Go Banking Backend

A secure and scalable banking backend system built with Go (Golang). This project is open-source and designed for learning, extension, and real-world use. It uses PostgreSQL as the main database and integrates with a locally hosted instance of the Frankfurter API for real-time currency exchange rates.

Features

• User registration and authentication
• Bank account creation and management
• Deposits, withdrawals, and balance tracking
• Money transfers between accounts
• Multi-currency support
• Real-time currency conversion (Frankfurter API)
• PostgreSQL for persistent storage
• RESTful API architecture
• Modular and clean folder structure

Tech Stack

Component	Technology
Language	Go (Golang)
Database	PostgreSQL
Currency Rates	Frankfurter API (self-hosted)
API Style	REST
Dependency Mgmt	Go Modules
Environment Vars	.env file

Project Structure

go-banking-backend/
├── account/
│   └── account.go
├── auth/
│   ├── auth.go
│   ├── errors.go
│   ├── helpers.go
│   ├── logger.go
│   ├── ratelimiter.go
│   ├── responses.go
│   └── validation.go
├── currency/
│   └── currency.go
├── db/
│   └── init.sql
├── transactions/
│   ├── deposit.go
│   └── transaction.go
├── .env.template
├── .gitignore
├── docker-compose.yml
├── Dockerfile
├── go.mod
├── go.sum
├── LICENSE
├── main.go
└── README.md

Setup & Installation

1. Clone the repository

git clone https://github.com/ELadrimonos/go-banking-backend.git
cd go-banking-backend

2. Configure environment variables

Create a .env file from the .env.template template:

POSTGRES_USER=user
POSTGRES_PASSWORD=password
POSTGRES_DB=banking

3. Start the services

docker-compose up --build

API Endpoints (Examples)

Method	Endpoint	Description
POST	/signup	Register a new user
POST	/login	User login
POST	/change-password	Change user password
GET	/accounts	Get user accounts
POST	/create-account	Create a new bank account
POST	/deposit	Deposit money into an account
GET	/convert?from=USD&to=EUR&amount=100	Convert an amount from one currency to another

Currency Exchange Integration

The system communicates with a locally hosted Frankfurter API for currency conversion. Example request:

GET http://localhost:8081/latest?amount=100&from=USD&to=EUR

License

This project is open-source under the MIT License.

Contributing

1. Fork the repository
2. Create a feature branch (git checkout -b feature-name)
3. Commit your changes
4. Open a Pull Request