Microsoft’s Core Operating System Division (COSD) is somewhat of a black hole to many outside (and even inside) the Redmond software maker. Charged with the amorphous goal of ensuring Windows “engineering excellence,” the five-year-old COSD group creates the core components at the heart of Windows.

Jon DeVaan — the “mystery man” behind Windows 7 — is the Senior Vice President in charge of COSD. I had a chance to ask DeVaan some questions last week about how COSD works and about one of COSD’s better-known (if still largely misunderstood) initiatives: MinWin.

COSD was created in December 2003 during the reign of then-group-vice-president-of-platforms, Jim Allchin. COSD’s mission was to help the Windows team hone its architecture development and overall processes. Since its inception, the COSD team has focused on developing the “guts” of Windows: the kernel, I/O (input-output) system; core devices; setup; virtualization; the driver framework; and all the build properties.

Full Transcript