Open source IAM is able to adapt to the modern Web where legacy IAM vendors cannot, for several key reasons. Open source IAM products are designed to be unified, lightweight, modular, and scalable. This allows them to quickly and easily adapt to the ever-changing, ever-growing requirements of the modern Web. Legacy products were built by acquisition over time, making their solutions inherently piecemeal, bulky, and complex???and thus ultimately time-consuming to implement and inefficient in practice.