What architectural patterns have you applied in your work?

In my work with Go, I have applied several architectural patterns that help create maintainable and scalable code:

• Clean Architecture / Hexagonal Architecture — dividing the application into layers (interfaces, business logic, infrastructure) for independence from external details and ease of testing.

• Repository Pattern — an abstraction of data access, allowing changing the data source without affecting business logic.

• Dependency Injection — injecting dependencies through constructors or interfaces to enhance modularity and testability.

• Factory Pattern — creating objects considering configuration or context, which simplifies managing complex dependencies.

• Middleware Pattern (especially in HTTP servers) — for processing requests through a chain of handlers.

An example of a simple repository in Go:

 type UserRepository interface {
     GetByID(id int) (*User, error)
 }

type userRepo struct {
     db *sql.DB
 }

func (r *userRepo) GetByID(id int) (*User, error) {
     // implementation of database query
 }

These patterns help build flexible and easily extendable applications.