Marcus Ash, a design lead at Microsoft Windows, has revealed details about the development of the native speed test tool in Win11 26H2. The feature was designed and built by an employee in their spare time with the help of AI agents. An earlier version co-developed with Ookla was merely a wrapper around a Bing webpage, and only recently has a native tool matching the Windows style officially launched. Throughout the project, humans set the direction while AI handled execution and iteration, producing a usable prototype in just one day and ultimately delivering a product that conforms to Windows specifications and is visually unified with the Shell. Microsoft is betting on AI-assisted development, with the core goal being to rapidly transform concepts into products of real value and refusing to produce useless AI junk; the company has previously applied AI agents to multiple stages of internal tool development on several occasions.