Lokstra vs NestJS - Framework Comparison

Detailed comparison between Lokstra (Go) and NestJS (TypeScript/Node.js)

Both Lokstra and NestJS are enterprise-grade frameworks that emphasize dependency injection, modular architecture, and convention over configuration. Here’s how they compare:

🎯 Quick Overview

🏗️ Architecture Comparison

Lokstra: Service-Oriented Architecture

// 1. Define Service
type UserService struct {
    db *Database
}

func (s *UserService) GetAll() ([]User, error) {
    return s.db.Query("SELECT * FROM users")
}

func (s *UserService) GetByID(id string) (*User, error) {
    return s.db.QueryOne("SELECT * FROM users WHERE id = ?", id)
}

// 2. Register Service Factory
lokstra_registry.RegisterServiceType(
    "user-service-factory",
    NewUserService,
    nil,
    deploy.WithResource("user", "users"),
    deploy.WithConvention("rest"),
)

// 3. Auto-generate Router
userRouter := lokstra_registry.NewRouterFromServiceType("user-service-factory")
// Creates: GET /users, GET /users/{id}, etc.

NestJS: Module + Controller Architecture

// 1. Define Service
@Injectable()
export class UserService {
  constructor(private db: Database) {}

  async getAll(): Promise<User[]> {
    return this.db.query('SELECT * FROM users');
  }

  async getById(id: string): Promise<User> {
    return this.db.queryOne('SELECT * FROM users WHERE id = ?', [id]);
  }
}

// 2. Define Controller
@Controller('users')
export class UserController {
  constructor(private userService: UserService) {}

  @Get()
  async getAll() {
    return this.userService.getAll();
  }

  @Get(':id')
  async getById(@Param('id') id: string) {
    return this.userService.getById(id);
  }
}

// 3. Module Registration
@Module({
  controllers: [UserController],
  providers: [UserService],
})
export class UserModule {}

🔌 Dependency Injection Comparison

Lokstra: Lazy Loading with Generics

// Type-safe, lazy loading
var userService = service.LazyLoad[*UserService]("user-service")
var database = service.LazyLoad[*Database]("database")

func handler() {
    // Loaded on first access, cached forever
    users := userService.MustGet().GetAll()
}

// Factory with dependencies
func NewUserService() *UserService {
    return &UserService{
        db: service.LazyLoad[*Database]("database"),
    }
}

// Register with dependencies
lokstra_registry.RegisterServiceFactory("user-service", NewUserService)
lokstra_registry.RegisterServiceFactory("database", NewDatabase)

Lokstra DI Advantages:

• ✅ Type-safe: Compile-time type checking with generics
• ✅ Lazy: Services created only when needed
• ✅ Performance: No reflection overhead
• ✅ Simple: No decorators, just functions

NestJS: Decorator-based DI

// Constructor injection
@Injectable()
export class UserService {
  constructor(
    private database: Database,
    private logger: Logger,
  ) {}
}

// Provider registration
@Module({
  providers: [
    UserService,
    Database,
    Logger,
  ],
})
export class AppModule {}

NestJS DI Advantages:

• ✅ Familiar: Similar to Angular/Spring
• ✅ Automatic: Dependency resolution via reflection
• ✅ Rich ecosystem: Many built-in providers
• ⚠️ Runtime overhead: Reflection-based

🚦 Router Generation Comparison

Lokstra: Convention-based from Service Methods

// Service method signatures determine routes
func (s *UserService) GetAll(p *GetAllParams) ([]User, error)     // GET /users
func (s *UserService) GetByID(p *GetByIDParams) (*User, error)    // GET /users/{id}
func (s *UserService) Create(p *CreateParams) (*User, error)      // POST /users
func (s *UserService) Update(p *UpdateParams) (*User, error)      // PUT /users/{id}
func (s *UserService) Delete(p *DeleteParams) error              // DELETE /users/{id}

// Auto-router generation
router := lokstra_registry.NewRouterFromServiceType("user-service-factory")

Lokstra Approach:

• ✅ Zero boilerplate: No controller layer needed
• ✅ Convention over configuration: Method names → HTTP routes
• ✅ Type-safe parameters: Struct-based parameter binding
• ✅ Flexible: Can override routes if needed

NestJS: Decorator-driven Routes

@Controller('users')
export class UserController {
  @Get()                    // GET /users
  getAll() { ... }

  @Get(':id')              // GET /users/:id
  getById(@Param('id') id: string) { ... }

  @Post()                  // POST /users
  create(@Body() data: CreateUserDto) { ... }

  @Put(':id')              // PUT /users/:id
  update(@Param('id') id: string, @Body() data: UpdateUserDto) { ... }

  @Delete(':id')           // DELETE /users/:id
  delete(@Param('id') id: string) { ... }
}

NestJS Approach:

• ✅ Explicit: Clear route definitions
• ✅ Flexible: Rich decorator options
• ✅ Validation: Built-in DTO validation
• ⚠️ Boilerplate: Need controller layer + service layer

📝 Configuration & Deployment

Lokstra: YAML + Code Configuration

# config.yaml - Deployment topology
service-definitions:
  user-service:
    type: user-service-factory
    depends-on: [database]

deployments:
  monolith:
    servers:
      api-server:
        addr: ":8080"
        published-services: [user-service, order-service]
  
  microservices:
    servers:
      user-service:
        addr: ":8001"
        published-services: [user-service]
      order-service:
        addr: ":8002"
        published-services: [order-service]

# Same binary, different topologies!
./app -server=monolith.api-server      # Monolith
./app -server=microservices.user-service  # Microservice

Lokstra Deployment:

• ✅ Zero-code deployment changes: Same binary, different config
• ✅ Flexible topology: Monolith ↔ Microservices without code changes
• ✅ Environment overrides: Command-line params > ENV > YAML defaults

NestJS: Code + Environment Configuration

// Different apps for different deployments
@Module({
  imports: [UserModule, OrderModule, PaymentModule],
})
export class MonolithApp {}

@Module({
  imports: [UserModule],
})
export class UserMicroservice {}

@Module({
  imports: [OrderModule],
})
export class OrderMicroservice {}

// Different main.ts files or conditional imports
async function bootstrap() {
  const app = await NestFactory.create(
    process.env.SERVICE_TYPE === 'user' ? UserMicroservice : MonolithApp
  );
  await app.listen(process.env.PORT || 3000);
}

NestJS Deployment:

• ⚠️ Code changes required: Different modules for different deployments
• ✅ Rich configuration: ConfigModule, environment validation
• ✅ Good tooling: CLI, testing utilities

⚡ Performance Comparison

Lokstra (Go)

• ✅ Fast startup: Compiled binary, instant startup
• ✅ Low memory: Efficient memory usage
• ✅ High throughput: Go’s goroutines for concurrency
• ✅ No GC pauses: Predictable performance
• ✅ Small binaries: Single executable file

NestJS (Node.js)

• ⚠️ Slower startup: Runtime compilation, module resolution
• ⚠️ Higher memory: V8 engine overhead
• ✅ Good throughput: Event loop for I/O-bound tasks
• ⚠️ GC pauses: V8 garbage collection
• ⚠️ Larger deployments: node_modules + runtime

🧪 Testing Comparison

Lokstra Testing

func TestUserService(t *testing.T) {
    // Mock dependencies
    mockDB := &MockDatabase{}
    
    // Create service with mocked deps
    service := &UserService{db: mockDB}
    
    // Test service methods
    users, err := service.GetAll(&GetAllParams{})
    assert.NoError(t, err)
    assert.Len(t, users, 2)
}

// Integration testing with registry
func TestUserServiceWithRegistry(t *testing.T) {
    lokstra_registry.RegisterServiceFactory("database", NewMockDatabase)
    lokstra_registry.RegisterServiceFactory("user-service", NewUserService)
    
    userService := lokstra_registry.GetService[*UserService]("user-service")
    // Test with real DI container
}

NestJS Testing

describe('UserService', () => {
  let service: UserService;
  let database: Database;

  beforeEach(async () => {
    const module: TestingModule = await Test.createTestingModule({
      providers: [
        UserService,
        {
          provide: Database,
          useValue: mockDatabase,
        },
      ],
    }).compile();

    service = module.get<UserService>(UserService);
    database = module.get<Database>(Database);
  });

  it('should return users', async () => {
    const users = await service.getAll();
    expect(users).toHaveLength(2);
  });
});

🎯 When to Choose Which?

Choose Lokstra When:

• ✅ Performance is critical: Need fast startup and low latency
• ✅ Deployment flexibility: Want monolith ↔ microservices flexibility
• ✅ Type safety: Prefer compile-time safety over runtime flexibility
• ✅ Simple deployment: Want single binary deployment
• ✅ Go ecosystem: Team familiar with Go
• ✅ Zero boilerplate: Want auto-router without controller layer

Choose NestJS When:

• ✅ Rich ecosystem: Need extensive package ecosystem
• ✅ Team expertise: Team familiar with TypeScript/Angular
• ✅ Rapid development: Need quick prototyping with decorators
• ✅ Frontend integration: Building full-stack TypeScript apps
• ✅ Mature tooling: Need CLI, testing, and debugging tools
• ✅ Enterprise patterns: Want familiar Spring Boot-like patterns

🏆 Summary Comparison

🚀 Migration Path

From NestJS to Lokstra:

// NestJS Controller + Service
@Controller('users')
export class UserController {
  constructor(private userService: UserService) {}
  
  @Get()
  getAll() { return this.userService.getAll(); }
}

@Injectable()
export class UserService {
  getAll() { /* logic */ }
}

// Lokstra Service (no controller needed!)
type UserService struct {}

func (s *UserService) GetAll(p *GetAllParams) ([]User, error) {
    // Same logic, auto-generates routes
}

// Register and auto-route
lokstra_registry.RegisterServiceType("user-service-factory", NewUserService, nil,
    deploy.WithResource("user", "users"))

Migration benefits:

• ✅ Remove controller layer: Direct service → HTTP mapping
• ✅ Better performance: Compiled Go vs runtime TypeScript
• ✅ Flexible deployment: One binary, multiple topologies

Both frameworks are excellent for enterprise applications. Choose based on your team’s expertise, performance requirements, and ecosystem preferences!