Probably one of the best texts I've read on Twitter recently, this article on news.microsoft.com tells the story of Dave Cutler a Microsoft Senior Technical Fellow who played a central role in the development of DEC's VMS, Windows NT, Microsoft Azure and the hypervisor for the XBox One.
Here are some quotes from the article that particularly caught my attention.
When all is said and done, much more is said than done.
On the need to find the right balance between agility and doing proper analysis.
The small, high-powered team of former DEC engineers and one existing Microsoft employee (Steve Wood) began by spending six months creating a specification for the operating system – the specification that now resides in the Smithsonian Institute.
Empowered teams should be aware of business constraints and be ready to adapt.
At first, the team was going to target the expanded OS/2 32-bit API as the main “personality” of the system, but later they changed to Windows 32 when Windows 3.1 proved to be so popular (16 million copies sold in six months). As a result, the team had to expand the Windows 16 API to a Windows 32 API and redesign the entire graphics subsystem. The team also had to hit the reset button on hardware when it changed its initial hardware target from the Intel i860 XR RISC processor to the MIPS R3000.
Accepting that you have to live with your legacy.
“We wanted to write a modern operating system from scratch,” Myhrvold said. “We also wanted to have some level of backward compatibility with previous systems and that’s where everything was difficult. But we came up with a variety of methods to do it, some in my group, some in Dave’s… It’s always hard to have backward compatibility when you’re doing something brand new and you’d love to throw the whole past out. But for customers it’s really important to have that bridge to the past. Figuring out how we could do that so that existing Windows applications could get moved over and run on NT was pretty important.” Bell believes Cutler is the only engineer with the confidence to pull off NT as he did. “Almost anyone who would have been good enough to do NT would have insisted on a blank sheet for the spec,” Bell said. “Dave appreciates legacy and compatibility. The world is better off because Dave Cutler went to Microsoft and built NT for a much larger market.”
Always striving for quality.
The best engineers like Dave are fanatical about quality. That means they write a lot of test code. They ensure that the code they write works. That’s what they hang their pride and reputation on. Most software engineers measure their success in terms of volume of code. The greats like Dave measure themselves in terms of quality of code – small amounts of quality, tuned, performant, robust code that doesn’t crash … It’s that fanatical embodiment of code quality that separates Dave from the rest. He just won’t accept anything less, from himself or others.”