I’m a big fan of unit tests. Really. Big fan. Super big. Massive. Like, “make unit tests great again” massive. That.

So when I was working on my FB project (https://cgsql.dev) of course I invested in a lot of tests. In fact there is about as much test code as there is code code. And I wouldn’t have it any other way. That stuff saves my life on a daily basis because when you’re working on any code, but maybe especially on a compiler, it’s really easy to hork things up. So the code has 100% line coverage and lots…

I thought I would write some notes on some old “networking” tech that I worked on in the early 80s. I have “networking” in quotes because it isn’t really like what you would call a modern network, this was more about sharing particular devices but in some sense the things we’re going to talk about are “switches”. This is the Microshare line of products. I’m doing this all from memory so there’s some chance I have some of the details wrong but I’m confident this is substantially correct.

The general need here was to be able to share Commodore peripherals…

This is obviously an opinion piece and a bit of nostalgia but, despite that, Win95 being the most important OS ever is not a claim that I make lightly. I’m a student of this space and there are many great contenders but, in my opinion, none had as dramatic an effect on the entire industry, and certainly none as quickly as Win95.

So, what am I talking about? Let’s set some context:

1. In 1995, PCs outnumbered all other computers at roughly 80M units, growing to roughly 90M by 1998. I think a case can be made that this out numbers…

So the usual caveats apply: In the interest of brevity, what I’m going to write is only approximately correct, so do take this all with a grain of salt.

So here I’m talking about Fail-fast in the context of coding, not experimentation. This is the idea that there are many cases where your program should just abort rather than trying to recover. Classic examples of this sort of thing include “exit() or abort() on out of memory” or “out of disk space”. That sort of thing.

People are often surprised by this approach, having been trained to (e.g.) guard every…

I wrote this because my friend Laura did some tweets on “SCM” [Source Control Manager, “scum”] and it turned into a little bit of history of the late 80s and early/mid 90s.

Near as I can tell SCM went nowhere. I learned what I did about it from a series of demos that we were given back when I worked in languages at MS. It was totally unlike SLM (“Slime”, or for SLM 1.5, “Slime and a half”). Let me say a few things about SLM first.

• SLM works with just files, so you can stand up a repo in…

I’ve heard people say things like they want to create a “performance first” organization but frankly I think starting from those words is already wrong. There are many success factors in software systems, performance is one of them, but you can’t win by prioritizing just performance — you need all the other factors to be there as well. One of my favorite quips is “It’s easy to make it fast if it doesn’t have to work” which is my goofy way of saying “Dude, clearly just perf isn’t enough” or “You don’t get points for speed if it sucks” or…

[This is a dusted off article from 8/31/2007 which I didn’t want to lose so I’m moving it to Medium where it will hopefully stay alive. The original was on my MSDN blog. It’s the same article with some light corrections]

Introduction and Disclaimer

Regular readers of my blog are already familiar with my goal to provide brief and useful information that is approximately correct and that illustrates some key truths. Most of the time my articles are not authoritative and that is especially true in this case. I am certainly not an Official Microsoft Authority on databases and data…

Getting the very best results is rarely as economical as we might wish. Productivity is an important concern, and there are often trade-offs to be had. With regard to engineering effort, there’s pretty good thinking on this generally and when I taught classes in this I used a system like this one:

For every “feature” you’re building think about what letter grade it needs to get with rough definitions like these…

• A+ — the best the hardware is capable of, no compromises, “maximum effort” (you can almost never afford this)
• Fuzzy stuff in between
• D — if it was any…