The story of Redis and KeyDB encapsulates a pivotal moment in open-source software history, where technical innovation collided with the economic realities of sustaining widely used infrastructure. Redis, created in 2009 by Salvatore Sanfilippo (Antirez), emerged as a revolutionary in-memory data store, prized for its speed and simplicity. Released under the permissive BSD-3 license, it became a foundational technology for real-time applications, powering everything from social media feeds to online gaming. Its open-source nature fostered widespread adoption, but also enabled major cloud providers like Amazon, Google, and Microsoft to profit from managed Redis services without proportionally contributing to its development. This imbalance led to what is often described as the ’tragedy of the commons,’ where the project’s maintainers at Redis Inc. struggled to fund ongoing innovation. In response, beginning in 2018 with module licensing changes and culminating in 2024 with a shift of the core software to the restrictive Server Side Public License (SSPL) and Redis Source Available License (RSAL), Redis Inc. moved away from traditional open source. These licenses effectively prevented cloud providers from offering competitive managed services unless they open-sourced their own proprietary infrastructure, a non-starter for most. This decision triggered a crisis in the developer community, forcing businesses to confront legal and operational uncertainty. In anticipation of such commercial restrictions, EQ Technologies launched KeyDB in 2019 as a direct, open-source alternative. Built as a high-performance fork of Redis, KeyDB introduced critical technical advancements, most notably multithreading, allowing it to handle significantly higher loads by utilizing multiple CPU cores simultaneously—unlike Redis’s single-threaded architecture. It also offered Active-Active replication for seamless failover and a flash-friendly design for efficient SSD use, expanding its applicability. Crucially, KeyDB maintained full command compatibility with Redis and adhered to the original BSD-3 license, ensuring true freedom for commercial use and redistribution. The 2024 license change dramatically accelerated KeyDB’s relevance, transforming it from a performance-focused alternative into a vital lifeline for organizations committed to open-source principles. Its adoption has grown steadily, supported by a community valuing both technical superiority and licensing freedom. However, KeyDB faces challenges in scaling its ecosystem, optimizing performance across diverse environments, and establishing a sustainable business model without compromising its open ethos. This saga underscores a broader industry debate: how can foundational open-source projects achieve financial sustainability without alienating the community that sustains them? The divergence between Redis and KeyDB illustrates the tension between ’source-available’ models and pure open source, with profound implications for innovation, competition, and the cost and reliability of digital services. Ultimately, the outcome will influence the architecture of future applications, empowering smaller developers and startups to build without fear of sudden licensing shifts, while reminding the tech world that the governance of shared digital resources carries deep ethical and practical consequences.