Dreams Bank API

A distributed banking system API built with Elixir and Phoenix Framework, designed with a strong focus on reliability and scalability through clustering capabilities.

Overview

This project implements a robust banking system that leverages Elixir's distributed computing capabilities. The architecture is built around fault tolerance and horizontal scalability, allowing multiple nodes to work together seamlessly.

Key Features

Distributed Architecture

• Multi-node clustering using libcluster
• Automatic load balancing across nodes
• Fault-tolerant operations
• Node-aware transaction handling

Banking Operations

• Account management (creation, updates, deletion)
• Secure money transfers between accounts
• Deposits and withdrawals with consistency guarantees
• Real-time balance tracking

Development Approach

This project follows Test-Driven Development (TDD) principles strictly, with comprehensive test coverage for:

• Unit tests for all business logic
• Integration tests for API endpoints
• Property-based tests for critical operations
• Clustered operations testing

Current test coverage: +90% (tracked by Coveralls)

Technical Requirements

• Elixir 1.17.3
• Erlang/OTP 27.1
• PostgreSQL 14

Getting Started

Local Development Setup

1. Install dependencies:

mix deps.get

2. Setup database:

mix setup

3. Run tests to ensure everything is working:

mix test

Running in Cluster Mode

To start multiple nodes in development:

# Terminal 1 - Start first node
PORT=4001 iex --name node1@127.0.0.1 -S mix phx.server

# Terminal 2 - Start second node
PORT=4002 iex --name node2@127.0.0.1 -S mix phx.server

# Terminal 3 - Start third node
PORT=4003 iex --name node3@127.0.0.1 -S mix phx.server

The nodes will automatically discover each other and form a cluster.

Testing

The project emphasizes thorough testing:

# Run all tests
mix test

# Run with coverage report
mix coveralls.html

# Run Credo for code analysis
mix credo --strict

# Run full check (format, credo)
mix check

To DO:

• API Documentation