Introduction

MinStack is a collection of small, independent Go modules for building backend services. Each module does one thing and composes cleanly with the others.

Philosophy

• Minimal — no unnecessary abstractions, no hidden config
• Composable — combine only the modules you need
• Explicit — every dependency is declared, every behavior is visible

Dependency Injection with Uber FX

MinStack is built on top of Uber FX — a production-grade dependency injection framework developed and used at Uber. Every MinStack module exposes a single Module() function that registers its providers and hooks into the FX lifecycle.

app := core.New(
    gin.Module(),    // provides *gin.Engine
    postgres.Module(), // provides *gorm.DB
)
app.Run()

When you call app.Run(), FX:

1. Resolves all declared dependencies
2. Calls OnStart hooks in order (e.g. opens DB connection, starts HTTP server)
3. Blocks until a shutdown signal is received
4. Calls OnStop hooks in reverse order (graceful shutdown)

No global state. No init() surprises. If a dependency is missing or a constructor fails, the app refuses to start with a clear error — not a runtime panic.

Providing your own dependencies

type UserService struct{ db *gorm.DB }

func NewUserService(db *gorm.DB) *UserService {
    return &UserService{db: db}
}

app.Provide(NewUserService) // FX injects *gorm.DB automatically

Running startup logic

func runMigrations(db *gorm.DB) error {
    return db.AutoMigrate(&User{})
}

app.Invoke(runMigrations) // called at startup, dependencies resolved automatically

Modules

Module	Purpose
core	Application bootstrap — required by all
gin	HTTP server using Gin
cli	One-shot CLI process that exits when done
mysql	MySQL database via GORM
postgres	PostgreSQL database via GORM
sqlite	SQLite database via GORM (no CGO)