Michael Doornbos
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A like costs nothing and means about that much. It’s the easiest way to tell someone you saw them without actually seeing them. 
 Write the letter. Make the call. Show up. 

It's Yippee Ki Yay o'clock somewhere
According to Hobby Lobby, Christmas is around the corner. The last few years we’ve surprised Julie with ugly Christmas sweaters. Last year’s will be hard to top. The search begins… 

Designing an open-toolchain FPGA dev board
I’ve always wanted an open-toolchain FPGA development board with at least 40 5V-tolerant I/O pins. 
 Since I’ve been on a PCB design kick lately (I did 3 boards in June), I decided to design one. 

Pro tip
Surround yourself with hopeful, imaginative people who are always learning and growing.
A web interface for my Siglent oscilloscope
The software for my Siglent oscilloscope runs on Windows, and I want to use it on Linux/Mac, so I wrote a web server interface for it and am serving it on my Tailscale network. 

First Principles
Getting 5 test PCBs made. Maybe it'll even work the first time...
Always building
There’s almost always something half-wired on the bench. 
 
 Some of it works. Some of it doesn’t yet. The pile of wire clippings means I’m getting somewhere. 
 I’d rather have a bench that looks like this than one that’s clean.
Matrix Math on a Commodore 64
The SID Chip Is a Reservoir Computer
Stop vibing and ship already

 READY.
The best office upgrade I've made in 2026
This speaker is the best upgrade I’ve made to my office in 2026. 

Seven years into the AGC rabbit hole

				 
				 
			 

 Somewhere around episode 8 of Curious Marc’s (and Mike’s) Apollo Guidance Computer series, like seven years ago, I decided to try to understand the system better. I’ve been writing code to implement the internals (Block II), with help from Frank O’Brien’s book and a ton of work by…
Second time through the AGC book
I love pretty much every pre-1990 computer ever made. But my favorite by a long shot is the Apollo Guidance Computer. This is my second time through this book. 

Rent the Builder, Own the Tool
What Happens When AI Gets Expensive
Wozmon, Eight CPUs, and a Paper Tape
Put Grok inside a HAL 9000 already
I’m genuinely surprised that Elon hasn’t made a Grok device that fits inside a HAL 9000 replica. This is one of my favorite things on my shelf, and you can easily fit an ESP32 with a speaker and microphone in it. 
 HAL/Grok would be SOOO much cooler than Alexa. 

Sunday afternoon Royals game project: a virtual keyboard for VICE
I’ve often wanted a virtual keyboard for the C64 and VIC-20 in VICE, so I spent some time learning the source layout and made one. It’s selectable from the menu. 
 The PETSCII layout still needs some work, but it’s coming along. 
 My GTK UI in C was a little rusty, but I eventually got the hang of it. 
 

Here's a class I wish I had actually paid closer attention to. No time like the present.
Fixing a Timex Sinclair 2068 and Porting the Bond Maze
Oh lord, what have I done. Prayers are probably in order.
This Blows My Mind
Looking at an ML workhorse for my home lab from System76, and the memory pricing stopped me cold. 
 
 192 GB of DDR5 for $2,644 over the base config. You can buy that same kit retail for a fraction of it. I get that integrators charge for validation, warranty, and the privilege of one throat to choke. That’s fair. But this isn’t a markup, it’s a different planet.
Biological Processing Units and a Commodore 64
Keeping the 80s Vibes Alive
I’ve been a Casio F-91W fan since high school. It’s too small to look good on my wrist (I’m 6'3"), so I use it on a little stand as a desk clock. Gotta keep those 80s vibes alive. 

Maybe AI Isn't the Next Big Thing, and That's Good News
I Wish I Had Your Problems
When things are bad, everyone wants to listen. 
 Lose your job, and people check in. Go through a divorce, and the meals show up. Get a scary diagnosis, and suddenly everyone has time for coffee. We’re built for that. We know how to show up when someone is low. We’re encouraged to share our struggles, to be vulnerable, to ask for help. There are entire industries built around it.…
Index of Coincidence: Modern Computer Update
Update to my Index of Coincidence “Modern Computer” testing with some other languages. 
 I brute-forced Enigma rotor settings in C, Rust, Swift, and Metal on an M4. 
 Single-threaded, Rust and Swift both land within 6-9% of C when you disable bounds checking. Leave the safety on, and there’s a real performance gap. Turns out billions of array lookups add up. 
 
…
Made a WordPerfect for DOS Typora Theme
Made a WordPerfect for DOS Typora theme. 
 IBM VGA fonts, yummy. 
 I know, I’m weird. 

SSH Is the Most Underrated Platform in Tech
It's an @8BitShowAndTell kinda morning
I wrote an iPhone calculator app
Over Christmas, I spent a lot of time with my beloved (and quirky) HP-16C. I decided I wanted to take it everywhere, but doing a phone calculator app seemed daunting. I’ve been plugging away at it for 3 months now as one of my many side projects. 
 I’m ready to call it a usable version 1.0. I’m sure there are bugs, but I’ll work those out as I use it more.
Artemis II Launches Tomorrow, and I Finally Feel Something (no, I don’t)
Breaking Enigma with Index of Coincidence on a Commodore 64
Writing Code Was Never the Job
I wrote a book
A novel. My third. 
 
 The first one was about five years ago. It has every problem you’d expect from someone who’d never written fiction. Flat dialogue, scenes that wander, characters that exist to serve the plot instead of the other way around. The bones are good, though. There’s a real story in there. I just didn’t know how to tell it yet. 
 The second was last November. Twenty-nine…
My wife found this for me and gave it to me for my birthday. I still know every word.
You've Got a Professional Kitchen and Unlimited Prep Cooks. Are You Going to Make Something?
The Best AI Integration Is a Folder
Make homebuilt computers great again.
Project Hail Mary Review
Andy Weir wrote two of my favorite books. I read Project Hail Mary when it came out, and then again about six months ago. I’ve seen The Martian probably eight or nine times. I’ve read that book three times. I could watch it again today. The movie, while different from the book, is an excellent adaptation. 
 I just walked out of Project Hail Mary, and I don’t feel like I need…
The Wallis Product for Pi Day
Every once in a while, people surprise me with the coolest things. A friend is now using a Commodore to read my writing. Awesomesauce!
Everyone has a kitchen now
On life
We got married young by today’s standards (20 and 22) and had our youngest child when she was barely 21. 
 Up until we knew we were right for each other in the “rest of our lives way”, she had loose, somewhat ambiguous career ambitions. Mostly out of necessity. But even before we got married, she was sure she wanted to be a full-time Mom. 
 This required us to start…
My custom Obsidian plugin
I’ve been using Obsidian for years now (recovering 10+ year Evernote user). I needed a simple way to log events, so I made a simple plugin for myself. Obsidian makes it so easy to get it to work exactly how I need. 
 And the bonus is that everything is a text file. This gives it the “forever” permanence that other tools can’t or won’t.