Invoice Ninja

Invoice Ninja is an open-source and self-hosted web application that provides tools for invoicing and expense management. It is designed for freelancers and small businesses to manage their billing cycles and financial tracking. The software is deployed as a web application on a server, with supporting clients available for desktop and mobile devices to ensure access across different hardware environments.

Users can choose between a hosted SaaS version for quick setup or a self-hosted installation for full control over their server infrastructure and data. The system includes a dedicated client portal where customers can view and interact with their invoices and quotes. It is built using PHP and the Laravel framework, providing a structured environment for managing business finances and client relationships.

Key features

• Creation of professional invoices and quotes
• Tracking of business expenses
• Integration of online payment processing
• Project and task management
• Dedicated client portal for customer access
• Time tracking for billable hours
• API access via available SDKs
• Support for e-invoicing

The application architecture relies on Laravel for the API and client portal. It utilizes a repository pattern and service classes to handle business logic, such as invoice creation, default filling, and inventory adjustment. When an invoice is created, the system fires events to notify listeners for non-blocking sub-tasks before transforming the data into a response via Fractal. This modular approach allows developers to extend the functionality of the software through the provided SDKs and API endpoints.

For those who require a fully branded experience, the software offers a white-label license to remove the Invoice Ninja branding from all client-facing parts of the application. The development environment supports PHPUnit for testing, ensuring that new modifications maintain system stability. This makes the software suitable for developers who need to integrate billing into larger business workflows.

Invoice Ninja is a comprehensive financial tool for independent contractors and small enterprises.