The document details the development of Moneybird, a simple invoicing application for small businesses, launched live in October 2008 after a development process that began in April 2008. It discusses the application's features, including invoice management, contact management, and an innovative AJAX interface, and also outlines the technologies used, including Rails 2.2 and integration testing with RSpec and Cucumber. Additionally, it addresses challenges faced, such as PDF generation issues and model complexity, alongside employing modularity through a 'concerned_with' approach to enhance code maintainability.