERN_MESSAGES.EXAMPLE_PREFIX,
+            REPOSITORY_PATTERN_MESSAGES.BAD_ORM_EXAMPLE,
+            REPOSITORY_PATTERN_MESSAGES.GOOD_DOMAIN_EXAMPLE,
+        ].join("\n")
+    }
+
+    private getConcreteRepositorySuggestion(): string {
+        return [
+            REPOSITORY_PATTERN_MESSAGES.STEP_DEPEND_ON_INTERFACE,
+            REPOSITORY_PATTERN_MESSAGES.STEP_MOVE_TO_INFRASTRUCTURE,
+            REPOSITORY_PATTERN_MESSAGES.STEP_USE_DI,
+            "",
+            REPOSITORY_PATTERN_MESSAGES.EXAMPLE_PREFIX,
+            `❌ Bad: constructor(private repo: ${this.props.repositoryName || "UserRepository"})`,
+            `✅ Good: constructor(private repo: I${this.props.repositoryName?.replace(/^.*?([A-Z]\w+)$/, "$1") || "UserRepository"})`,
+        ].join("\n")
+    }
+
+    private getNewRepositorySuggestion(): string {
+        return [
+            REPOSITORY_PATTERN_MESSAGES.STEP_REMOVE_NEW,
+            REPOSITORY_PATTERN_MESSAGES.STEP_INJECT_CONSTRUCTOR,
+            REPOSITORY_PATTERN_MESSAGES.STEP_CONFIGURE_DI,
+            "",
+            REPOSITORY_PATTERN_MESSAGES.EXAMPLE_PREFIX,
+            REPOSITORY_PATTERN_MESSAGES.BAD_NEW_REPO,
+            REPOSITORY_PATTERN_MESSAGES.GOOD_INJECT_REPO,
+        ].join("\n")
+    }
+
+    private getNonDomainMethodSuggestion(): string {
+        const technicalToDomain = {
+            findOne: REPOSITORY_PATTERN_MESSAGES.SUGGESTION_FINDONE,
+            findMany: REPOSITORY_PATTERN_MESSAGES.SUGGESTION_FINDMANY,
+            insert: REPOSITORY_PATTERN_MESSAGES.SUGGESTION_INSERT,
+            update: REPOSITORY_PATTERN_MESSAGES.SUGGESTION_UPDATE,
+            delete: REPOSITORY_PATTERN_MESSAGES.SUGGESTION_DELETE,
+            query: REPOSITORY_PATTERN_MESSAGES.SUGGESTION_QUERY,
+        }
+
+        const suggestion =
+            technicalToDomain[this.props.methodName as keyof typeof technicalToDomain]
+
+        return [
+            REPOSITORY_PATTERN_MESSAGES.STEP_RENAME_METHOD,
+            REPOSITORY_PATTERN_MESSAGES.STEP_REFLECT_BUSINESS,
+            REPOSITORY_PATTERN_MESSAGES.STEP_AVOID_TECHNICAL,
+            "",
+            REPOSITORY_PATTERN_MESSAGES.EXAMPLE_PREFIX,
+            `❌ Bad: ${this.props.methodName || "findOne"}()`,
+            `✅ Good: ${suggestion || "findById() or findByEmail()"}`,
+        ].join("\n")
+    }
+
+    public getExampleFix(): string {
+        switch (this.props.violationType) {
+            case REPOSITORY_VIOLATION_TYPES.ORM_TYPE_IN_INTERFACE:
+                return this.getOrmTypeExample()
+
+            case REPOSITORY_VIOLATION_TYPES.CONCRETE_REPOSITORY_IN_USE_CASE:
+                return this.getConcreteRepositoryExample()
+
+            case REPOSITORY_VIOLATION_TYPES.NEW_REPOSITORY_IN_USE_CASE:
+                return this.getNewRepositoryExample()
+
+            case REPOSITORY_VIOLATION_TYPES.NON_DOMAIN_METHOD_NAME:
+                return this.getNonDomainMethodExample()
+
+            default:
+                return REPOSITORY_PATTERN_MESSAGES.NO_EXAMPLE
+        }
+    }
+
+    private getOrmTypeExample(): string {
+        return `
+// ❌ BAD: ORM-specific interface
+// domain/repositories/IUserRepository.ts
+interface IUserRepository {
+    findOne(query: { where: { id: string } })  // Prisma-specific
+    create(data: UserCreateInput)  // ORM types in domain
+}
+
+// ✅ GOOD: Clean domain interface
+interface IUserRepository {
+    findById(id: UserId): Promise<User | null>
+    save(user: User): Promise<void>
+    delete(id: UserId): Promise<void>
+}`
+    }
+
+    private getConcreteRepositoryExample(): string {
+        return `
+// ❌ BAD: Use Case with concrete implementation
+class CreateUser {
+    constructor(private prisma: PrismaClient) {}  // VIOLATION!
+}
+
+// ✅ GOOD: Use Case with interface
+class CreateUser {
+    constructor(private userRepo: IUserRepository) {}  // OK
+}`
+    }
+
+    private getNewRepositoryExample(): string {
+        return `
+// ❌ BAD: Creating repository in use case
+class CreateUser {
+    async execute(data: CreateUserRequest) {
+        const repo = new UserRepository()  // VIOLATION!
+        await repo.save(user)
+    }
+}
+
+// ✅ GOOD: Inject repository via constructor
+class CreateUser {
+    constructor(private readonly userRepo: IUserRepository) {}
+
+    async execute(data: CreateUserRequest) {
+        await this.userRepo.save(user)  // OK
+    }
+}`
+    }
+
+    private getNonDomainMethodExample(): string {
+        return `
+// ❌ BAD: Technical method names
+interface IUserRepository {
+    findOne(id: string)  // Database terminology
+    insert(user: User)   // SQL terminology
+    query(filter: any)   // Technical term
+}
+
+// ✅ GOOD: Domain language
+interface IUserRepository {
+    findById(id: UserId): Promise<User | null>
+    save(user: User): Promise<void>
+    findByEmail(email: Email): Promise<User | null>
+}`
+    }
+}

packages/guardian/src/infrastructure/analyzers/DependencyDirectionDetector.ts

@@ -0,0 +1,183 @@
+import { IDependencyDirectionDetector } from "../../domain/services/IDependencyDirectionDetector"
+import { DependencyViolation } from "../../domain/value-objects/DependencyViolation"
+import { LAYERS } from "../../shared/constants/rules"
+
+/**
+ * Detects dependency direction violations between architectural layers
+ *
+ * This detector enforces Clean Architecture dependency rules:
+ * - Domain → should not import from Application or Infrastructure
+ * - Application → should not import from Infrastructure
+ * - Infrastructure → can import from Application and Domain (allowed)
+ * - Shared → can be imported by all layers (allowed)
+ *
+ * @example
+ * ```typescript
+ * const detector = new DependencyDirectionDetector()
+ *
+ * // Detect violations in domain file
+ * const code = `
+ * import { PrismaClient } from '@prisma/client'
+ * import { UserDto } from '../application/dtos/UserDto'
+ * `
+ * const violations = detector.detectViolations(code, 'src/domain/entities/User.ts', 'domain')
+ *
+ * // violations will contain 1 violation for domain importing from application
+ * console.log(violations.length) // 1
+ * console.log(violations[0].getMessage())
+ * // "Domain layer should not import from Application layer"
+ * ```
+ */
+export class DependencyDirectionDetector implements IDependencyDirectionDetector {
+    private readonly dependencyRules: Map<string, Set<string>>
+
+    constructor() {
+        this.dependencyRules = new Map([
+            [LAYERS.DOMAIN, new Set([LAYERS.DOMAIN, LAYERS.SHARED])],
+            [LAYERS.APPLICATION, new Set([LAYERS.DOMAIN, LAYERS.APPLICATION, LAYERS.SHARED])],
+            [
+                LAYERS.INFRASTRUCTURE,
+                new Set([LAYERS.DOMAIN, LAYERS.APPLICATION, LAYERS.INFRASTRUCTURE, LAYERS.SHARED]),
+            ],
+            [
+                LAYERS.SHARED,
+                new Set([LAYERS.DOMAIN, LAYERS.APPLICATION, LAYERS.INFRASTRUCTURE, LAYERS.SHARED]),
+            ],
+        ])
+    }
+
+    /**
+     * Detects dependency direction violations in the given code
+     *
+     * Analyzes import statements to identify violations of dependency rules
+     * between architectural layers.
+     *
+     * @param code - Source code to analyze
+     * @param filePath - Path to the file being analyzed
+     * @param layer - The architectural layer of the file (domain, application, infrastructure, shared)
+     * @returns Array of detected dependency direction violations
+     */
+    public detectViolations(
+        code: string,
+        filePath: string,
+        layer: string | undefined,
+    ): DependencyViolation[] {
+        if (!layer || layer === LAYERS.SHARED) {
+            return []
+        }
+
+        const violations: DependencyViolation[] = []
+        const lines = code.split("\n")
+
+        for (let i = 0; i < lines.length; i++) {
+            const line = lines[i]
+            const lineNumber = i + 1
+
+            const imports = this.extractImports(line)
+            for (const importPath of imports) {
+                const targetLayer = this.extractLayerFromImport(importPath)
+
+                if (targetLayer && this.isViolation(layer, targetLayer)) {
+                    violations.push(
+                        DependencyViolation.create(
+                            layer,
+                            targetLayer,
+                            importPath,
+                            filePath,
+                            lineNumber,
+                        ),
+                    )
+                }
+            }
+        }
+
+        return violations
+    }
+
+    /**
+     * Checks if an import violates dependency direction rules
+     *
+     * @param fromLayer - The layer that is importing
+     * @param toLayer - The layer being imported
+     * @returns True if the import violates dependency rules
+     */
+    public isViolation(fromLayer: string, toLayer: string): boolean {
+        const allowedDependencies = this.dependencyRules.get(fromLayer)
+
+        if (!allowedDependencies) {
+            return false
+        }
+
+        return !allowedDependencies.has(toLayer)
+    }
+
+    /**
+     * Extracts the layer from an import path
+     *
+     * @param importPath - The import path to analyze
+     * @returns The layer name if detected, undefined otherwise
+     */
+    public extractLayerFromImport(importPath: string): string | undefined {
+        const normalizedPath = importPath.replace(/['"]/g, "").toLowerCase()
+
+        const layerPatterns: Array<[string, string]> = [
+            [LAYERS.DOMAIN, "/domain/"],
+            [LAYERS.APPLICATION, "/application/"],
+            [LAYERS.INFRASTRUCTURE, "/infrastructure/"],
+            [LAYERS.SHARED, "/shared/"],
+        ]
+
+        for (const [layer, pattern] of layerPatterns) {
+            if (this.containsLayerPattern(normalizedPath, pattern)) {
+                return layer
+            }
+        }
+
+        return undefined
+    }
+
+    /**
+     * Checks if the normalized path contains the layer pattern
+     */
+    private containsLayerPattern(normalizedPath: string, pattern: string): boolean {
+        return (
+            normalizedPath.includes(pattern) ||
+            normalizedPath.includes(`.${pattern}`) ||
+            normalizedPath.includes(`..${pattern}`) ||
+            normalizedPath.includes(`...${pattern}`)
+        )
+    }
+
+    /**
+     * Extracts import paths from a line of code
+     *
+     * Handles various import statement formats:
+     * - import { X } from 'path'
+     * - import X from 'path'
+     * - import * as X from 'path'
+     * - const X = require('path')
+     *
+     * @param line - A line of code to analyze
+     * @returns Array of import paths found in the line
+     */
+    private extractImports(line: string): string[] {
+        const imports: string[] = []
+
+        const esImportRegex =
+            /import\s+(?:{[^}]*}|[\w*]+(?:\s+as\s+\w+)?|\*\s+as\s+\w+)\s+from\s+['"]([^'"]+)['"]/g
+        let match = esImportRegex.exec(line)
+        while (match) {
+            imports.push(match[1])
+            match = esImportRegex.exec(line)
+        }
+
+        const requireRegex = /require\s*\(\s*['"]([^'"]+)['"]\s*\)/g
+        match = requireRegex.exec(line)
+        while (match) {
+            imports.push(match[1])
+            match = requireRegex.exec(line)
+        }
+
+        return imports
+    }
+}

packages/guardian/src/infrastructure/analyzers/EntityExposureDetector.ts

@@ -0,0 +1,214 @@
+import { IEntityExposureDetector } from "../../domain/services/IEntityExposureDetector"
+import { EntityExposure } from "../../domain/value-objects/EntityExposure"
+import { LAYERS } from "../../shared/constants/rules"
+
+/**
+ * Detects domain entity exposure in controller/route return types
+ *
+ * This detector identifies violations where controllers or route handlers
+ * directly return domain entities instead of using DTOs (Data Transfer Objects).
+ * This violates separation of concerns and can expose internal domain logic.
+ *
+ * @example
+ * ```typescript
+ * const detector = new EntityExposureDetector()
+ *
+ * // Detect exposures in a controller file
+ * const code = `
+ * class UserController {
+ *     async getUser(id: string): Promise<User> {
+ *         return this.userService.findById(id)
+ *     }
+ * }
+ * `
+ * const exposures = detector.detectExposures(code, 'src/infrastructure/controllers/UserController.ts', 'infrastructure')
+ *
+ * // exposures will contain violation for returning User entity
+ * console.log(exposures.length) // 1
+ * console.log(exposures[0].entityName) // 'User'
+ * ```
+ */
+export class EntityExposureDetector implements IEntityExposureDetector {
+    private readonly dtoSuffixes = [
+        "Dto",
+        "DTO",
+        "Request",
+        "Response",
+        "Command",
+        "Query",
+        "Result",
+    ]
+    private readonly controllerPatterns = [
+        /Controller/i,
+        /Route/i,
+        /Handler/i,
+        /Resolver/i,
+        /Gateway/i,
+    ]
+
+    /**
+     * Detects entity exposure violations in the given code
+     *
+     * Analyzes method return types in controllers/routes to identify
+     * domain entities being directly exposed to external clients.
+     *
+     * @param code - Source code to analyze
+     * @param filePath - Path to the file being analyzed
+     * @param layer - The architectural layer of the file (domain, application, infrastructure, shared)
+     * @returns Array of detected entity exposure violations
+     */
+    public detectExposures(
+        code: string,
+        filePath: string,
+        layer: string | undefined,
+    ): EntityExposure[] {
+        if (layer !== LAYERS.INFRASTRUCTURE || !this.isControllerFile(filePath)) {
+            return []
+        }
+
+        const exposures: EntityExposure[] = []
+        const lines = code.split("\n")
+
+        for (let i = 0; i < lines.length; i++) {
+            const line = lines[i]
+            const lineNumber = i + 1
+
+            const methodMatches = this.findMethodReturnTypes(line)
+            for (const match of methodMatches) {
+                const { methodName, returnType } = match
+
+                if (this.isDomainEntity(returnType)) {
+                    exposures.push(
+                        EntityExposure.create(
+                            returnType,
+                            returnType,
+                            filePath,
+                            layer,
+                            lineNumber,
+                            methodName,
+                        ),
+                    )
+                }
+            }
+        }
+
+        return exposures
+    }
+
+    /**
+     * Checks if a return type is a domain entity
+     *
+     * Domain entities are typically PascalCase nouns without Dto/Request/Response suffixes
+     * and are defined in the domain layer.
+     *
+     * @param returnType - The return type to check
+     * @returns True if the return type appears to be a domain entity
+     */
+    public isDomainEntity(returnType: string): boolean {
+        if (!returnType || returnType.trim() === "") {
+            return false
+        }
+
+        const cleanType = this.extractCoreType(returnType)
+
+        if (this.isPrimitiveType(cleanType)) {
+            return false
+        }
+
+        if (this.hasAllowedSuffix(cleanType)) {
+            return false
+        }
+
+        return this.isPascalCase(cleanType)
+    }
+
+    /**
+     * Checks if the file is a controller/route file
+     */
+    private isControllerFile(filePath: string): boolean {
+        return this.controllerPatterns.some((pattern) => pattern.test(filePath))
+    }
+
+    /**
+     * Finds method return types in a line of code
+     */
+    private findMethodReturnTypes(line: string): { methodName: string; returnType: string }[] {
+        const matches: { methodName: string; returnType: string }[] = []
+
+        const methodRegex =
+            /(?:async\s+)?(\w+)\s*\([^)]*\)\s*:\s*Promise<([^>]+)>|(?:async\s+)?(\w+)\s*\([^)]*\)\s*:\s*([A-Z]\w+)/g
+
+        let match
+        while ((match = methodRegex.exec(line)) !== null) {
+            const methodName = match[1] || match[3]
+            const returnType = match[2] || match[4]
+
+            if (methodName && returnType) {
+                matches.push({ methodName, returnType })
+            }
+        }
+
+        return matches
+    }
+
+    /**
+     * Extracts core type from complex type annotations
+     * Examples:
+     * - "Promise<User>" -> "User"
+     * - "User[]" -> "User"
+     * - "User | null" -> "User"
+     */
+    private extractCoreType(returnType: string): string {
+        let cleanType = returnType.trim()
+
+        cleanType = cleanType.replace(/Promise<([^>]+)>/, "$1")
+
+        cleanType = cleanType.replace(/\[\]$/, "")
+
+        if (cleanType.includes("|")) {
+            const types = cleanType.split("|").map((t) => t.trim())
+            const nonNullTypes = types.filter((t) => t !== "null" && t !== "undefined")
+            if (nonNullTypes.length > 0) {
+                cleanType = nonNullTypes[0]
+            }
+        }
+
+        return cleanType.trim()
+    }
+
+    /**
+     * Checks if a type is a primitive type
+     */
+    private isPrimitiveType(type: string): boolean {
+        const primitives = [
+            "string",
+            "number",
+            "boolean",
+            "void",
+            "any",
+            "unknown",
+            "null",
+            "undefined",
+            "object",
+            "never",
+        ]
+        return primitives.includes(type.toLowerCase())
+    }
+
+    /**
+     * Checks if a type has an allowed DTO/Response suffix
+     */
+    private hasAllowedSuffix(type: string): boolean {
+        return this.dtoSuffixes.some((suffix) => type.endsWith(suffix))
+    }
+
+    /**
+     * Checks if a string is in PascalCase
+     */
+    private isPascalCase(str: string): boolean {
+        if (!str || str.length === 0) {
+            return false
+        }
+        return /^[A-Z]([a-z0-9]+[A-Z]?)*[a-z0-9]*$/.test(str) && /[a-z]/.test(str)
+    }
+}

packages/guardian/src/infrastructure/analyzers/RepositoryPatternDetector.ts

@@ -0,0 +1,387 @@
+import { IRepositoryPatternDetector } from "../../domain/services/RepositoryPatternDetectorService"
+import { RepositoryViolation } from "../../domain/value-objects/RepositoryViolation"
+import { LAYERS, REPOSITORY_VIOLATION_TYPES } from "../../shared/constants/rules"
+import { ORM_QUERY_METHODS } from "../constants/orm-methods"
+import { REPOSITORY_PATTERN_MESSAGES } from "../../domain/constants/Messages"
+
+/**
+ * Detects Repository Pattern violations in the codebase
+ *
+ * This detector identifies violations where the Repository Pattern is not properly implemented:
+ * 1. ORM-specific types in repository interfaces (domain should be ORM-agnostic)
+ * 2. Concrete repository usage in use cases (violates dependency inversion)
+ * 3. Repository instantiation with 'new' in use cases (should use DI)
+ * 4. Non-domain method names in repositories (should use ubiquitous language)
+ *
+ * @example
+ * ```typescript
+ * const detector = new RepositoryPatternDetector()
+ *
+ * // Detect violations in a repository interface
+ * const code = `
+ * interface IUserRepository {
+ *     findOne(query: Prisma.UserWhereInput): Promise<User>
+ * }
+ * `
+ * const violations = detector.detectViolations(
+ *     code,
+ *     'src/domain/repositories/IUserRepository.ts',
+ *     'domain'
+ * )
+ *
+ * // violations will contain ORM type violation
+ * console.log(violations.length) // 1
+ * console.log(violations[0].violationType) // 'orm-type-in-interface'
+ * ```
+ */
+export class RepositoryPatternDetector implements IRepositoryPatternDetector {
+    private readonly ormTypePatterns = [
+        /Prisma\./,
+        /PrismaClient/,
+        /TypeORM/,
+        /@Entity/,
+        /@Column/,
+        /@PrimaryColumn/,
+        /@PrimaryGeneratedColumn/,
+        /@ManyToOne/,
+        /@OneToMany/,
+        /@ManyToMany/,
+        /@JoinColumn/,
+        /@JoinTable/,
+        /Mongoose\./,
+        /Schema/,
+        /Model</,
+        /Document/,
+        /Sequelize\./,
+        /DataTypes\./,
+        /FindOptions/,
+        /WhereOptions/,
+        /IncludeOptions/,
+        /QueryInterface/,
+        /MikroORM/,
+        /EntityManager/,
+        /EntityRepository/,
+        /Collection</,
+    ]
+
+    private readonly technicalMethodNames = ORM_QUERY_METHODS
+
+    private readonly domainMethodPatterns = [
+        /^findBy[A-Z]/,
+        /^findAll/,
+        /^save$/,
+        /^create$/,
+        /^update$/,
+        /^delete$/,
+        /^remove$/,
+        /^add$/,
+        /^get[A-Z]/,
+        /^search/,
+        /^list/,
+    ]
+
+    private readonly concreteRepositoryPatterns = [
+        /PrismaUserRepository/,
+        /MongoUserRepository/,
+        /TypeOrmUserRepository/,
+        /SequelizeUserRepository/,
+        /InMemoryUserRepository/,
+        /PostgresUserRepository/,
+        /MySqlUserRepository/,
+        /Repository(?!Interface)/,
+    ]
+
+    /**
+     * Detects all Repository Pattern violations in the given code
+     */
+    public detectViolations(
+        code: string,
+        filePath: string,
+        layer: string | undefined,
+    ): RepositoryViolation[] {
+        const violations: RepositoryViolation[] = []
+
+        if (this.isRepositoryInterface(filePath, layer)) {
+            violations.push(...this.detectOrmTypesInInterface(code, filePath, layer))
+            violations.push(...this.detectNonDomainMethodNames(code, filePath, layer))
+        }
+
+        if (this.isUseCase(filePath, layer)) {
+            violations.push(...this.detectConcreteRepositoryUsage(code, filePath, layer))
+            violations.push(...this.detectNewRepositoryInstantiation(code, filePath, layer))
+        }
+
+        return violations
+    }
+
+    /**
+     * Checks if a type is an ORM-specific type
+     */
+    public isOrmType(typeName: string): boolean {
+        return this.ormTypePatterns.some((pattern) => pattern.test(typeName))
+    }
+
+    /**
+     * Checks if a method name follows domain language conventions
+     */
+    public isDomainMethodName(methodName: string): boolean {
+        if ((this.technicalMethodNames as readonly string[]).includes(methodName)) {
+            return false
+        }
+
+        return this.domainMethodPatterns.some((pattern) => pattern.test(methodName))
+    }
+
+    /**
+     * Checks if a file is a repository interface
+     */
+    public isRepositoryInterface(filePath: string, layer: string | undefined): boolean {
+        if (layer !== LAYERS.DOMAIN) {
+            return false
+        }
+
+        return /I[A-Z]\w*Repository\.ts$/.test(filePath) && /repositories?\//.test(filePath)
+    }
+
+    /**
+     * Checks if a file is a use case
+     */
+    public isUseCase(filePath: string, layer: string | undefined): boolean {
+        if (layer !== LAYERS.APPLICATION) {
+            return false
+        }
+
+        return /use-cases?\//.test(filePath) && /[A-Z][a-z]+[A-Z]\w*\.ts$/.test(filePath)
+    }
+
+    /**
+     * Detects ORM-specific types in repository interfaces
+     */
+    private detectOrmTypesInInterface(
+        code: string,
+        filePath: string,
+        layer: string | undefined,
+    ): RepositoryViolation[] {
+        const violations: RepositoryViolation[] = []
+        const lines = code.split("\n")
+
+        for (let i = 0; i < lines.length; i++) {
+            const line = lines[i]
+            const lineNumber = i + 1
+
+            const methodMatch =
+                /(\w+)\s*\([^)]*:\s*([^)]+)\)\s*:\s*.*?(?:Promise<([^>]+)>|([A-Z]\w+))/.exec(line)
+
+            if (methodMatch) {
+                const params = methodMatch[2]
+                const returnType = methodMatch[3] || methodMatch[4]
+
+                if (this.isOrmType(params)) {
+                    const ormType = this.extractOrmType(params)
+                    violations.push(
+                        RepositoryViolation.create(
+                            REPOSITORY_VIOLATION_TYPES.ORM_TYPE_IN_INTERFACE,
+                            filePath,
+                            layer || LAYERS.DOMAIN,
+                            lineNumber,
+                            `Method parameter uses ORM type: ${ormType}`,
+                            ormType,
+                        ),
+                    )
+                }
+
+                if (returnType && this.isOrmType(returnType)) {
+                    const ormType = this.extractOrmType(returnType)
+                    violations.push(
+                        RepositoryViolation.create(
+                            REPOSITORY_VIOLATION_TYPES.ORM_TYPE_IN_INTERFACE,
+                            filePath,
+                            layer || LAYERS.DOMAIN,
+                            lineNumber,
+                            `Method return type uses ORM type: ${ormType}`,
+                            ormType,
+                        ),
+                    )
+                }
+            }
+
+            for (const pattern of this.ormTypePatterns) {
+                if (pattern.test(line) && !line.trim().startsWith("//")) {
+                    const ormType = this.extractOrmType(line)
+                    violations.push(
+                        RepositoryViolation.create(
+                            REPOSITORY_VIOLATION_TYPES.ORM_TYPE_IN_INTERFACE,
+                            filePath,
+                            layer || LAYERS.DOMAIN,
+                            lineNumber,
+                            `Repository interface contains ORM-specific type: ${ormType}`,
+                            ormType,
+                        ),
+                    )
+                    break
+                }
+            }
+        }
+
+        return violations
+    }
+
+    /**
+     * Detects non-domain method names in repository interfaces
+     */
+    private detectNonDomainMethodNames(
+        code: string,
+        filePath: string,
+        layer: string | undefined,
+    ): RepositoryViolation[] {
+        const violations: RepositoryViolation[] = []
+        const lines = code.split("\n")
+
+        for (let i = 0; i < lines.length; i++) {
+            const line = lines[i]
+            const lineNumber = i + 1
+
+            const methodMatch = /^\s*(\w+)\s*\(/.exec(line)
+
+            if (methodMatch) {
+                const methodName = methodMatch[1]
+
+                if (!this.isDomainMethodName(methodName) && !line.trim().startsWith("//")) {
+                    violations.push(
+                        RepositoryViolation.create(
+                            REPOSITORY_VIOLATION_TYPES.NON_DOMAIN_METHOD_NAME,
+                            filePath,
+                            layer || LAYERS.DOMAIN,
+                            lineNumber,
+                            `Method '${methodName}' uses technical name instead of domain language`,
+                            undefined,
+                            undefined,
+                            methodName,
+                        ),
+                    )
+                }
+            }
+        }
+
+        return violations
+    }
+
+    /**
+     * Detects concrete repository usage in use cases
+     */
+    private detectConcreteRepositoryUsage(
+        code: string,
+        filePath: string,
+        layer: string | undefined,
+    ): RepositoryViolation[] {
+        const violations: RepositoryViolation[] = []
+        const lines = code.split("\n")
+
+        for (let i = 0; i < lines.length; i++) {
+            const line = lines[i]
+            const lineNumber = i + 1
+
+            const constructorParamMatch =
+                /constructor\s*\([^)]*(?:private|public|protected)\s+(?:readonly\s+)?(\w+)\s*:\s*([A-Z]\w*Repository)/.exec(
+                    line,
+                )
+
+            if (constructorParamMatch) {
+                const repositoryType = constructorParamMatch[2]
+
+                if (!repositoryType.startsWith("I")) {
+                    violations.push(
+                        RepositoryViolation.create(
+                            REPOSITORY_VIOLATION_TYPES.CONCRETE_REPOSITORY_IN_USE_CASE,
+                            filePath,
+                            layer || LAYERS.APPLICATION,
+                            lineNumber,
+                            `Use case depends on concrete repository '${repositoryType}'`,
+                            undefined,
+                            repositoryType,
+                        ),
+                    )
+                }
+            }
+
+            const fieldMatch =
+                /(?:private|public|protected)\s+(?:readonly\s+)?(\w+)\s*:\s*([A-Z]\w*Repository)/.exec(
+                    line,
+                )
+
+            if (fieldMatch) {
+                const repositoryType = fieldMatch[2]
+
+                if (
+                    !repositoryType.startsWith("I") &&
+                    !line.includes(REPOSITORY_PATTERN_MESSAGES.CONSTRUCTOR)
+                ) {
+                    violations.push(
+                        RepositoryViolation.create(
+                            REPOSITORY_VIOLATION_TYPES.CONCRETE_REPOSITORY_IN_USE_CASE,
+                            filePath,
+                            layer || LAYERS.APPLICATION,
+                            lineNumber,
+                            `Use case field uses concrete repository '${repositoryType}'`,
+                            undefined,
+                            repositoryType,
+                        ),
+                    )
+                }
+            }
+        }
+
+        return violations
+    }
+
+    /**
+     * Detects 'new Repository()' instantiation in use cases
+     */
+    private detectNewRepositoryInstantiation(
+        code: string,
+        filePath: string,
+        layer: string | undefined,
+    ): RepositoryViolation[] {
+        const violations: RepositoryViolation[] = []
+        const lines = code.split("\n")
+
+        for (let i = 0; i < lines.length; i++) {
+            const line = lines[i]
+            const lineNumber = i + 1
+
+            const newRepositoryMatch = /new\s+([A-Z]\w*Repository)\s*\(/.exec(line)
+
+            if (newRepositoryMatch && !line.trim().startsWith("//")) {
+                const repositoryName = newRepositoryMatch[1]
+                violations.push(
+                    RepositoryViolation.create(
+                        REPOSITORY_VIOLATION_TYPES.NEW_REPOSITORY_IN_USE_CASE,
+                        filePath,
+                        layer || LAYERS.APPLICATION,
+                        lineNumber,
+                        `Use case creates repository with 'new ${repositoryName}()'`,
+                        undefined,
+                        repositoryName,
+                    ),
+                )
+            }
+        }
+
+        return violations
+    }
+
+    /**
+     * Extracts ORM type name from a code line
+     */
+    private extractOrmType(line: string): string {
+        for (const pattern of this.ormTypePatterns) {
+            const match = line.match(pattern)
+            if (match) {
+                const startIdx = match.index || 0
+                const typeMatch = /[\w.]+/.exec(line.slice(startIdx))
+                return typeMatch ? typeMatch[0] : REPOSITORY_PATTERN_MESSAGES.UNKNOWN_TYPE
+            }
+        }
+        return REPOSITORY_PATTERN_MESSAGES.UNKNOWN_TYPE
+    }
+}

packages/guardian/src/infrastructure/constants/naming-patterns.ts

@@ -0,0 +1,2 @@
+export const NAMING_SUGGESTION_DEFAULT =
+    "Move to application or infrastructure layer, or rename to follow domain patterns"

packages/guardian/src/infrastructure/constants/orm-methods.ts

@@ -0,0 +1,24 @@
+export const ORM_QUERY_METHODS = [
+    "findOne",
+    "findMany",
+    "findFirst",
+    "findAll",
+    "findAndCountAll",
+    "insert",
+    "insertMany",
+    "insertOne",
+    "updateOne",
+    "updateMany",
+    "deleteOne",
+    "deleteMany",
+    "select",
+    "query",
+    "execute",
+    "run",
+    "exec",
+    "aggregate",
+    "count",
+    "exists",
+] as const
+
+export type OrmQueryMethod = (typeof ORM_QUERY_METHODS)[number]

packages/guardian/src/infrastructure/constants/type-patterns.ts

@@ -0,0 +1,28 @@
+export const DTO_SUFFIXES = [
+    "Dto",
+    "DTO",
+    "Request",
+    "Response",
+    "Command",
+    "Query",
+    "Result",
+] as const
+
+export const PRIMITIVE_TYPES = [
+    "string",
+    "number",
+    "boolean",
+    "void",
+    "any",
+    "unknown",
+    "null",
+    "undefined",
+    "object",
+    "never",
+] as const
+
+export const NULLABLE_TYPES = ["null", "undefined"] as const
+
+export const TEST_FILE_EXTENSIONS = [".test.", ".spec."] as const
+
+export const TEST_FILE_SUFFIXES = [".test.ts", ".test.js", ".spec.ts", ".spec.js"] as const

packages/guardian/src/infrastructure/index.ts

@@ -1,3 +1,4 @@
 export * from "./parsers/CodeParser"
 export * from "./scanners/FileScanner"
 export * from "./analyzers/HardcodeDetector"
+export * from "./analyzers/RepositoryPatternDetector"

packages/guardian/src/shared/constants/rules.ts

@@ -7,6 +7,9 @@ export const RULES = {
     CIRCULAR_DEPENDENCY: "circular-dependency",
     NAMING_CONVENTION: "naming-convention",
     FRAMEWORK_LEAK: "framework-leak",
+    ENTITY_EXPOSURE: "entity-exposure",
+    DEPENDENCY_DIRECTION: "dependency-direction",
+    REPOSITORY_PATTERN: "repository-pattern",
 } as const
 
 /**
@@ -395,4 +398,15 @@ export const FRAMEWORK_LEAK_MESSAGES = {
     DOMAIN_IMPORT:
         'Domain layer imports framework-specific package "{package}". Use interfaces and dependency injection instead.',
     SUGGESTION: "Create an interface in domain layer and implement it in infrastructure layer.",
+    PACKAGE_PLACEHOLDER: "{package}",
+} as const
+
+/**
+ * Repository pattern violation types
+ */
+export const REPOSITORY_VIOLATION_TYPES = {
+    ORM_TYPE_IN_INTERFACE: "orm-type-in-interface",
+    CONCRETE_REPOSITORY_IN_USE_CASE: "concrete-repository-in-use-case",
+    NEW_REPOSITORY_IN_USE_CASE: "new-repository-in-use-case",
+    NON_DOMAIN_METHOD_NAME: "non-domain-method-name",
 } as const

packages/guardian/tests/DependencyDirectionDetector.test.ts

@@ -0,0 +1,511 @@
+import { describe, it, expect } from "vitest"
+import { DependencyDirectionDetector } from "../src/infrastructure/analyzers/DependencyDirectionDetector"
+import { LAYERS } from "../src/shared/constants/rules"
+
+describe("DependencyDirectionDetector", () => {
+    const detector = new DependencyDirectionDetector()
+
+    describe("extractLayerFromImport", () => {
+        it("should extract domain layer from import path", () => {
+            expect(detector.extractLayerFromImport("../domain/entities/User")).toBe(LAYERS.DOMAIN)
+            expect(detector.extractLayerFromImport("../../domain/value-objects/Email")).toBe(
+                LAYERS.DOMAIN,
+            )
+            expect(detector.extractLayerFromImport("../../../domain/services/UserService")).toBe(
+                LAYERS.DOMAIN,
+            )
+        })
+
+        it("should extract application layer from import path", () => {
+            expect(detector.extractLayerFromImport("../application/use-cases/CreateUser")).toBe(
+                LAYERS.APPLICATION,
+            )
+            expect(detector.extractLayerFromImport("../../application/dtos/UserDto")).toBe(
+                LAYERS.APPLICATION,
+            )
+            expect(detector.extractLayerFromImport("../../../application/mappers/UserMapper")).toBe(
+                LAYERS.APPLICATION,
+            )
+        })
+
+        it("should extract infrastructure layer from import path", () => {
+            expect(
+                detector.extractLayerFromImport("../infrastructure/controllers/UserController"),
+            ).toBe(LAYERS.INFRASTRUCTURE)
+            expect(
+                detector.extractLayerFromImport("../../infrastructure/repositories/UserRepository"),
+            ).toBe(LAYERS.INFRASTRUCTURE)
+        })
+
+        it("should extract shared layer from import path", () => {
+            expect(detector.extractLayerFromImport("../shared/types/Result")).toBe(LAYERS.SHARED)
+            expect(detector.extractLayerFromImport("../../shared/constants/rules")).toBe(
+                LAYERS.SHARED,
+            )
+        })
+
+        it("should return undefined for non-layer imports", () => {
+            expect(detector.extractLayerFromImport("express")).toBeUndefined()
+            expect(detector.extractLayerFromImport("../utils/helper")).toBeUndefined()
+            expect(detector.extractLayerFromImport("../../lib/logger")).toBeUndefined()
+        })
+    })
+
+    describe("isViolation", () => {
+        it("should allow domain to import from domain", () => {
+            expect(detector.isViolation(LAYERS.DOMAIN, LAYERS.DOMAIN)).toBe(false)
+        })
+
+        it("should allow domain to import from shared", () => {
+            expect(detector.isViolation(LAYERS.DOMAIN, LAYERS.SHARED)).toBe(false)
+        })
+
+        it("should NOT allow domain to import from application", () => {
+            expect(detector.isViolation(LAYERS.DOMAIN, LAYERS.APPLICATION)).toBe(true)
+        })
+
+        it("should NOT allow domain to import from infrastructure", () => {
+            expect(detector.isViolation(LAYERS.DOMAIN, LAYERS.INFRASTRUCTURE)).toBe(true)
+        })
+
+        it("should allow application to import from domain", () => {
+            expect(detector.isViolation(LAYERS.APPLICATION, LAYERS.DOMAIN)).toBe(false)
+        })
+
+        it("should allow application to import from application", () => {
+            expect(detector.isViolation(LAYERS.APPLICATION, LAYERS.APPLICATION)).toBe(false)
+        })
+
+        it("should allow application to import from shared", () => {
+            expect(detector.isViolation(LAYERS.APPLICATION, LAYERS.SHARED)).toBe(false)
+        })
+
+        it("should NOT allow application to import from infrastructure", () => {
+            expect(detector.isViolation(LAYERS.APPLICATION, LAYERS.INFRASTRUCTURE)).toBe(true)
+        })
+
+        it("should allow infrastructure to import from domain", () => {
+            expect(detector.isViolation(LAYERS.INFRASTRUCTURE, LAYERS.DOMAIN)).toBe(false)
+        })
+
+        it("should allow infrastructure to import from application", () => {
+            expect(detector.isViolation(LAYERS.INFRASTRUCTURE, LAYERS.APPLICATION)).toBe(false)
+        })
+
+        it("should allow infrastructure to import from infrastructure", () => {
+            expect(detector.isViolation(LAYERS.INFRASTRUCTURE, LAYERS.INFRASTRUCTURE)).toBe(false)
+        })
+
+        it("should allow infrastructure to import from shared", () => {
+            expect(detector.isViolation(LAYERS.INFRASTRUCTURE, LAYERS.SHARED)).toBe(false)
+        })
+
+        it("should allow shared to import from any layer", () => {
+            expect(detector.isViolation(LAYERS.SHARED, LAYERS.DOMAIN)).toBe(false)
+            expect(detector.isViolation(LAYERS.SHARED, LAYERS.APPLICATION)).toBe(false)
+            expect(detector.isViolation(LAYERS.SHARED, LAYERS.INFRASTRUCTURE)).toBe(false)
+            expect(detector.isViolation(LAYERS.SHARED, LAYERS.SHARED)).toBe(false)
+        })
+    })
+
+    describe("detectViolations", () => {
+        describe("Domain layer violations", () => {
+            it("should detect domain importing from application", () => {
+                const code = `
+import { UserDto } from '../../application/dtos/UserDto'
+
+export class User {
+    constructor(private id: string) {}
+}`
+                const violations = detector.detectViolations(
+                    code,
+                    "src/domain/entities/User.ts",
+                    LAYERS.DOMAIN,
+                )
+
+                expect(violations).toHaveLength(1)
+                expect(violations[0].fromLayer).toBe(LAYERS.DOMAIN)
+                expect(violations[0].toLayer).toBe(LAYERS.APPLICATION)
+                expect(violations[0].importPath).toBe("../../application/dtos/UserDto")
+                expect(violations[0].line).toBe(2)
+            })
+
+            it("should detect domain importing from infrastructure", () => {
+                const code = `
+import { PrismaClient } from '../../infrastructure/database/PrismaClient'
+
+export class UserRepository {
+    constructor(private prisma: PrismaClient) {}
+}`
+                const violations = detector.detectViolations(
+                    code,
+                    "src/domain/repositories/UserRepository.ts",
+                    LAYERS.DOMAIN,
+                )
+
+                expect(violations).toHaveLength(1)
+                expect(violations[0].fromLayer).toBe(LAYERS.DOMAIN)
+                expect(violations[0].toLayer).toBe(LAYERS.INFRASTRUCTURE)
+                expect(violations[0].importPath).toBe("../../infrastructure/database/PrismaClient")
+            })
+
+            it("should NOT detect domain importing from domain", () => {
+                const code = `
+import { Email } from '../value-objects/Email'
+import { UserId } from '../value-objects/UserId'
+
+export class User {
+    constructor(
+        private id: UserId,
+        private email: Email
+    ) {}
+}`
+                const violations = detector.detectViolations(
+                    code,
+                    "src/domain/entities/User.ts",
+                    LAYERS.DOMAIN,
+                )
+
+                expect(violations).toHaveLength(0)
+            })
+
+            it("should NOT detect domain importing from shared", () => {
+                const code = `
+import { Result } from '../../shared/types/Result'
+
+export class User {
+    static create(id: string): Result<User> {
+        return Result.ok(new User(id))
+    }
+}`
+                const violations = detector.detectViolations(
+                    code,
+                    "src/domain/entities/User.ts",
+                    LAYERS.DOMAIN,
+                )
+
+                expect(violations).toHaveLength(0)
+            })
+        })
+
+        describe("Application layer violations", () => {
+            it("should detect application importing from infrastructure", () => {
+                const code = `
+import { SmtpEmailService } from '../../infrastructure/email/SmtpEmailService'
+
+export class SendWelcomeEmail {
+    constructor(private emailService: SmtpEmailService) {}
+}`
+                const violations = detector.detectViolations(
+                    code,
+                    "src/application/use-cases/SendWelcomeEmail.ts",
+                    LAYERS.APPLICATION,
+                )
+
+                expect(violations).toHaveLength(1)
+                expect(violations[0].fromLayer).toBe(LAYERS.APPLICATION)
+                expect(violations[0].toLayer).toBe(LAYERS.INFRASTRUCTURE)
+                expect(violations[0].getMessage()).toContain(
+                    "Application layer should not import from Infrastructure layer",
+                )
+            })
+
+            it("should NOT detect application importing from domain", () => {
+                const code = `
+import { User } from '../../domain/entities/User'
+import { IUserRepository } from '../../domain/repositories/IUserRepository'
+
+export class CreateUser {
+    constructor(private userRepo: IUserRepository) {}
+}`
+                const violations = detector.detectViolations(
+                    code,
+                    "src/application/use-cases/CreateUser.ts",
+                    LAYERS.APPLICATION,
+                )
+
+                expect(violations).toHaveLength(0)
+            })
+
+            it("should NOT detect application importing from application", () => {
+                const code = `
+import { UserResponseDto } from '../dtos/UserResponseDto'
+import { UserMapper } from '../mappers/UserMapper'
+
+export class GetUser {
+    execute(id: string): UserResponseDto {
+        return UserMapper.toDto(user)
+    }
+}`
+                const violations = detector.detectViolations(
+                    code,
+                    "src/application/use-cases/GetUser.ts",
+                    LAYERS.APPLICATION,
+                )
+
+                expect(violations).toHaveLength(0)
+            })
+
+            it("should NOT detect application importing from shared", () => {
+                const code = `
+import { Result } from '../../shared/types/Result'
+
+export class CreateUser {
+    execute(): Result<User> {
+        return Result.ok(user)
+    }
+}`
+                const violations = detector.detectViolations(
+                    code,
+                    "src/application/use-cases/CreateUser.ts",
+                    LAYERS.APPLICATION,
+                )
+
+                expect(violations).toHaveLength(0)
+            })
+        })
+
+        describe("Infrastructure layer", () => {
+            it("should NOT detect infrastructure importing from domain", () => {
+                const code = `
+import { User } from '../../domain/entities/User'
+import { IUserRepository } from '../../domain/repositories/IUserRepository'
+
+export class PrismaUserRepository implements IUserRepository {
+    async save(user: User): Promise<void> {}
+}`
+                const violations = detector.detectViolations(
+                    code,
+                    "src/infrastructure/repositories/PrismaUserRepository.ts",
+                    LAYERS.INFRASTRUCTURE,
+                )
+
+                expect(violations).toHaveLength(0)
+            })
+
+            it("should NOT detect infrastructure importing from application", () => {
+                const code = `
+import { CreateUser } from '../../application/use-cases/CreateUser'
+import { UserResponseDto } from '../../application/dtos/UserResponseDto'
+
+export class UserController {
+    constructor(private createUser: CreateUser) {}
+}`
+                const violations = detector.detectViolations(
+                    code,
+                    "src/infrastructure/controllers/UserController.ts",
+                    LAYERS.INFRASTRUCTURE,
+                )
+
+                expect(violations).toHaveLength(0)
+            })
+
+            it("should NOT detect infrastructure importing from infrastructure", () => {
+                const code = `
+import { DatabaseConnection } from '../database/DatabaseConnection'
+
+export class PrismaUserRepository {
+    constructor(private db: DatabaseConnection) {}
+}`
+                const violations = detector.detectViolations(
+                    code,
+                    "src/infrastructure/repositories/PrismaUserRepository.ts",
+                    LAYERS.INFRASTRUCTURE,
+                )
+
+                expect(violations).toHaveLength(0)
+            })
+        })
+
+        describe("Multiple violations", () => {
+            it("should detect multiple violations in same file", () => {
+                const code = `
+import { UserDto } from '../../application/dtos/UserDto'
+import { EmailService } from '../../infrastructure/email/EmailService'
+import { Logger } from '../../infrastructure/logging/Logger'
+
+export class User {
+    constructor() {}
+}`
+                const violations = detector.detectViolations(
+                    code,
+                    "src/domain/entities/User.ts",
+                    LAYERS.DOMAIN,
+                )
+
+                expect(violations).toHaveLength(3)
+                expect(violations[0].toLayer).toBe(LAYERS.APPLICATION)
+                expect(violations[1].toLayer).toBe(LAYERS.INFRASTRUCTURE)
+                expect(violations[2].toLayer).toBe(LAYERS.INFRASTRUCTURE)
+            })
+        })
+
+        describe("Import statement formats", () => {
+            it("should detect violations in named imports", () => {
+                const code = `import { UserDto, UserRequest } from '../../application/dtos/UserDto'`
+                const violations = detector.detectViolations(
+                    code,
+                    "src/domain/entities/User.ts",
+                    LAYERS.DOMAIN,
+                )
+
+                expect(violations).toHaveLength(1)
+            })
+
+            it("should detect violations in default imports", () => {
+                const code = `import UserDto from '../../application/dtos/UserDto'`
+                const violations = detector.detectViolations(
+                    code,
+                    "src/domain/entities/User.ts",
+                    LAYERS.DOMAIN,
+                )
+
+                expect(violations).toHaveLength(1)
+            })
+
+            it("should detect violations in namespace imports", () => {
+                const code = `import * as Dtos from '../../application/dtos'`
+                const violations = detector.detectViolations(
+                    code,
+                    "src/domain/entities/User.ts",
+                    LAYERS.DOMAIN,
+                )
+
+                expect(violations).toHaveLength(1)
+            })
+
+            it("should detect violations in require statements", () => {
+                const code = `const UserDto = require('../../application/dtos/UserDto')`
+                const violations = detector.detectViolations(
+                    code,
+                    "src/domain/entities/User.ts",
+                    LAYERS.DOMAIN,
+                )
+
+                expect(violations).toHaveLength(1)
+            })
+        })
+
+        describe("Edge cases", () => {
+            it("should return empty array for shared layer", () => {
+                const code = `
+import { User } from '../../domain/entities/User'
+import { CreateUser } from '../../application/use-cases/CreateUser'
+`
+                const violations = detector.detectViolations(
+                    code,
+                    "src/shared/types/Result.ts",
+                    LAYERS.SHARED,
+                )
+
+                expect(violations).toHaveLength(0)
+            })
+
+            it("should return empty array for undefined layer", () => {
+                const code = `import { UserDto } from '../../application/dtos/UserDto'`
+                const violations = detector.detectViolations(code, "src/utils/helper.ts", undefined)
+
+                expect(violations).toHaveLength(0)
+            })
+
+            it("should handle empty code", () => {
+                const violations = detector.detectViolations(
+                    "",
+                    "src/domain/entities/User.ts",
+                    LAYERS.DOMAIN,
+                )
+
+                expect(violations).toHaveLength(0)
+            })
+        })
+
+        describe("getMessage", () => {
+            it("should return correct message for domain -> application violation", () => {
+                const code = `import { UserDto } from '../../application/dtos/UserDto'`
+                const violations = detector.detectViolations(
+                    code,
+                    "src/domain/entities/User.ts",
+                    LAYERS.DOMAIN,
+                )
+
+                expect(violations[0].getMessage()).toBe(
+                    "Domain layer should not import from Application layer",
+                )
+            })
+
+            it("should return correct message for application -> infrastructure violation", () => {
+                const code = `import { SmtpEmailService } from '../../infrastructure/email/SmtpEmailService'`
+                const violations = detector.detectViolations(
+                    code,
+                    "src/application/use-cases/SendEmail.ts",
+                    LAYERS.APPLICATION,
+                )
+
+                expect(violations[0].getMessage()).toBe(
+                    "Application layer should not import from Infrastructure layer",
+                )
+            })
+        })
+
+        describe("getSuggestion", () => {
+            it("should return suggestions for domain layer violations", () => {
+                const code = `import { PrismaClient } from '../../infrastructure/database'`
+                const violations = detector.detectViolations(
+                    code,
+                    "src/domain/services/UserService.ts",
+                    LAYERS.DOMAIN,
+                )
+
+                const suggestion = violations[0].getSuggestion()
+                expect(suggestion).toContain("Domain layer should be independent")
+                expect(suggestion).toContain("dependency inversion")
+            })
+
+            it("should return suggestions for application layer violations", () => {
+                const code = `import { SmtpEmailService } from '../../infrastructure/email/SmtpEmailService'`
+                const violations = detector.detectViolations(
+                    code,
+                    "src/application/use-cases/SendEmail.ts",
+                    LAYERS.APPLICATION,
+                )
+
+                const suggestion = violations[0].getSuggestion()
+                expect(suggestion).toContain(
+                    "Application layer should not depend on infrastructure",
+                )
+                expect(suggestion).toContain("Port")
+                expect(suggestion).toContain("Adapter")
+            })
+        })
+
+        describe("getExampleFix", () => {
+            it("should return example fix for domain -> infrastructure violation", () => {
+                const code = `import { PrismaClient } from '../../infrastructure/database'`
+                const violations = detector.detectViolations(
+                    code,
+                    "src/domain/services/UserService.ts",
+                    LAYERS.DOMAIN,
+                )
+
+                const example = violations[0].getExampleFix()
+                expect(example).toContain("// ❌ Bad")
+                expect(example).toContain("// ✅ Good")
+                expect(example).toContain("IUserRepository")
+            })
+
+            it("should return example fix for application -> infrastructure violation", () => {
+                const code = `import { SmtpEmailService } from '../../infrastructure/email/SmtpEmailService'`
+                const violations = detector.detectViolations(
+                    code,
+                    "src/application/use-cases/SendEmail.ts",
+                    LAYERS.APPLICATION,
+                )
+
+                const example = violations[0].getExampleFix()
+                expect(example).toContain("// ❌ Bad")
+                expect(example).toContain("// ✅ Good")
+                expect(example).toContain("IEmailService")
+            })
+        })
+    })
+})

packages/guardian/tests/EntityExposureDetector.test.ts

@@ -0,0 +1,362 @@
+import { describe, it, expect, beforeEach } from "vitest"
+import { EntityExposureDetector } from "../src/infrastructure/analyzers/EntityExposureDetector"
+
+describe("EntityExposureDetector", () => {
+    let detector: EntityExposureDetector
+
+    beforeEach(() => {
+        detector = new EntityExposureDetector()
+    })
+
+    describe("detectExposures", () => {
+        it("should detect entity exposure in controller", () => {
+            const code = `
+class UserController {
+    async getUser(id: string): Promise<User> {
+        return this.userService.findById(id)
+    }
+}
+`
+            const exposures = detector.detectExposures(
+                code,
+                "src/infrastructure/controllers/UserController.ts",
+                "infrastructure",
+            )
+
+            expect(exposures).toHaveLength(1)
+            expect(exposures[0].entityName).toBe("User")
+            expect(exposures[0].returnType).toBe("User")
+            expect(exposures[0].methodName).toBe("getUser")
+            expect(exposures[0].layer).toBe("infrastructure")
+        })
+
+        it("should detect multiple entity exposures", () => {
+            const code = `
+class OrderController {
+    async getOrder(id: string): Promise<Order> {
+        return this.orderService.findById(id)
+    }
+
+    async getUser(userId: string): Promise<User> {
+        return this.userService.findById(userId)
+    }
+}
+`
+            const exposures = detector.detectExposures(
+                code,
+                "src/infrastructure/controllers/OrderController.ts",
+                "infrastructure",
+            )
+
+            expect(exposures).toHaveLength(2)
+            expect(exposures[0].entityName).toBe("Order")
+            expect(exposures[1].entityName).toBe("User")
+        })
+
+        it("should not detect DTO return types", () => {
+            const code = `
+class UserController {
+    async getUser(id: string): Promise<UserResponseDto> {
+        const user = await this.userService.findById(id)
+        return UserMapper.toDto(user)
+    }
+}
+`
+            const exposures = detector.detectExposures(
+                code,
+                "src/infrastructure/controllers/UserController.ts",
+                "infrastructure",
+            )
+
+            expect(exposures).toHaveLength(0)
+        })
+
+        it("should not detect primitive return types", () => {
+            const code = `
+class UserController {
+    async getUserCount(): Promise<number> {
+        return this.userService.count()
+    }
+
+    async getUserName(id: string): Promise<string> {
+        return this.userService.getName(id)
+    }
+
+    async deleteUser(id: string): Promise<void> {
+        await this.userService.delete(id)
+    }
+}
+`
+            const exposures = detector.detectExposures(
+                code,
+                "src/infrastructure/controllers/UserController.ts",
+                "infrastructure",
+            )
+
+            expect(exposures).toHaveLength(0)
+        })
+
+        it("should not detect exposures in non-controller files", () => {
+            const code = `
+class UserService {
+    async findById(id: string): Promise<User> {
+        return this.repository.findById(id)
+    }
+}
+`
+            const exposures = detector.detectExposures(
+                code,
+                "src/application/services/UserService.ts",
+                "application",
+            )
+
+            expect(exposures).toHaveLength(0)
+        })
+
+        it("should not detect exposures outside infrastructure layer", () => {
+            const code = `
+class CreateUser {
+    async execute(request: CreateUserRequest): Promise<User> {
+        return User.create(request)
+    }
+}
+`
+            const exposures = detector.detectExposures(
+                code,
+                "src/application/use-cases/CreateUser.ts",
+                "application",
+            )
+
+            expect(exposures).toHaveLength(0)
+        })
+
+        it("should detect exposures in route handlers", () => {
+            const code = `
+class UserRoutes {
+    async getUser(id: string): Promise<User> {
+        return this.service.findById(id)
+    }
+}
+`
+            const exposures = detector.detectExposures(
+                code,
+                "src/infrastructure/routes/UserRoutes.ts",
+                "infrastructure",
+            )
+
+            expect(exposures).toHaveLength(1)
+            expect(exposures[0].entityName).toBe("User")
+        })
+
+        it("should detect exposures with async methods", () => {
+            const code = `
+class UserHandler {
+    async handleGetUser(id: string): Promise<User> {
+        return this.service.findById(id)
+    }
+}
+`
+            const exposures = detector.detectExposures(
+                code,
+                "src/infrastructure/handlers/UserHandler.ts",
+                "infrastructure",
+            )
+
+            expect(exposures).toHaveLength(1)
+        })
+
+        it("should not detect Request/Response suffixes", () => {
+            const code = `
+class UserController {
+    async createUser(request: CreateUserRequest): Promise<UserResponse> {
+        return this.service.create(request)
+    }
+}
+`
+            const exposures = detector.detectExposures(
+                code,
+                "src/infrastructure/controllers/UserController.ts",
+                "infrastructure",
+            )
+
+            expect(exposures).toHaveLength(0)
+        })
+
+        it("should handle undefined layer", () => {
+            const code = `
+class UserController {
+    async getUser(id: string): Promise<User> {
+        return this.service.findById(id)
+    }
+}
+`
+            const exposures = detector.detectExposures(
+                code,
+                "src/controllers/UserController.ts",
+                undefined,
+            )
+
+            expect(exposures).toHaveLength(0)
+        })
+    })
+
+    describe("isDomainEntity", () => {
+        it("should identify PascalCase nouns as entities", () => {
+            expect(detector.isDomainEntity("User")).toBe(true)
+            expect(detector.isDomainEntity("Order")).toBe(true)
+            expect(detector.isDomainEntity("Product")).toBe(true)
+        })
+
+        it("should not identify DTOs", () => {
+            expect(detector.isDomainEntity("UserDto")).toBe(false)
+            expect(detector.isDomainEntity("UserDTO")).toBe(false)
+            expect(detector.isDomainEntity("UserResponse")).toBe(false)
+            expect(detector.isDomainEntity("CreateUserRequest")).toBe(false)
+        })
+
+        it("should not identify primitives", () => {
+            expect(detector.isDomainEntity("string")).toBe(false)
+            expect(detector.isDomainEntity("number")).toBe(false)
+            expect(detector.isDomainEntity("boolean")).toBe(false)
+            expect(detector.isDomainEntity("void")).toBe(false)
+            expect(detector.isDomainEntity("any")).toBe(false)
+            expect(detector.isDomainEntity("unknown")).toBe(false)
+        })
+
+        it("should handle Promise wrapped types", () => {
+            expect(detector.isDomainEntity("Promise<User>")).toBe(true)
+            expect(detector.isDomainEntity("Promise<UserDto>")).toBe(false)
+        })
+
+        it("should handle array types", () => {
+            expect(detector.isDomainEntity("User[]")).toBe(true)
+            expect(detector.isDomainEntity("UserDto[]")).toBe(false)
+        })
+
+        it("should handle union types", () => {
+            expect(detector.isDomainEntity("User | null")).toBe(true)
+            expect(detector.isDomainEntity("UserDto | null")).toBe(false)
+        })
+
+        it("should not identify non-PascalCase", () => {
+            expect(detector.isDomainEntity("user")).toBe(false)
+            expect(detector.isDomainEntity("USER")).toBe(false)
+            expect(detector.isDomainEntity("user_entity")).toBe(false)
+        })
+
+        it("should handle empty strings", () => {
+            expect(detector.isDomainEntity("")).toBe(false)
+            expect(detector.isDomainEntity("   ")).toBe(false)
+        })
+
+        it("should identify Command/Query/Result suffixes as allowed", () => {
+            expect(detector.isDomainEntity("CreateUserCommand")).toBe(false)
+            expect(detector.isDomainEntity("GetUserQuery")).toBe(false)
+            expect(detector.isDomainEntity("UserResult")).toBe(false)
+        })
+    })
+
+    describe("Real-world scenarios", () => {
+        it("should detect User entity exposure in REST API", () => {
+            const code = `
+class UserController {
+    async getUser(req: Request, res: Response): Promise<User> {
+        const user = await this.userService.findById(req.params.id)
+        return user
+    }
+}
+`
+            const exposures = detector.detectExposures(
+                code,
+                "src/infrastructure/controllers/UserController.ts",
+                "infrastructure",
+            )
+
+            expect(exposures).toHaveLength(1)
+            expect(exposures[0].entityName).toBe("User")
+            expect(exposures[0].getMessage()).toContain("returns domain entity 'User'")
+        })
+
+        it("should detect Order entity exposure in GraphQL resolver", () => {
+            const code = `
+class OrderResolver {
+    async getOrder(id: string): Promise<Order> {
+        return this.orderService.findById(id)
+    }
+}
+`
+            const exposures = detector.detectExposures(
+                code,
+                "src/infrastructure/resolvers/OrderResolver.ts",
+                "infrastructure",
+            )
+
+            expect(exposures).toHaveLength(1)
+            expect(exposures[0].entityName).toBe("Order")
+        })
+
+        it("should allow DTO usage in controller", () => {
+            const code = `
+class UserController {
+    async getUser(id: string): Promise<UserResponseDto> {
+        const user = await this.userService.findById(id)
+        return UserMapper.toDto(user)
+    }
+
+    async createUser(request: CreateUserRequest): Promise<UserResponseDto> {
+        const user = await this.userService.create(request)
+        return UserMapper.toDto(user)
+    }
+}
+`
+            const exposures = detector.detectExposures(
+                code,
+                "src/infrastructure/controllers/UserController.ts",
+                "infrastructure",
+            )
+
+            expect(exposures).toHaveLength(0)
+        })
+
+        it("should detect mixed exposures and DTOs", () => {
+            const code = `
+class UserController {
+    async getUser(id: string): Promise<User> {
+        return this.userService.findById(id)
+    }
+
+    async listUsers(): Promise<UserListResponse> {
+        const users = await this.userService.findAll()
+        return UserMapper.toListDto(users)
+    }
+}
+`
+            const exposures = detector.detectExposures(
+                code,
+                "src/infrastructure/controllers/UserController.ts",
+                "infrastructure",
+            )
+
+            expect(exposures).toHaveLength(1)
+            expect(exposures[0].methodName).toBe("getUser")
+        })
+
+        it("should provide helpful suggestions", () => {
+            const code = `
+class UserController {
+    async getUser(id: string): Promise<User> {
+        return this.userService.findById(id)
+    }
+}
+`
+            const exposures = detector.detectExposures(
+                code,
+                "src/infrastructure/controllers/UserController.ts",
+                "infrastructure",
+            )
+
+            expect(exposures[0].getSuggestion()).toContain("UserResponseDto")
+            expect(exposures[0].getSuggestion()).toContain("mapper")
+        })
+    })
+})

packages/guardian/tests/RepositoryPatternDetector.test.ts

@@ -0,0 +1,515 @@
+import { describe, it, expect, beforeEach } from "vitest"
+import { RepositoryPatternDetector } from "../src/infrastructure/analyzers/RepositoryPatternDetector"
+import { REPOSITORY_VIOLATION_TYPES } from "../src/shared/constants/rules"
+
+describe("RepositoryPatternDetector", () => {
+    let detector: RepositoryPatternDetector
+
+    beforeEach(() => {
+        detector = new RepositoryPatternDetector()
+    })
+
+    describe("detectViolations - ORM Types in Interface", () => {
+        it("should detect Prisma types in repository interface", () => {
+            const code = `
+interface IUserRepository {
+    findOne(query: Prisma.UserWhereInput): Promise<User>
+    create(data: Prisma.UserCreateInput): Promise<User>
+}
+`
+            const violations = detector.detectViolations(
+                code,
+                "src/domain/repositories/IUserRepository.ts",
+                "domain",
+            )
+
+            expect(violations.length).toBeGreaterThan(0)
+            const ormViolations = violations.filter(
+                (v) => v.violationType === REPOSITORY_VIOLATION_TYPES.ORM_TYPE_IN_INTERFACE,
+            )
+            expect(ormViolations.length).toBeGreaterThan(0)
+            expect(ormViolations[0].getMessage()).toContain("ORM-specific type")
+        })
+
+        it("should detect TypeORM decorators in repository interface", () => {
+            const code = `
+interface IUserRepository {
+    @Column()
+    findById(id: string): Promise<User>
+}
+`
+            const violations = detector.detectViolations(
+                code,
+                "src/domain/repositories/IUserRepository.ts",
+                "domain",
+            )
+
+            const ormViolations = violations.filter(
+                (v) => v.violationType === REPOSITORY_VIOLATION_TYPES.ORM_TYPE_IN_INTERFACE,
+            )
+            expect(ormViolations.length).toBeGreaterThan(0)
+        })
+
+        it("should detect Mongoose types in repository interface", () => {
+            const code = `
+interface IUserRepository {
+    find(query: Model<User>): Promise<User[]>
+    findOne(query: Schema): Promise<User>
+}
+`
+            const violations = detector.detectViolations(
+                code,
+                "src/domain/repositories/IUserRepository.ts",
+                "domain",
+            )
+
+            const ormViolations = violations.filter(
+                (v) => v.violationType === REPOSITORY_VIOLATION_TYPES.ORM_TYPE_IN_INTERFACE,
+            )
+            expect(ormViolations.length).toBeGreaterThan(0)
+        })
+
+        it("should not detect ORM types in clean interface", () => {
+            const code = `
+interface IUserRepository {
+    findById(id: UserId): Promise<User | null>
+    save(user: User): Promise<void>
+    delete(id: UserId): Promise<void>
+}
+`
+            const violations = detector.detectViolations(
+                code,
+                "src/domain/repositories/IUserRepository.ts",
+                "domain",
+            )
+
+            const ormViolations = violations.filter(
+                (v) => v.violationType === REPOSITORY_VIOLATION_TYPES.ORM_TYPE_IN_INTERFACE,
+            )
+            expect(ormViolations).toHaveLength(0)
+        })
+    })
+
+    describe("detectViolations - Concrete Repository in Use Case", () => {
+        it("should detect concrete repository in constructor", () => {
+            const code = `
+class CreateUser {
+    constructor(private userRepo: PrismaUserRepository) {}
+}
+`
+            const violations = detector.detectViolations(
+                code,
+                "src/application/use-cases/CreateUser.ts",
+                "application",
+            )
+
+            const concreteViolations = violations.filter(
+                (v) =>
+                    v.violationType === REPOSITORY_VIOLATION_TYPES.CONCRETE_REPOSITORY_IN_USE_CASE,
+            )
+            expect(concreteViolations).toHaveLength(1)
+            expect(concreteViolations[0].repositoryName).toBe("PrismaUserRepository")
+        })
+
+        it("should detect concrete repository as field", () => {
+            const code = `
+class CreateUser {
+    private userRepo: MongoUserRepository
+}
+`
+            const violations = detector.detectViolations(
+                code,
+                "src/application/use-cases/CreateUser.ts",
+                "application",
+            )
+
+            const concreteViolations = violations.filter(
+                (v) =>
+                    v.violationType === REPOSITORY_VIOLATION_TYPES.CONCRETE_REPOSITORY_IN_USE_CASE,
+            )
+            expect(concreteViolations).toHaveLength(1)
+        })
+
+        it("should not detect interface in constructor", () => {
+            const code = `
+class CreateUser {
+    constructor(private userRepo: IUserRepository) {}
+}
+`
+            const violations = detector.detectViolations(
+                code,
+                "src/application/use-cases/CreateUser.ts",
+                "application",
+            )
+
+            const concreteViolations = violations.filter(
+                (v) =>
+                    v.violationType === REPOSITORY_VIOLATION_TYPES.CONCRETE_REPOSITORY_IN_USE_CASE,
+            )
+            expect(concreteViolations).toHaveLength(0)
+        })
+    })
+
+    describe("detectViolations - new Repository() in Use Case", () => {
+        it("should detect repository instantiation with new", () => {
+            const code = `
+class CreateUser {
+    async execute(data: CreateUserRequest) {
+        const repo = new UserRepository()
+        await repo.save(user)
+    }
+}
+`
+            const violations = detector.detectViolations(
+                code,
+                "src/application/use-cases/CreateUser.ts",
+                "application",
+            )
+
+            const newRepoViolations = violations.filter(
+                (v) => v.violationType === REPOSITORY_VIOLATION_TYPES.NEW_REPOSITORY_IN_USE_CASE,
+            )
+            expect(newRepoViolations).toHaveLength(1)
+            expect(newRepoViolations[0].repositoryName).toBe("UserRepository")
+        })
+
+        it("should detect multiple repository instantiations", () => {
+            const code = `
+class ComplexUseCase {
+    async execute() {
+        const userRepo = new UserRepository()
+        const orderRepo = new OrderRepository()
+        await userRepo.save(user)
+        await orderRepo.save(order)
+    }
+}
+`
+            const violations = detector.detectViolations(
+                code,
+                "src/application/use-cases/ComplexUseCase.ts",
+                "application",
+            )
+
+            const newRepoViolations = violations.filter(
+                (v) => v.violationType === REPOSITORY_VIOLATION_TYPES.NEW_REPOSITORY_IN_USE_CASE,
+            )
+            expect(newRepoViolations).toHaveLength(2)
+        })
+
+        it("should not detect commented out new Repository()", () => {
+            const code = `
+class CreateUser {
+    async execute(data: CreateUserRequest) {
+        // const repo = new UserRepository()
+        await this.userRepo.save(user)
+    }
+}
+`
+            const violations = detector.detectViolations(
+                code,
+                "src/application/use-cases/CreateUser.ts",
+                "application",
+            )
+
+            const newRepoViolations = violations.filter(
+                (v) => v.violationType === REPOSITORY_VIOLATION_TYPES.NEW_REPOSITORY_IN_USE_CASE,
+            )
+            expect(newRepoViolations).toHaveLength(0)
+        })
+    })
+
+    describe("detectViolations - Non-Domain Method Names", () => {
+        it("should detect technical method names", () => {
+            const code = `
+interface IUserRepository {
+    findOne(id: string): Promise<User>
+    findMany(filter: any): Promise<User[]>
+    insert(user: User): Promise<void>
+    updateOne(id: string, data: any): Promise<void>
+}
+`
+            const violations = detector.detectViolations(
+                code,
+                "src/domain/repositories/IUserRepository.ts",
+                "domain",
+            )
+
+            const methodViolations = violations.filter(
+                (v) => v.violationType === REPOSITORY_VIOLATION_TYPES.NON_DOMAIN_METHOD_NAME,
+            )
+            expect(methodViolations.length).toBeGreaterThan(0)
+            expect(methodViolations.some((v) => v.methodName === "findOne")).toBe(true)
+            expect(methodViolations.some((v) => v.methodName === "insert")).toBe(true)
+        })
+
+        it("should not detect domain language method names", () => {
+            const code = `
+interface IUserRepository {
+    findById(id: UserId): Promise<User | null>
+    findByEmail(email: Email): Promise<User | null>
+    save(user: User): Promise<void>
+    delete(id: UserId): Promise<void>
+    search(criteria: SearchCriteria): Promise<User[]>
+}
+`
+            const violations = detector.detectViolations(
+                code,
+                "src/domain/repositories/IUserRepository.ts",
+                "domain",
+            )
+
+            const methodViolations = violations.filter(
+                (v) => v.violationType === REPOSITORY_VIOLATION_TYPES.NON_DOMAIN_METHOD_NAME,
+            )
+            expect(methodViolations).toHaveLength(0)
+        })
+
+        it("should detect SQL terminology", () => {
+            const code = `
+interface IUserRepository {
+    select(id: string): Promise<User>
+    query(filter: any): Promise<User[]>
+    execute(sql: string): Promise<any>
+}
+`
+            const violations = detector.detectViolations(
+                code,
+                "src/domain/repositories/IUserRepository.ts",
+                "domain",
+            )
+
+            const methodViolations = violations.filter(
+                (v) => v.violationType === REPOSITORY_VIOLATION_TYPES.NON_DOMAIN_METHOD_NAME,
+            )
+            expect(methodViolations.length).toBeGreaterThan(0)
+        })
+    })
+
+    describe("isOrmType", () => {
+        it("should identify Prisma types", () => {
+            expect(detector.isOrmType("Prisma.UserWhereInput")).toBe(true)
+            expect(detector.isOrmType("PrismaClient")).toBe(true)
+        })
+
+        it("should identify TypeORM decorators", () => {
+            expect(detector.isOrmType("@Entity")).toBe(true)
+            expect(detector.isOrmType("@Column")).toBe(true)
+            expect(detector.isOrmType("@ManyToOne")).toBe(true)
+        })
+
+        it("should identify Mongoose types", () => {
+            expect(detector.isOrmType("Schema")).toBe(true)
+            expect(detector.isOrmType("Model<User>")).toBe(true)
+            expect(detector.isOrmType("Document")).toBe(true)
+        })
+
+        it("should not identify domain types", () => {
+            expect(detector.isOrmType("User")).toBe(false)
+            expect(detector.isOrmType("UserId")).toBe(false)
+            expect(detector.isOrmType("Email")).toBe(false)
+        })
+    })
+
+    describe("isDomainMethodName", () => {
+        it("should identify domain method names", () => {
+            expect(detector.isDomainMethodName("findById")).toBe(true)
+            expect(detector.isDomainMethodName("findByEmail")).toBe(true)
+            expect(detector.isDomainMethodName("save")).toBe(true)
+            expect(detector.isDomainMethodName("delete")).toBe(true)
+            expect(detector.isDomainMethodName("create")).toBe(true)
+            expect(detector.isDomainMethodName("search")).toBe(true)
+        })
+
+        it("should reject technical method names", () => {
+            expect(detector.isDomainMethodName("findOne")).toBe(false)
+            expect(detector.isDomainMethodName("findMany")).toBe(false)
+            expect(detector.isDomainMethodName("insert")).toBe(false)
+            expect(detector.isDomainMethodName("updateOne")).toBe(false)
+            expect(detector.isDomainMethodName("query")).toBe(false)
+            expect(detector.isDomainMethodName("execute")).toBe(false)
+        })
+    })
+
+    describe("isRepositoryInterface", () => {
+        it("should identify repository interfaces in domain", () => {
+            expect(
+                detector.isRepositoryInterface(
+                    "src/domain/repositories/IUserRepository.ts",
+                    "domain",
+                ),
+            ).toBe(true)
+            expect(
+                detector.isRepositoryInterface(
+                    "src/domain/repositories/IOrderRepository.ts",
+                    "domain",
+                ),
+            ).toBe(true)
+        })
+
+        it("should not identify repository implementations in infrastructure", () => {
+            expect(
+                detector.isRepositoryInterface(
+                    "src/infrastructure/repositories/UserRepository.ts",
+                    "infrastructure",
+                ),
+            ).toBe(false)
+        })
+
+        it("should not identify non-repository files", () => {
+            expect(detector.isRepositoryInterface("src/domain/entities/User.ts", "domain")).toBe(
+                false,
+            )
+        })
+    })
+
+    describe("isUseCase", () => {
+        it("should identify use cases", () => {
+            expect(
+                detector.isUseCase("src/application/use-cases/CreateUser.ts", "application"),
+            ).toBe(true)
+            expect(
+                detector.isUseCase("src/application/use-cases/UpdateProfile.ts", "application"),
+            ).toBe(true)
+            expect(
+                detector.isUseCase("src/application/use-cases/DeleteOrder.ts", "application"),
+            ).toBe(true)
+        })
+
+        it("should not identify DTOs as use cases", () => {
+            expect(
+                detector.isUseCase("src/application/dtos/UserResponseDto.ts", "application"),
+            ).toBe(false)
+        })
+
+        it("should not identify use cases in wrong layer", () => {
+            expect(detector.isUseCase("src/domain/use-cases/CreateUser.ts", "domain")).toBe(false)
+        })
+    })
+
+    describe("getMessage and getSuggestion", () => {
+        it("should provide helpful message for ORM type violations", () => {
+            const code = `
+interface IUserRepository {
+    findOne(query: Prisma.UserWhereInput): Promise<User>
+}
+`
+            const violations = detector.detectViolations(
+                code,
+                "src/domain/repositories/IUserRepository.ts",
+                "domain",
+            )
+
+            const ormViolations = violations.filter(
+                (v) => v.violationType === REPOSITORY_VIOLATION_TYPES.ORM_TYPE_IN_INTERFACE,
+            )
+            expect(ormViolations[0].getMessage()).toContain("ORM-specific type")
+            expect(ormViolations[0].getSuggestion()).toContain("domain types")
+        })
+
+        it("should provide helpful message for concrete repository violations", () => {
+            const code = `
+class CreateUser {
+    constructor(private userRepo: PrismaUserRepository) {}
+}
+`
+            const violations = detector.detectViolations(
+                code,
+                "src/application/use-cases/CreateUser.ts",
+                "application",
+            )
+
+            const concreteViolations = violations.filter(
+                (v) =>
+                    v.violationType === REPOSITORY_VIOLATION_TYPES.CONCRETE_REPOSITORY_IN_USE_CASE,
+            )
+            expect(concreteViolations[0].getMessage()).toContain("concrete repository")
+            expect(concreteViolations[0].getSuggestion()).toContain("interface")
+        })
+
+        it("should provide helpful message for new repository violations", () => {
+            const code = `
+class CreateUser {
+    async execute() {
+        const repo = new UserRepository()
+    }
+}
+`
+            const violations = detector.detectViolations(
+                code,
+                "src/application/use-cases/CreateUser.ts",
+                "application",
+            )
+
+            const newRepoViolations = violations.filter(
+                (v) => v.violationType === REPOSITORY_VIOLATION_TYPES.NEW_REPOSITORY_IN_USE_CASE,
+            )
+            expect(newRepoViolations[0].getMessage()).toContain("new")
+            expect(newRepoViolations[0].getSuggestion()).toContain("dependency injection")
+        })
+
+        it("should provide helpful message for non-domain method violations", () => {
+            const code = `
+interface IUserRepository {
+    findOne(id: string): Promise<User>
+}
+`
+            const violations = detector.detectViolations(
+                code,
+                "src/domain/repositories/IUserRepository.ts",
+                "domain",
+            )
+
+            const methodViolations = violations.filter(
+                (v) => v.violationType === REPOSITORY_VIOLATION_TYPES.NON_DOMAIN_METHOD_NAME,
+            )
+            expect(methodViolations[0].getMessage()).toContain("technical name")
+            expect(methodViolations[0].getSuggestion()).toContain("domain language")
+        })
+    })
+
+    describe("Integration tests", () => {
+        it("should detect multiple violation types in same file", () => {
+            const code = `
+interface IUserRepository {
+    findOne(query: Prisma.UserWhereInput): Promise<User>
+    insert(user: User): Promise<void>
+    findById(id: UserId): Promise<User | null>
+}
+`
+            const violations = detector.detectViolations(
+                code,
+                "src/domain/repositories/IUserRepository.ts",
+                "domain",
+            )
+
+            expect(violations.length).toBeGreaterThan(1)
+            const types = violations.map((v) => v.violationType)
+            expect(types).toContain(REPOSITORY_VIOLATION_TYPES.ORM_TYPE_IN_INTERFACE)
+            expect(types).toContain(REPOSITORY_VIOLATION_TYPES.NON_DOMAIN_METHOD_NAME)
+        })
+
+        it("should detect all violations in complex use case", () => {
+            const code = `
+class CreateUser {
+    constructor(private userRepo: PrismaUserRepository) {}
+
+    async execute(data: CreateUserRequest) {
+        const repo = new OrderRepository()
+        await this.userRepo.save(user)
+        await repo.save(order)
+    }
+}
+`
+            const violations = detector.detectViolations(
+                code,
+                "src/application/use-cases/CreateUser.ts",
+                "application",
+            )
+
+            expect(violations.length).toBeGreaterThanOrEqual(2)
+            const types = violations.map((v) => v.violationType)
+            expect(types).toContain(REPOSITORY_VIOLATION_TYPES.CONCRETE_REPOSITORY_IN_USE_CASE)
+            expect(types).toContain(REPOSITORY_VIOLATION_TYPES.NEW_REPOSITORY_IN_USE_CASE)
+        })
+    })
+})