Internal Developer Platforms (IDPs) are becoming mainstream as companies seek to improve developer experience and reduce DevOps overhead. They enable self-service for developers, automate setup, and provide a platform for abstracting away infrastructure complexities. The "build vs buy" question is crucial, with factors such as cost, control, connectivity, maintenance, and tradeoffs in mind. Building an IDP from scratch can be costly, requiring significant resources and time, while using a commercial framework like Humanitec offers a more cost-effective solution with instant impact on workflows and Ops overhead. Key considerations include the need for a dedicated Platform team, security, feature control, open source, and opinionated flows. Ultimately, most companies will benefit from buying an IDP, especially as they grow beyond 20 developers, to avoid overkill and prioritize business value-added activities.