Building a Banking API with Go

Why Go for a Banking API

Go is a good fit for backend APIs because it is simple, fast, explicit, and easy to deploy. A banking API is a useful practice project because it requires authentication, ownership rules, database consistency, and careful error handling.

Core Backend Pieces

The project included:

• Configuration management
• HTTP middleware
• Response helpers
• PostgreSQL repositories
• Database migrations
• Register and login flows
• Protected routes
• Account ownership checks
• Safe database transactions

Transaction Safety

Banking-style operations need transaction boundaries. A transfer should not debit one account unless the matching credit also succeeds.

tx, err := db.Begin(ctx)
if err != nil {
    return err
}
defer tx.Rollback(ctx)

// debit, credit, write ledger entry

return tx.Commit(ctx)

What I Practiced

This project strengthened my understanding of clean package structure, repository patterns, middleware, and defensive backend design.