Laszlo Hanyecz, one of Bitcoin's early developers, clarifies the answer to the old riddle: What operating system did Satoshi use to build Bitcoin? Most people know Hanich as the "buyer of pizza with 10,000 bitcoins", but that has led to his role as a primary developer of bitcoin being overlooked. In fact, Hanich was the one who made Bitcoin compatible with Mac's operating system, because Satoshi didn't have Mac and didn't know how to develop Apple's operating system.
Most people know Laszlo Hanyecz as the "buyer of pizza with 10,000 bitcoins", but that has led to his role as an early bitcoin developer being ignored. Hanich was the one who added support for MacOS to the original Bitcoin client and even invented mining GPUs. Hanich entered the Bitcoin space in early 2010 and worked with Satoshi Nakamoto for about a year. Their job was mostly to fix various bugs, but later changed to Apple's compatibility with Bitcoin: Satoshi didn't have a Mac and didn't know how to develop Apple's operating system. Laszlo stated:

At first, Bitcoin didn't work on the Mac. So I transferred it to the Mac. And in fact, Satoshi asked me to work on MacOS versions. I did it because he didn't have a Mac. So it was my binaries that were posted.

Satoshi used Windows
Satoshi developed Bitcoin using the Windows PC. This may be an unusual choice for someone who cares about information security and privacy, as Linux is inherently built for these purposes. This may also support the idea that Satoshi was not a professional coder. These details in the selection of the operating system add another small piece to the large Satoshi identity puzzle. Perhaps the cryptographic community can collect smaller pieces of a complete picture separately.