Reports that Microsoft has rolled its own “Linux distribution” have provoked the kind of disbelief normally reserved for curly-tailed livestock sprouting wings.

But the reality is, despite former CEO Steve Ballmer famously describing Linux as ‘a cancer’, that Microsoft is more than willing to accommodate the open-source OS when it can see a benefit.

For a number of years, Microsoft was among the biggest contributors to the Linux kernel and today about one in five of the operating systems running on Microsoft’s Azure cloud platform are Linux-based.

In part, Microsoft’s change of heart has been driven by its customers, as developers and enterprises make increasing use of open source software. The Linux distro Ubuntu is overwhelmingly the most popular OS on Amazon’s Elastic Compute Cloud – so it only makes sense that it is also available on Azure.

In light of this pragmatic acceptance of open source by Microsoft of late, it’s perhaps less of a surprise that it was willing to make a Linux-based OS for datacenter networking, particularly when that software bears little resemblance to what the average user understands as an operating system.

To some extent Microsoft has always been open to experimentation. Go back a generation and Microsoft was pretty cosy with the Unix operating system that helped spawn Linux, with Microsoft licensing its own version of Unix called Xenix for several years in the 1980s.

But beyond just Linux, Microsoft seems to be becoming more willing to dabble with open source in general.

The firm has open sourced large parts of its .NET development framework, hitched Windows to the popular open-source container automation platform Docker, and even hinted it may one day lift the lid on the code that powers Windows.

This openness to openness isn’t necessarily born out of any newfound affinity for free software at Microsoft – at least not on a company-wide level. Microsoft will still commission reports that cast open-source rivals in a negative light compared to its own products, as seen recently in Munich in Germany and Pesaro in Italy.

Instead there are many practical reasons a large vendor like Microsoft might seek to use open source technologies, as outlined in a research paper, Beware of Geeks Bearing Gifts by CSC’s Leading Edge Forum. These can include removing barriers to entry into an opponent’s market, encouraging standardization around that vendor’s practices and developing ecosystems that strengthen their position.

So while it might be a bit hard to swallow the proclamation by current Microsoft chief Satya Nadella that “Microsoft loves Linux“, the company certainly is willing to exploit open source software when useful.