The Importance of Constraints

The story of Unix’s almost legendary creation goes like this: In 1969, Ken Thompson, an engineer at Bell Labs, decided to write his own operating system. He accomplished this in just over a month while his wife, Bonnie, and infant son, Corey, were visiting family in San Diego. He dedicated one week each to writing the kernel (the core of the operating system), the shell (used to read and run commands), an editor, and an assembler (a program to convert source code into machine code). All of this was written in PDP-7 assembly language. You could read more at The Linux Information Project

Unix is still widely considered one of the best operating systems ever created, serving as the foundation for many other, both proprietary and open-source Operating Systems. What’s deserves our attention thought about its creation, are the constraints Thompson faced and how they co-shaped its success.

First, there was the time constraint: it had to be done in a month, requiring the completion of a major OS component each week. It should be done by a “team of one” instead of a dedicated team of engineers so it should be simple. Then there was the hardware constraint: the less capable, but available, PDP-7. With only 4KB of memory, the OS had to be small, which later became one of its strengths.

More than just serendipity, as Thompson believes that is responsible for UNIX success, constraints seem to play an indirect but decisive role - can be seen as the banks that guide and direct the flow of water, enabling it to travel further. They force focus and creative solutions.

These thoughts were sparked by the DeepSeek R1 and v3 announcements. The hardware resource limitations faced by Chinese firms due to the ban on advanced AI chips led DeepSeek to pursue a seemingly more optimized and radical approach to building its models. This, in turn, resulted in significantly lower costs for comparable performance. While details of how this impressive achievement was accomplished are still emerging, it’s an interesting example of how barriers can force a new way of reframing and solving a problem, sometimes leading to novel solutions.