Great Pods
Dave Plummer: Programming, Autism, and Old-School Microsoft Stories | Lex Fridman Podcast #479

Key Points

Dave Plummer is a legendary Microsoft engineer who created Windows Task Manager, zip file support in Windows, and ported Space Cadet Pinball to Windows
He started programming on a TRS-80 Model 1 at age 11, riding his bike to Radio Shack to use their display computer
He dropped out of high school but later returned, finished, and went to university after working at 7-Eleven
Task Manager was originally just 87KB in size and was designed to be extremely reliable and responsive
He worked on MS-DOS, Windows 95, and Windows NT, porting the Windows 95 shell to NT
Windows activation was implemented by him late in Windows XP's development cycle
He has autism and describes monotropism as the fundamental theory - intense focus on one thing at a time
Masking (acting neurotypical in social situations) requires significant effort for people with autism
The 640KB memory limitation in MS-DOS meant every kilobyte used by the OS was unavailable to users
He learned multiple assembly languages (x86, MIPS, Alpha, PowerPC) because debugging was done entirely in assembly
He created Hyperache, a file system cache for Amiga, to pay his way through college
The Windows blue screen of death colors were chosen simply because they matched the developer's editor color scheme
He reverse-engineered the Atari Tempest game and is building an AI using reinforcement learning to beat his world record
His advice for autistic programmers: sell what you can do, not yourself - show your portfolio and actual work
He manages a GitHub project comparing performance of 100+ programming languages implementing the same prime number algorithm
Space Cadet Pinball physics differ slightly from the original because he draws frames as fast as possible instead of limiting to 30fps
He believes future programming will involve describing component interactions to AI rather than writing individual lines of code
His meaning of life: making complex things that are useful to other people while leveraging his creative abilities
Full Transcript

Language: en
The following is a conversation with
Dave Plameumber, programmer and an old
school Microsoft software engineer who
helped work on Windows 95, NT, and XP,
building a lot of incredible tools, some
of which have been continuously used by
hundreds of millions of people like the
famed Windows Task Manager. Yes, the
Windows Task Manager. and the zip unzip
compression support in Windows and he
ported the code for space cadet pinball
aka 3D pinball to Windows today. He's
loved by many programmers and engineers
for his amazing YouTube channel called
Dave's Garage that you should definitely
go check out. Also, he wrote a book on
autism and about his life story called
Secrets of the Autistic Millionaire
where he gives really interesting
insights about how to navigate
relationships, career, and day-to-day
life with autism. All this taken
together, this was a super fun
conversation about the history and
future of programming, computing,
technology, and just building cool stuff
in the proverbial garage.
This is the Lex Freedman podcast. To
support it, please check out our
sponsors in the description. And now,
dear friends, here's Dave Plameumber.
Tell me about your first computer. Do
you remember?
I do. I didn't own my first computer for
a long time, but the first computer I
ever used was a TRS80 model one level
one 4K machine. And I rode my bike in
fifth or sixth grade, so I was about 11
to the local Radio Shack. And you know,
they had a standard component, stereo
systems, and everything else Radio Shack
had, but they had a stack of boxes that
was labeled computer. And so I was
asking the people that worked there
about it. They So they just got it and
they hadn't set it up yet. And so I was
rather precocious and I figured, well,
I'll set it up for you. And they said,
"Okay, have a shot." Did you know what
you were doing?
Absolutely not. I mean, it's no worse
than a component stereo. The only thing
is that Tandy and their infinite wisdom
use the same five pin connector for
power, video, and I think cassette. So
they're all identical, and if you plug
them in wrong, you'd blow it up. So I
read the label and uh got it working and
wound up playing with it and not knowing
anything about computers. So I'm typing
English commands into it and you know
print 2 plus2 works perfectly yet more
simple English that you enter into a
basic level one interpreter is not going
to get you very far.
So you're trying to talk to it in
Yeah. Didn't know any better. And I
still have an old full scap that I wrote
in sixth grade of a of a program that's
kind of logically correct, but has no
chance of working on any interpreter
that existed at the time. So it took me
a while to figure out what was actually
going on with them. But I rode my bike
down there every Thursday and Saturday
and they had graciously let me use the
machines. When was this?
Okay. What was the state-of-the-art of
computing back then? So what are we
talking about?
Well, the big three had come out. There
was a the TRS80 model 1. There was the
PET 2001 and the Apple 2 came out
roughly simultaneously.
Apple 2. Would you say that's the
greatest computer ever built?
Probably in retrospect. Well, I would
probably give that to the Commodore 64.
Yeah, you and I agree on this. That was
my first computer probably many years
after it was released. But yeah,
Commodore 64 is incredible. But yes,
Apple 2 had a huge impact on the history
of personal computers,
right? It's hard to gauge the long-term
impact, but I think the 64 itself
probably influenced more people. So,
that's my reason for picking that one.
You think so?
The sales are certainly higher.
So, Commodore 64 sold a lot.
Yeah. I mean, the numbers are hard to
believe. It depends which numbers you
believe, but even the medium estimates
are pretty high.
All right, cool. So, you eventually
graduated to the Commodore 64. Uh, like
tell me about that machine. What did you
do on the the Commodore 64? Well, the
first thing I did was overheat the
floppy drive on it, which was
unfortunate because it wasn't a warranty
machine. We had my parents didn't have a
lot of money, so we bought it from
Computer House as opposed to one of the
major retailers, which meant when it
died, it had to go back to Germany or
something to be fixed. So, I was left
with no floppy and so I had a cassette
deck, which was the best you could do at
the time. And so, I was writing small
things and I had a machine language
monitor that you could load from
cassette. Didn't have an assembler built
in, but had a disassembler. So, you
could enter the op codes in 6502 in hex.
And if you were careful about planning,
you'd be able to write some basic
programs. So that's kind of how I
learned. And uh the first thing I ever
wrote on it was a clone of Galaga. Now,
it's a bad clone of Galaga, but it has
the major enemies that attack over time.
And it's all written in handcoded
machine language, and you can't relocate
6502. So if you need to add code in the
middle, you need to manually sort of
jump to somewhere else, do your work,
jump back to where you were. It's just
hideous spaghetti code. But it all
worked eventually. and I went to make a
backup of it to preserve it for future
scholars or whatever the hell I was
doing. And uh I copied my blank floppy
onto my data floppy. So that was my
first experience with data management.
And so I don't have a copy of my first
program anymore.
What was that feeling like? Do you
remember of of uh just doing something
um if I may say so like stupid, you
know, which is a part of the programming
experience.
Yeah. There was a huge amount of guilt
cuz right you destroy several weeks of
work and you know it was because you
rushed or you did something stupid or
you made a
unwise choice.
What can you tell me about the
programming involved in that?
So it's literally machine language.
So machine so it's not even not assembly
yet because there was no assembler built
in. So I should have wrote an assembler
written an assembler as my first task
but I wasn't that clever. So
how hard is that to do?
Trivial and it's just one of those
things that sticks. I think you do it so
many times. You know, if I give you a C
issue, there are certain syntactic
issues in C that you're never going to
forget and get wrong.
And it's just one of those like
what are then the limitations of
programming in machine code as a
programmer?
The biggest issue is you have to write
completely sequentially because at least
in that variant 6502, you can't add
things later. You can only add things on
the end. So it's like programming a tape
in a way.
What was the most complicated thing
you've built with machine language?
uh that game would be I mean in assembly
language I've done a fair bit of
complicated stuff but in actual machine
language I think that game would be the
only thing I've actually
I literally built a game
not a great game but it worked.
Okay. All right. And then you erased it.
I did.
All right. When did you first fall in
love with programming? When you figured
out like this is a this is something
I think there was two stages for me. I
always knew immediately that I was
fascinated with these machines. from the
TRS80 Model 1. It's all I wanted to do
is ride my bike back there and have more
time with it. And I did that, you know,
to wear out my welcome as much as I
could. And the other revelation came, I
think, about second or third year
university when I realized I love
programming, but I have no idea what I'm
going to do. Am I going to make the 12
flash on a VCR somewhere, or am I going
to go work on an operating system? I
have absolutely no idea what I'm going
to do postgraduation,
but I love what I do. And so, I think
that was a lot of consolation. And it's
like it doesn't really matter what I'm
doing at this point cuz I kind of love
doing it. So
So you'll figure it out.
As long as you're following this kind of
feeling that's
I knew I was in the right area finally.
All right. You dropped out of high
Yeah. Not the smartest move.
Okay. But you ended up going back to
school and being very successful at
school and just in general successful as
a programmer, as a developer, as a
creator of software. Uh how were you
able to find your way? Can you tell that
journey of dropping out and then finding
your way back?
There's no moment when I dropped out.
You just go less and less and less until
you realize it's going to be
embarrassing if I show up cuz I haven't
been there in a long time. And then
pretty soon you're just not going. And
that's how you drop out of high school.
So if you find yourself on that path,
stop doing that. Um, but that's
precisely what I did. And so now I'm not
at school and I have to get a job. So
I'm working at 7-Eleven and a paint
warehouse and stuff like that. And
7-Eleven is actually kind of an
interesting job because it's a job I
think they keep rotating for people that
are smart enough to do the night shift
with all the accounting and the
administration and stuff they make the
night shift do but that have reasons
personally that they need to work at
7-Eleven. Um, and I was one of those
people cuz I had no high school diploma.
What are some memorable moments from
that time at 7-Eleven? Uh, maybe what do
you uh appreciate about the difficulty
of that job? Probably the worst moment
for me. I mean, I got held up at knife
point and stuff and that's all
entertaining, but the worst the most
this the suckiest part for me was doing
the gas dips where you've got a long
it's like a 15 or 20 foot wooden stick
and it's measured in gradients of inches
and feet and you drop it into the
gasoline tanks and then you bring it up
and you measure where the gasoline sits
because there's no electronic sensor.
So, I'm doing that and the first time I
do it, I drop the pole and I regrab it.
Well, that's about a thousand splinters
of wood into your hands and it's 40
below out and that really sucked.
Oh, wow.
Um, I realized I don't want to do this
for my whole life. I knew that. So,
okay. So, you stand there frozen with
splinters in your hand.
And at some point I have a revelation
about my life that next time I'm going
to do it differently. And then how
ludicrous that is hits me about 3
seconds later, right? And I think that
was really the moment for me where I
realized that I've got to do something
different. And so even though I was 21,
I went and I talked to the uh principal
of my local high school and I was like,
"Can you let me back in?" And he said,
"No, you're too old and we don't have
room." It was his main reason. And I
said, "Well, between now and then,
somebody's going to drop out, so you'll
have room. So let's assume you have
room. Can I come back?" And he was
gracious and let me come back. And so I
did the three or four classes that I
Yeah. You know, just if you can linger
on that, the slow dropping out, that's a
weird thing that you can do with your
brain. You realize to yourself that you
don't have to do the thing that
everybody else is doing. And that's a
dangerous realization because like you
kind of have to to be part of society to
do certain things,
And if you realize like you don't have
to do what everybody else is doing, uh
you can either have an incredible life
or a really difficult life. Well, the
problem with that process is you're
making a much smaller decision. I'm just
not going to go to class today. Yeah.
And that's all you're deciding. But you
do that enough times, you're making a
much bigger decision,
and that's the problem.
So, it's better to make if you want to
live life in a non-standard way, it's
better to make the big decision
explicitly and then you can stop going.
Don't allow yourself to make the the
It'll be made for you eventually.
Okay. you well you got back and you
eventually went to college and were very
successful as a student and you weren't
that good of a student before.
No, I was a terrible student in high
school and even my first semester of
college I still wasn't taking it quite
serious because I got mercy passed in
geometry 90 which is like the makeup
class for the geometry 12th grade class
that I didn't have and that scared me
because I realized by 1% or the grace of
the prof professor that let me through I
just about ended my entire university
career here. So fortunately those marks
don't count on your transcript cuz
they're remedial classes and so I got
kind of a fresh start the next semester
and did it for real and I did it for me
and that made all the difference.
What can you speak to maybe by way of
advice on how to be successful as a
Well ideally there's some aspect of
school that you do enjoy whether it's
arts, whether it's computer science,
whether it's shop class, whatever. So go
for those classes and just put up with
and do the hard stuff because it's way
easier than having to do it later. And
that's easy to say when you're 50some.
It's harder to say when you're 15
something. But
it makes a lot of sense.
All right. What's the story of you
joining Microsoft? How do we get to
there from 7-Eleven
to Microsoft?
Yeah, it's a big jump. So, I had uh gone
back to school and I think it was in my
third year of university. I was working
for the phone company for the summer as
a summer job and I'm doing conversions
of their Ubet to TCP IP and modern
networking which really amounts to
swapping cards but then figuring out why
their config. This doesn't allow Lotus
to run anymore cuz it's got 10K less
than it used to. And it's just a
horrible time to be working in
computers, but I was doing it. And at
lunch, I'm sitting in the food court
with the old and the board. And I'm
reading a book that I had bought called
uh Microsoft or Bill Gates in the making
of Microsoft Hard Drive, I think is the
title. And it's a great book. It's just
sort of a matterof fact history of how
Microsoft came to be, what it's like,
how it operates, what the people are
like there. And I'm reading this book
and I become really entranced by it and
fascinated because it sounds like
exactly the place that I want to be, but
I'm in Saskatchewan. So, what am I going
to do about it? And what I wound up
doing was I had put myself through
school with a program called Hyperache,
which is a file system cache for the
AmIGGA because didn't have any out of
the box. And it had done reasonably
well. And so I went through my
registration cards because in those days
you had a 4x6 card that people had to
fill out with their name and their
address and if they had an email, their
email and they send it in, they get
notifications of updates and so on when
it's shareware. And I went through the
whole stack looking for anybody with a
Microsoft email address and I found
maybe three or four people and I just
cold emailed them and said, "Hey, I'm a
operating system student in Saskatchewan
looking for an opportunity." I don't
remember exactly what I said, but one
guy, Alistister, Alistister Banks, he
wrote back and he said, "I know somebody
that I can put you in contact with." And
he put me in contact, I think, with a
guy named Ben Slifka who did a phone
interview who eventually want to hire me
to work in MS DOS for the summer. So,
that's how I got there.
You put yourself through school by tell
me about Hyperache. You build a piece of
software. It's the weight loss program
for hard drives.
That was sufficiently useful to a large
number of people that would somehow give
you money.
Yeah, it made decent money. I mean, I
sold a couple thousand copies, 20 bucks
a copy or 40 bucks a copy.
What program? What language was it
written in?
So, there was some assembler. The actual
really tight code to do the real work of
transferring data to and from the cache
was 68,000 assembly. Everything else was
Okay. This is uh like file system IO
device block IO. So any block that gets
serviceed from the drive would go
through my cache first and it was an
Nway associative cache and so it would
try to match the geometry of the drive
and do prefetch based on you trying to
read a whole track at one time that kind
of thing.
What what was it like
trying to get your software out there at
that time? Like where how were you able
to find customers?
Yeah, it's interesting. I think I
started on Usenet and some of the AmIGGA
forums posted here's my trial version
try it out for 30 days see what you like
and eventually got picked up by a few
retailers and I remember I was with my
now wife in her car and she had a cell
phone cuz her dad was very concerned
about her safety and so this is late '8s
and she's got you know the antenna on
the roof and the big box in the trunk
the whole deal but we got a call from
one of the uh software retailers that
wanted to buy 50 copies at 20 bucks
which to me is a thousand bucks which in
1989 or whatever year it was was a big
deal and so eventually a number of
companies just bought inventory.
Let's go to that time. It's such an
interesting time with Bill Gates and
Microsoft. Why do you think Microsoft
was dominating the software and the
personal computing space at that time
and and really for many many many years
at the time it was the single most
potent assemblage of smart people that
I've ever been a part of and I've been
in academia and I've been in industry to
a certain extent and
you know that when you're working at a
regular computer company the one guy who
actually knows what he's doing his
smarter friend he probably works at
Microsoft so when you get there you're
the big cheese from your small town you
think you know a lot and all of a sudden
you're just in an environment where like
uhoh I'm just not going to speak cuz I
don't want to look stupid.
Okay. Uh what are what about Bill Gates
himself? What are some qualities of Bill
Gates that you think contribute to the
success of Microsoft?
I think he was relentless in the pursuit
of his one dream which was his old
slogan of a computer in every home and a
computer in every desk. It was his
special interest and he was a smart guy,
super determined and he hired people
that were as smart or smarter than him
to help him execute it and he built an
almost unstoppable machine of intellect
to go forth and make
let's say very simple products. MS DOS
is not a complicated product by any
stretch but it's exactly what the market
needed at that time.
Yeah. I mean, Emma's DOSs changed the
game and uh that's actually the team you
joined, the MS DOS team and I think you
joined before Windows 95 was released.
Uh so tell me about the story of MS
DOSs. It's uh success of MS DOSS was
probably pivotal to the success of
Microsoft.
Yeah. Before DOSS, they were largely a
language company. So they had made basic
for a lot of computers and they had a 4R
compiler and a Pascal compiler, that
kind of thing. But their deal to have MS
DOS included with every version or every
instance of the PC effectively set them
as a standard that they were able to
leverage for decades going forward and
to a certain extent they locked into
that and on the other hand they were
smart to have done it. So because they
didn't charge IBM a lot of money for it
but making it a standard
really played out to their advantage
over time.
Uh so at that time MS DOS no graphical
interface. Can you just speak to what
the heck MS DOS is?
It's largely a command launcher. So you
type in a name of a command, it looks up
to see if that's in the current
directory or on a special path of
folders and it loads it into memory and
executes it if it's there. And that's
90% of what MS DOS does. Now it has
environment variables and some
complexity and a small scripting
language built in, but it is basically
just an operating system shell that
allows you to uh use the resources of
the computer like the hard drive or the
CPU. And it doesn't allow you to
multitask. There's no graphical
interface. Now, Microsoft did add a
textbased graphical interface for things
like an editor and quick basic in DOS 5,
I believe, and it was a DOS shell, which
was sort of a graphical file manager in
MS DOS 4. So, they experimented with it,
but it's largely a command prompt.
Did does it have ability to communicate
with uh external devices, so drivers and
all that kind of stuff? Like how
expansive of an operating system was MS
DOS? Well, it was limited by the
original x86 instruction set which
limited it to 640k and then there were
various band-aids on top of that to do
high mem and then extended memory beyond
that and uh a lot of hoops have to be
jumped through to make anything work
without consuming base RAM.
Yeah. I mean you so you programmed on MS
DOS. What what's it like? What are some
interesting details there? Like you said
there's the memory constraints of 640 uh
kilobytes.
Yeah. Now 640k is the maximum that's
ever going to be available. So it's not
what's available to you as an operating
system developer because whatever you
use is what the user won't get. So if
you use 10K needlessly, you're going to
every machine in the world now has 10K
less. So it's kind of a big
responsibility.
Is that a true quote from Bill Gates
where he said
nobody will ever need more than 640K.
Yeah, I know it's not him.
It's been attributed to him but not
Uh okay. Okay. So, I mean, what are some
interesting aspects of you that you were
able to do as an intern and when you
joined on MS DOS and beyond?
One of the first things I did was to
take Smart Drive, the disc cache, cuz I
had familiarity with disc caches and to
add CDROM caching to it cuz I was new.
CDROMs were just just coming out.
Microsoft Bookshelf is one of the few
products you could run for it. And as
you can imagine, caching a CD speeds it
up by dozens of times if you're smart
about it. So, it it was a big
performance win and a nice thing to work
on. Um, a bigger part of that was moving
a bunch of smart drive and eventually
the double space compression engine up
into what's known as high memory.
And without rat holeing on the technical
aspect of it on the x86, there's
something I believe called the A20 line.
And I probably have this backwards or I
got a 50-50 shot at it, but if you've
got the A20 line asserted, then your
memory pointers wrap at the 1 megabyte
And if not, they don't. So you continue
going up in memory. So you can rewrite
memory above by combining your segment
and offset registers to a number bigger
than 1 megabyte and you get an extra 64k
and you put your code in there and then
you just put stubs to jump to it from
low memory and so you can get another
64k out of the machine that way. And we
did that for a couple of the products
and that's I had no idea what highm was
cuz I was an Omega programmer and I had
never written any x86 code before I got
there. So
So that was like a cool optimization
that you got to be a part of.
So what about Windows? There was a
parallel development of Windows 95 right
at that time. Did you get did you get a
chance to interact with those folks?
I actually worked on Windows 95 for
about three or four months. I was on the
comm team doing the presentation cache
which is when you insert a say a word or
an Excel spreadsheet or chart into a
word document. You don't want Excel to
have to be loaded to render it every
time. So there's a presentation cache of
enhanced metaphiles. And I was working
on that. So that shipped in Windows 95,
but I moved to the shell team about 6
months after getting to Microsoft. And
so I worked on NT from there forward.
Okay. And what's 95? What's NT?
Uh Windows 95 is an evolution of the
original 16-bit Windows 3.1, which was
the very first popular version of
Windows. And it adds 32-bit support and
VXD drivers and a bunch of new
technology and an entirely new user
interface. And it's something that at
the time was revolutionary. People lined
up at night to uh wait in line to buy
the thing. Can you just take us back to
that time and describe why 95 was such a
big leap from 3.1? So, Apple already had
a graphical interface. Uh, Windows 3.1
had a graphical interface. Why was
Windows 95 such a gigantic leap?
I don't want to make it as basic as the
start menu, but I think it's a big part
of it. I know when I first saw it,
I couldn't quantify what about it was
different and awesome, but I realized
that I wanted to be a part of it. And
that's why I started writing a shell
extension which became uh zip folders at
some point. But
I was just fascinated by the new shell
and that's why I end up working on the
team that brought that shell over to the
NT and what's Windows today.
Would you say that's the greatest
operating system ever? What's the most
impactful operating system ever?
Windows 95 would be number two for me. I
think OS 360 is going to be number one.
Okay, interesting.
Did you take a machine and write a
Cobalt program for it in 1962? jump in
your time machine, go to Pikipsy and
boot up an IBM Z17 mainframe and run it
today. And they've been doing it for
however many years that is. And it's all
in the business side. So we as consumers
don't have much access to it, but I
think it was probably as influential in
the commercial side as Windows 95 was in
the home side. And then probably Linux
would be number three for me. I put
Linux as bigger than Unix, which doesn't
work because you can't have one without
the other. But the impact of Unix BSD
and so forth is largely in the academic
space. It's by programmers for
programmers. So yeah, Linux created
I mean it was the embodiment of the
open-source spirit
at its largest scale. All right. So it
almost created a community and it it it
created a spirit of programming that uh
propagates to this day. That's true.
That's true. Like scale matters. Yeah.
And it penetration on the server side of
things now is I don't know if it's
equivalent to what system 360 achieved
but it's almost ubiquitous. So
yeah the world I this is the quiet
secret of the universe as it runs on
Okay. So uh tell tell me about the days
uh your work days. What were they like
back then back uh back in the MS DOS
Windows 95 days? Take me through a
productive day. Well, your day starts
coming in and you got to download the
address book, which is Microsoft has
between 10 and 15,000 employees at this
point and we're all on MS Mail. We're
just getting off of the PDP11 called
Miss Piggy, which ran Whizmail. And uh
we're running MS Mail, but MS Mail has a
fixed address book that every user must
download every morning. And when there's
10,000 people downloading 10,000 people,
it gets pretty messy. And I think we're
on 10 megabit networking at the time. So
your first hour is downloading the
address book which was always
frustrating but you'd use that time to
look at the crashes that would have
happened overnight from a process we
called stress which is N&amp;T all the
machines that are unused run tests all
night long and they try to crash
themselves and if they manage to crash
themselves it will drop into a debugger
with a serial cable to another machine
and you can connect to that other
machine and remotely debug the crashed
machine. So you come in and they will
have triaged bugs. You know there was a
crash in the start menu so we'll assign
that to Dave. And so you come in and
that's your first thing is to connect
because you got to get that machine back
to the guy that owns it and unlock the
machine. So that's your first hour of
your day is basically triage for bugs
that have come up from stress overnight.
And then at that point it's probably
back to coding which unfortunately 80%
of the time is fixing bugs. Especially
in my career it was porting code and
fixing bugs. I wasn't writing a lot of
new code. There were exceptions. cuz I
wrote a lot of new code on the side to
get it out of my system
from a day dayto-day grind of always
fixing bugs in other people's code which
is amazing learning experience.
So you did a lot of the at Microsoft you
did a lot of the porting of uh what is
it Windows 95 code to NT.
Yeah we took the entire Windows 95 user
interface and we ported it to NT which
mean meant making it unicode for one
thing. So everything that was 8 bits is
now 16 bits. pointers. It's It's quite a
mess when you switch the code over as
you can imagine.
Can you give us insights in what is
involved in porting?
It's like breaking into somebody's house
and going through all their stuff and
seeing the stuff in their drawers that
they didn't want you to see.
You find all the good stuff, the pretty
pictures hanging on the wall, and you
find some disturbing stuff in the
nightstand. Uh I saw code that was like
200 some characters wide with you know
profanity and swears in it and it
eventually got all cleaned up over the
years by the time I left but it was not
always the most professional code in the
right cuz every single piece of code you
have to go through
line by line so you see it all.
Yeah. Yeah. I mean that's the that's the
story of programmers. You think you
write a piece of code and you think
it'll never it'll never be seen by
anybody. And sometimes often times that
code is going to be seen by a very large
number of people
that come after you including you 5
years later
you yourself looking at your own code.
Okay. So uh tell me about Windows NT
that was a giant league too.
It was it was basically a clean sheet
design. So they went and they got Dave
Cutler from Digital Equipment who had
done operating systems for them. VMS and
RSX11 he had done. And so he came over
after I believe it was Prism and Micah
were some projects at Deck West that got
cancelled and so you had a whole team of
guys with their project is canceled and
basically they took a whole bunch of
them and came to Microsoft and I don't
know the specific deal but they all
showed up. So you had Dave Cutler and
Mark Lakowski and all these really smart
guys from Deck and they did basically a
clean sheet but they also had OS2 as a
starting point but OS2 is of course
written in assembly language and NT is
going to be written in C. So to what
extent they were able to leverage any of
that I don't actually know but at least
they had a system to start with.
You said that Dave Coulter is the man
the mind behind Windows. Can you uh can
you explain?
So Dave Culler is the architect of the
kernel. So he is Lionus in the Linux
world. It's Dave C in the Windows world.
Dave C. Okay. And uh it's not that there
weren't other people that contributed,
of course, huge pieces to it, but uh I
think he's the driving force behind it
and always largely has been. And he's
still I think he's 85 now. He still
codes every day. He's a Microsoft
fellow. He's far as I know still goes
into work. So,
uh can you speak to the genius of that
guy? Like what's what's interesting
about his mind having having worked with
him, having interacted with Dave Culler?
Well, the dude's wicked smart, but he's
also like a farmer. He's like the guy
that will follow you around and make
sure that stuff gets done and gets done
right to make sure that you're not
checking any crap into his operating
system and he won't tolerate it. And
he's a real taskmaster in that regard.
But I think it really paid off because
it was a very big paradigm shift for
Microsoft developers to be subjected to
Dave Cutler digital equipment style of
leadership.
uh what did you learn from that about um
successful software teams where there's
large number of people collaborating cuz
Microsoft had a lot of brilliant
engineers back then and like you said D
cutler they had to uh they had to create
completely new systems many of which we
still use today what have you learned
about great software engineering teams
from that time
tools are everything I think for one I
mean people are everything we'll give
that as a granted but the tool set is a
huge factor. If we would have had git it
would have been immensely easier. We
were using diff and you know manual
deltas to do the porting and stuff. So
being able to fork a branch of source
code would be a luxury that is new to
me. So
at the time it would have been really
What were some memorable conversations
from that time when you walked over next
Uh well one I was not present for was
somebody was complaining. A new hire
came into the team and was working on
what I believe was called Cairo. And
Cairo was going to be the next future
operating system was going to be
beautiful and have a whole new user
interface newer than Windows 95. And it
never materialized. But while they were
working on it, one of the guys was
working on Cairo was kind of flaming on
the open anti-dev alias, which is
thousands of people, how shitty the anti
boot experience was. And the response
that came back was an epic flame that I
wish I would have saved. And I won't
name the guy who wrote it. He knows who
he is. But uh
it was a work of art of angry flame
mail. Kind of like the ones you see line
of send every now and then about colonel
stuff. So it's a very similar sentiment.
Were there like kind of intellectual
debates like there's some some heated
stuff engineers?
Yeah, it got contentious. So you've got
intellects competing and eventually the
technical merits for some people are
secondary and it's about besting the
other person in that argument and it's
no longer productive at that point half
the time. But there was a fair bit of
Yeah, I've I've seen those kind of
debates in uh like programming language
design communities like Guido Van
Rossom, the leaders of those
communities, it can wear them down cuz
people get you almost like forget the
mission you're on and start being very
nitpicky about the details. I mean,
engineering minds get together and you
just go to war over the stupidest like
syntax subtlety,
right? was I shouldn't say stupid but
it's a small syntax subtlety for that's
for programming language and I'm sure
there's internal battles about specific
kernel components.
Yeah, I mean there was one that I lost
that still bugs me to this day I think
and uh
I still think I was well when we were
doing the shell we were porting
everything from ancient unic code. So
every character that was 8 bits now
becomes 16 bits. Now, the problem is I'm
on a MYIPS box because I'm porting it to
risk and you can't have unaligned
addresses. But if you take two ID lists,
which are basically path components, you
take the one for C colon backslash, take
the one for Windows, take the one for
system 32, and you add them together.
But if you've got an odd number of
characters, now you're at an odd address
in this thing. And it takes me an
immense amount of work to turn on
exception handlers, to do unaligned bite
access, to pull the string out and copy
it manually. It's just a it's literally
like a hundred to a thousand times the
amount of work to read a string out of
this ID list on a MIP's machine because
it's unaligned. So I'm having the
argument that even though it's late in
the Windows 95, they've already shipped
one beta that we should now just
guarantee that ID lists are always an
even number of bytes or do some hack to
just make sure this never happens. So
the code that references them on other
hardware can just blaze through it. And
it became a shouting match and sort of a
personal match. And I lost that one. And
I still think that I know today that
that code running on Windows is
thousands of times slower than it has to
be and it nobody cares because it's
plenty fast but it could be a lot
Yeah. So uh yeah I mean you mentioned
MIPS and risk how deeply did you have to
understand the lowest level sort of the
lowest level of the software and even
the hardware with the stuff you were
building like what are the layers of the
abstractions you had to understand to be
successful with all the stuff you're
doing with NT and before that with MSTOS
well about half your day is going to be
spent debugging and h and most of that
time is going to be spent in call stacks
that are in pure assembly language cuz
there's No source level debugging.
So it's not like we're in Visual Studio
and you hit a break point and it pops up
and there's the source code. You can go
look at the source code, but you're
looking at the raw assembly dump from
the machine at all times.
Even if you're programming in C, the
debugging is in assembly.
Yeah, 100%.
Oh man.
So it's a little cumbersome.
Better yet, we're doing four instruction
sets because we're doing Intel, uh,
MIPS, Alpha, and Power PC. So depending
on which machine it crashes on, you've
got an entirely different instruction
set that registers.
So you get reasonably adapted debugging
all four, but uh I had more experience
in my so myip stuff would come my way.
That's a real endurance event. I mean
can you speak to that the the torture
there's debugging especially that kind
of debugging without the without the
tooling associated with it? I mean
that's you know programming
kids these days
uh programming isn't all about creating
beautiful things right it's uh also
fixing things
yeah I would say that 20% of my
professional life has been creating and
80% has been debugging and fixing
and I mean I got a bit of reputation as
somebody who could fix stuff and so
stuff like that would flow to me and so
I would spend more time doing that I
wasn't renowned as a creative UI genius
where I'm flowering ing all these new
ideas. So, I got to fix ugly stuff. But
you get really good at that. So, I don't
mind it until it's one of those things
where you've been chasing it for so long
that you don't know what to do next and
you can't understand why it doesn't work
or how it ever worked or whatever
situation you happen to be in. And uh
you know, after a day of it, it can get
pretty trying.
Yeah, debugging can be real torture.
This could be really really difficult.
There's a psychological component I
think of perseverance. I think the ones
that, you know, take you a day, they
resolve one of two ways. Either it's
like, oh, extra semicolon, and then you
finally see it, or it's some horrible
manifestation of crossthreaded
department nonsense that was really
hard. But it can go both ways.
Um, I had a bug, it wasn't my bug
actually, but it was a manifestation of
a bug in task manager where every now
and then it would say greater than 100%
total CPU usage. And this looks pretty
silly for a task manager. So, I had
tried to resolve it for a long time. And
I'd talk to the colonel guys about my
issue and they were unsympathetic, let's
say, because the kernel guys are a
special breed and they weren't
interested in my userland problems. It's
probably some issue in my code, right?
And they're probably right, but it
wasn't in this case and I was sure of
it. And so I kept adding asserts all
through the code to make sure that the
that the preparatory steps of adding the
stuff together were never more than 100
and that the final sum was never more
than 100. And finally, it never
But occasionally we would get this bug
where people would still see it. And so
I finally put my phone number in the
assert. And I was like, if you see this
message, call Davepl at 425836, my phone
number. Um, and finally, we did get a
catch in the actual stress debugger that
I was talking about earlier where it
happened to somebody with a debugger
connected. We were able to go through
and it was actually a kernel accounting
issue and it wasn't a task manager
issue. So they just fixed it in the
kernel once I was able to prove that it
was in fact the kernel issue. And uh
you'd think we would then remove my
phone number, but we just commented it
out. So it's shipped and it's in all the
damn source code leaks for NT that are
out there. So that's how I find Task
Manager code is I search for my phone
number on Google and it will reverse
find the empty source code.
Can you speak to the search thing? By
the way, I saw I think you tweeted or
you said somewhere that if you want to
take your search really seriously, you
add your your home phone number in
there. It's true. It's true.
A little facicious because it's probably
not the smartest thing, but you will
find out. But I mean, assert by itself
is already a serious thing because it
stops at all execution. I mean, this is
one of the reasons I really really love
asserts cuz they they stop everything
and force you to take care of the
problem. Yeah, I'm a little religious
about my asserts, too. I don't assert
things that I hope aren't true. I assert
things that I know cannot be true. And I
think that's really the intent of an
assertion, so I'm overstating the
obvious. But when it does occur, it's a
bug, plain and simple. It's not a
warning. It's kind of fascinating how
often it can really help you figure out
the problem because if you put asserts
everywhere, you can get very quickly to
the source of the problem.
Yeah, I tend to it's not something I
want to suggest you go back and add
later. It's something you should do
organically as you build your code. So
for each function, if you've got
assumptions like I know that this
pointer is never null, well assert that.
If you know this count is always less
than twice the bite width, assert that.
And don't be afraid because if it
asserts it's doing you a favor. I think
some people are afraid. You know, it's
like when you turn out of an
intersection and you think maybe there's
somebody coming and you don't look left.
Or maybe I don't want to do that. But um
it's like that people don't assert
because they're afraid they're going to
fire. Well, no, you want to know.
You mentioned task manager. Obviously,
we have to talk about this the legendary
program that you created, the Windows
task manager. Tell me every detail of
how you built it. What is Windows Task
Manager? So what is task manager is a
way to go in and find out which apps on
your system are using the computer,
using the hardware, using the CPU, using
the memory, and which ones might be
using too much or locked up or going
crazy. And it gives you the ability to
terminate and kill those ones. So it's
an inspection and a fixing tool.
Yeah. It lists all the processes. I
mean, it's a legendary piece of
software. It's crazy. I mean, you just
take it for granted. It's like the start
menu, right? Yeah.
It's like genius. Well, I had the great
fortune of working on a lot of things
that people are familiar with and task
manager was one of those side projects
that I started as something that I
wanted for myself and eventually came in
house. So I started writing it at home
and I got kind of the basics up and
running and I was using I think it's HQ
current perform or HQ performance in the
registry to get the stats because I
didn't have access to the internal APIs
because I was working from home and I
don't call those if I'm working from
and uh when I brought it in house then I
was able to call things like antiquery
system information or antiquery process
information and get the real answers
very quickly which enabled it to become
a very fast and responsive app. So
people have come to rely on it because I
wrote it to be as reliable as possible.
I wasn't worried about the features.
There was a basic set of functionality
that I wanted in there and I got
everything I wanted, but I wanted it to
be really robust and so that and small
and the original was like 87K.
Okay. Can you speak to what it takes to
build a piece of software like that that
doesn't freeze?
Uh, you don't assume much, right? If
you're going to call the shell to run an
app, well, that could be a network path
that's on a TCP IP share that takes 90
seconds to time out. So anytime you do
any kind of AP API call like that that
could take time you're gonna wind up
doing it on a separate thread and so the
app becomes a little bit more complex
because everything is multi-threaded.
Okay. So what programming language were
you working in?
So this was for Windows NT.
So this shipped initially in NT4.
Okay. So what are some interesting
details about this program because you
have to get as simple as possible
but also as robust as possible.
Now, what are some interesting
optimizations for example, you had to
implement?
There's a couple things I a little
hardcore now. I'm surprised I did. Like
I didn't want to link to the C runtimes
at all. So, I made sure never to call a
runtime call and I didn't link to them
and that saved me whatever the C runtime
is 96K or something. So, you know, it
almost double the size of the app if you
just touched any C call. So, I was
careful not to do that. But then I was
actually writing in C++ which is C with
objects more than anything. But uh in
order to get it to work, I had to go
through and call all the object
constructors manually from the dispatch
table and stuff because you don't have
the run times to do it for you. So
you're working with a compiler that
doesn't have its runtime. And I don't
want to rat hole on the technical
issues, but it's a lot of extra work to
get it to work, but when you do, it's
incredibly small and tight.
That's about the size of the program. Um
what are some interesting aspects of
tracking down like every every process
and how much CPU usage
in that process? cooler things that I
saw is I don't want to say I invented
Hamming code, but I kind of invented
Hamming code without knowing Hamming
code existed. So every column and every
row in task manager has a bit on whether
it's become dirty or not. And then I can
look basically the same way Hamming code
looks on your X and Y columns to find
out which rows have changed. Go through
and find out which ones actually need to
be repainted. So task manager is super
efficient and it works in concert with
the list view control which provides
that functionality to go through and
repaint as little as an individual cell
that changes from frame to frame. So it
can paint very fast. It can resize very
smoothly and resizing was probably my
uh personal goal with that app. So you
can size it to any size and it still
works. And even if you have 32 CPUs,
which wasn't possible in the day, it
will draw, I think, only eight graphs
and then it wraps. But, uh, it still
works today. So, kind of proud of that.
It's just incredible. Um, you've gotten
a chance to sort of observe the
evolution of Task Manager. In some ways,
it really hasn't changed much. Maybe
there's some prettier aspects to it that
fit into the whatever version of Windows
it's in, but it's really basically the
same thing. the functionality is very
same. Um the reporting is more because
they've added GPU and thermals and
things like that which is really nice to
have and we didn't have that ability in
the day. So
I mean what can you say? Do you know
about like was there any refactoring
done or is it basically the same code?
Uh as far as I know the original code's
still mostly all there. So there are
layers of drawing code and dark mode
code and whatever else XML schema code
that goes on top of that that makes it 4
megabytes instead of 87K. But that's the
world we live in.
Yeah, it's one of those pieces of
software you create and it just stay
once it's there. This is really like the
start menu and then I'm sure if you
remove it, people will just lose their
Yeah, it might be locked in for a while
on that one. It might be good.
Yeah, I thought that would be true for
Clippy, but
uh Clippy will make it back one day. All
right. What What are some um other
pieces of software you created at the
time that are legendary? So, you were
part of Space Cadet Pinball, at least
Yeah. So, they came into my office and
said, "Hey, what are you doing?" And I
said, I told them what to do. And they
said, "Well, how do you want to spend
your next 3 months?" I said, "I have no
idea." And he said, "Do you want to port
pinball?" And I had I'd seen Space at
Pinball as a game standalone for the Win
95 platform. And it had a couple
different tables. And it was a cool
game. So, I was kind of excited. And
what they wanted was some visual splash
for NT to show that NT can do for then
high-speed graphics and or at least
responsive graphics. And so I took a
shot and unfortunately a lot of the code
was in assembly and I was on the so I
had to rewrite the code in C so I could
then port it to all the different
platforms and at the heart of the game
is a huge state engine and it's like a
giant switch statement with if I
remember like 50 entries in it.
And it's got an Easter egg built in and
decoding the state. It's like running a
neural network through this thing as you
hit it with different states. and I just
put it aside and treated it as a black
box. And so my code runs on top of that
and does the drawing and the sound and
everything else, but the original game
is still running. And somebody recently
asked me, uh, why is it slightly
different? The physics are slightly
different from the Windows 95 version,
but it should be the same code because
I'm trying very hard to preserve that.
But what it is is I had a bug where I
will draw as many frames per second as I
can, which on a modern computer could be
5,000 frames a second for pinball
because it's a pretty basic game. And so
all your physics are interpolated 5,000
times per second instead of 30 times a
second or whatever you would have got in
the old one. So you're getting arguably
better, at least different physics.
But they fixed that since. So
why is that game so awesome?
I think it's a great design. I mean, I
take no credit for that. That's all
totally guys cinematronics. But the
original game is a great design. It's
very similar to Black Knight 2000, which
I own as an actual physical pinball
machine. And the layout is actually very
similar. I don't know if it was inspired
by it or not. So, it's a good game.
Yeah. Sometimes I think about like
Tetris, about certain games are pretty
primitive graphics
that captivate the uh the excitement of
a large number of people.
And maybe it's the excitement of a large
number of people that contributes to the
awesomeness of the game. So when when
many people together get excited and
talk about it, that sort of gets
implanted into your head. But that's one
of the great games. I mean, even even
like Solitary Mind Sweeper, I mean,
there's just a generation of people that
have gone to war in Mind Sweeper, right?
Well, those things were included in the
OS not as games, but as educational
tools to get you to use a mouse.
Oh, interesting.
So, Solitaire is there to show you how
to do drag and drop.
And Mind Sweeper is probably right
click. I think you put a right a flag or
something. Not a mind sweeper guy, but
so each one of them teaches you
something.
Mind sweeper guy.
That's funny.
Yeah. Wow. I didn't know that. That's
interesting. And that's true. But I
don't know how many hours I've spent on
these games and like millions of people
have spent millions of hours on these
I used to volunteer teaching computer
science in my kids' school, you know,
for the third graders and stuff. So,
it's more like logging in than computer
science. But, uh, the kids, of course,
all their dads work at Microsoft, so
nobody's impressed by anything you do.
But some one of the kids found out I
worked on pinball and then they were
like, "Whoa, you worked on pinball."
They all knew that in those days. Now
the kids are probably aged out. They
don't know it anymore. But for a brief
uh, you're behind the Windows
activation.
You're saying like it's a bad thing.
Um, everything's a matter of
perspective. So tell the story of that.
What's Windows activation? What uh how
did you get involved?
So they came to me late in the XP ship
process. I I don't know if the beta had
gone out. I don't think the beta had
gone out yet, but they had intended to
take the Office activation code and then
adapt it to Windows and add activation
to Windows, but whoever was responsible
for doing it had slipped it enough times
that it wasn't going to happen. And so I
had kind of reputation for being able to
fix things quickly. So they came to me
and said, "Can you get this done in time
for XP?" I don't know, but I'll try. So,
with the help of the guys that were
doing the DRM stuff on the DRM side and
the research guys doing the math for the
product keys and everything else, we
cranked it out in time for XP. And I
don't know what it actual impact is for
revenue, but I imagine it's substantial
when you start enforcing license keys.
I wonder what it is.
I don't know
cuz it's also annoying.
It is, especially if you have to phone
activate. And that was just the case
that we had to carry with us as an
albatross around our neck where you've
got to pass data up to the clearing
house, the backend systems that are
going to approve your key. You've got to
tell it all your hardware parameters
like how much memory and hard drive
space and the various things the
hardware key is bound to as well as the
product key. And you've got to encode it
in letters and numbers that somebody's
willing to read in over a phone. And if
you think doing product activation is
painful over the phone, could you
imagine being the person that worked on
the other end of that line? I mean,
that's just got to be a mind-numbing job
to listen to product keys for eight
hours a day.
Yeah. One of the challenges with
Windows, and it's been a frustration
point for me, but I I understand from a
design perspective, it's very difficult,
is so many different kinds of people use
Windows. But um it's been frustrating
how over time Windows has more and more
leaned into the direction of like
the not not the power user I should say
which is why sort of Linux has always
been really wonderful but from an
activation perspective or from any kind
of configuration it's been it's been of
it's been a source of a lot of
frustration.
Yeah. One of my more popular episodes of
late has been why you can't move the
Windows taskbar.
I had no idea. But the outrage is
palpable amongst people that you put on
the left or top and you can't anymore
and it is an affront to their existence
and I understand it to a certain extent.
That's one of the main reasons I really
just dislike. There's a lot of aspects
about Windows 11 I dislike. One of which
is like you can't customize things as
much about the position of the taskbar.
Just basic customization. Can we just
configure stuff? because there's going
to be a small contingent of power users
that are just gonna enjoy the hell out
of this operating system if you just
give them that option. It costs you
nothing. Just give them that freedom.
Well, it does cost, right? Because the
freedom to put the start menu on the
left or the top or the right really
increases the complexity of the code
that renders the start menu and lays out
the tabs and does all the things. And
now it's a much larger surface for bugs
and it's a much larger piece of code to
maintain. So you probably need more
developers or another developer or some
portion of a developer's time. So the
question becomes at what point is it
still worth it to satisfy the niche
needs of a small set of users?
And I I that those decisions weren't
mine to make but I could see it from
both sides. I think just like the people
who make movies
and insert very nuanced details that
only a small number of people will
realize are there that's going to really
pay off. There's a kind of reputation
that builds over time that has a very
powerful ripple effect that I think it
has it it has so many benefits
including for hiring great software
engineers. It's like you create this
aura of a place
uh that puts love into every detail
that puts that really takes care of the
power users that takes care of the
developers. I think Microsoft is more
and more moved in that direction with
GitHub and acquiring GitHub and just
taking care of the developers. But on
the Windows interface side,
come on. some customization with, you
know, with VS Code, you can customize
everything. Why Why can't we customize
the start menu? All right. Anyway, uh,
and the taskbar
um, and really every aspect of the
Windows interface. I don't I don't I
maybe you're right. Maybe increases the
complexity of the code. I suspect that's
just not the case.
I bet it was. I bet it was a scheduling
decision when they rewrote the start
menu. I think they rewrote it because
it's different than the old taskbar.
Mhm. and somebody was tasked with you
got to deliver this set of functionality
and if I cut out putting it on the left
and the top and the right and two rows
of tabs and all the other cool features
I can deliver it four months sooner and
I'm not saying that's the right decision
but I'm guessing that might be the kind
of thing that motivates it and they're
on such a different release schedule now
it used to be
you won't see much craftsmanship unless
somebody owns a component for a long
time and it settles to a point that then
you can work on and polish it right but
if it's always turnurning and the UI is
change in every release. It's never
going to get that level of polish.
Although I think the UI is pretty nice,
I Yeah, it is nice. But I think there I
think it's I just don't think it's a
scheduling thing. I think I think it's a
craftsmanship thing. Just like you with
a with a task manager. If there's a guy
or a girl in there who take ownership of
it who have like passion like for them
it's a thing that they take pride in
over a period of time. they can like by
themselves in a short amount of time
create something truly wonderful,
And like I I I think if you have large
software engineering teams with managers
and scheduling of meetings and all this
kind of stuff, yeah, okay, then then
your argument applies. But if there if
you allow the flourishing of individuals
that create cool and like their own
sort of the side project, which Google
is very good at.
They tried that, right? Google. Yeah.
Yeah. like have fun with it, like do
some crazy stuff and then we'll
integrate it. We'll we'll try to
integrate into the whole ecosystem. I
don't know. Yeah. Cuz like to me
there's it's such a great joy from an
individual developer to create something
like customization of the star menu of
the taskbar because you know that
millions of people are going to use it
uh the the taskbar and then you know
that thousands tens of thousands of
developers might be using to customize
even little subtle aspects of the
taskbar. You know how much joy you
you give to people to customize to have
some kind of JSON thing where you
customize something about the taskbar.
Okay. But how do you respond to the
Steve Jobs aspect of
giving you customization implies that we
couldn't figure out the right answer for
Or maybe there is no right answer and
all four answers are equally right. I
have no idea. But
right, uh I think I've always the I'm
glad Apple exists. It's a beautiful
thing and that ideal of design is
wonderful but I always thought that the
the Windows creates the contrast like
the point of Windows is to be the
operating system that works on all kinds
of devices that just much is supposed to
be much more open and they've moved
towards that direction more and more
with Windows subsystems for Linux. It's
just this whole developer friendly
ecosystem. it it the interface should be
in the spirit of that I think right but
but I do think that there could also be
security vulnerabilities that created
with that it's not just the complexity
of the code because Windows is just
under attack
it's very difficult to keep it secure
anyway taking that that tangent you also
developed the zip file support for
Windows uh creating visual zip like you
mentioned zip folders that eventually
evolved into zip folders tell the story
of that
so that was a piece of software that I I
wrote at home again and uh what What
happened was I was out with my wife and
I think it was a Sunday afternoon. We're
driving around. This is 1993 and we're
living in our apartment and we're just
seeing what the housing market is like
out there and there's a guy, he's got
this beautiful three-bedroom house and a
Corvette convertible 93 red torch red
parked in the driveway and house is for
sale and it's like 300k I think and
there's no chance I'm coming up with
300k at that point or even the down
payment on that. So, um, I took the
flyer and I cut the picture of the house
out and I taped it to my monitor. And
that was my incentive to just write
something at night cuz when I came home,
I was doing two things. I was one
expressing a creativity that I couldn't
get out at work when I was just fixing
bugs. And I was trying to make some
extra money. And so, I wrote a shell
extension before I actually went to the
shell team. I started it. And that's
what led to my interest in going to the
shell team based on a MSDN samp or msj
at the time msj sample that I saw on how
to like bring up a folder. Well, once I
had the very basic bring up a folder
template, adding zip file support to it
was just incremental all the way. And uh
I released it as a shareware product. I
think it was 1995 or 29.95 and I sold
whatever a couple hundreds or thousands
of copies. And one day I'm getting ready
for work and I get a call and it's a
lady and she says, "Are you Dave
Plameumber?" I said, "Yeah." And she
said, "Are you the guy that wrote
Migelzip?" I said, "Yeah." And she said,
"Well, this is Betsy from Microsoft, and
we'd like you to come by and come in and
talk about an acquisition of it." I
said, "Okay, what building you in?" And
she's like, "What do you mean?" I said,
"Well, I'll come by." And she said,
"Well, no, you got to talk to travel and
you got to talk to legal and this all
has to be set up." And I'm like, "I
don't get it. We both work at the same
place. Why can't I just stop by?" I
don't know if I said that literally.
But it was a few minutes of back and
forth where we both realized that she
didn't know I worked there.
Yeah. They had just cold called the
author and then found out that it was
And uh
So they made me an offer on it. And it's
the kind of thing where if I don't
accept the offer, now my choices are I
can keep selling my own version and quit
Microsoft or I can stop selling my own
version and work for Microsoft. Neither
of those is great. I mean, I keep my job
of course, but I'd like to still have
this income stream. And the other option
was accept their offer, which is what I
did. So then I bought a used 93 red
And you got to continue building it
internally.
I did. So we took a lot of features out,
right, to simplify because it had
encryption and it had a number of
features that were common in zip
programs of the day, but probably
weren't appropriate for Windows. And at
the time, encryption was like a
munition. So you couldn't just add
encryption willy-nilly to various parts
of the operating system. So we took out
some things like that. Multi volume
support, I think, was taken out just to
simplify it. Well, can you speak to zip
in general? Just the history of zip and
you know compression that whole thing.
It was really born out of the BBS era
when people were dialing in on modems to
download trialware and shareware and
other things from BBS's
online and to compress them. Executables
compressed about half their size. Other
stuff compresses much more. But a guy
named Phil Cass came up with a command
line program for MS DOS called PKzip
which was able to do compression of
programs and he has a rather tragic arc
but it became ubiquitous in the entire
PC industry and pretty much everybody
was using it. So when Windows came out
there was no way to open up a zip file
but everybody had been creating them for
a decade and so that really drove the
desire to have the zip support right
into Windows.
Yeah. And that's another piece of
software is just kind of with us to this
Mhm. And it could be vastly improved,
but you know, it was written in a single
core days, so it doesn't do anything
multi-threaded. And you've got a 96 core
795. Well, it uses one of them to unzip
your file.
What other awesome things were you a
part of at Microsoft? What other pieces
of software?
I worked on the initial prototypes of
Windows Media Center. So, we did that in
uh 96, I believe. And we didn't have at
the time any sources. So we had like a
CD of MPEG video files of Raging Rudolph
and I think the original South Park
video, the Christmas one,
which is all wildly inappropriate in the
workplace today. But uh it's all the
content we had until we got actually we
had them put a satellite dish on the
roof, a DSS, whatever the 18-inch dish
is because we couldn't get cable to the
building. And so we built up this thing
that would eventually look a lot like
media center and it was distance viewing
UI for windows. So you can sit with a
remote control on a desktop and have you
know the current start menu is not great
at 20 ft away. So
tell me the story of the infamous blue
screen of death.
What it is is when Windows has no other
option when the colonel gets into a
state where something illegal has
happened. So let's say a device driver
is trying to write to a piece of memory
it doesn't own or is trying to free a
memory piece of memory twice. Something
that just cannot happen and the colonel
has no other option. It will shut the
machine down to save your work.
Mhm. And well, not save it, prevent
further damage. And it puts up a blue
screen and it uh prints out the stack
information. Depending how your settings
are, sometimes just a sad face in the
current Windows.
Yeah. I wonder what the first version of
Windows where the blue screen came to
So, Windows 3 had a blue screen,
but it's completely unrelated to the
blue screen in Windows NT. And I talked
to the guy that wrote the blue screen in
Windows NT. His name is John Vert. And
uh the reason he picked white on blue, I
had thought I'd always heard this
because in the labs you could walk
through a lab where we have 50 PCs all
running stress. Oh, that one's got a
blue screen. It's crashed.
It wasn't that simple. It was just the
MIP's firmware that he was building it
on was blue on white. And Visual
Slickdit that he was using as an editor
was also the same color scheme. And so
you could code, boot, crash, and reboot
all in the same color scheme. Why do you
think so many problems with computers
can be solved by turning it off and
turning it on back again?
I think there's two major things that
happen with computers as you run them
over time. One is memory gets used and
not freed.
And so it accumulates on the heap or in
the swap file or wherever and things get
sluggish. And the other is code gets
into a state that the developers didn't
anticipate or didn't test very well.
And maybe that's a rare state, but now
that Notepad or Word or Excel is in that
state, your system is goofy. So if you
just reboot the thing or shut it down or
restart it, you're getting a fresh state
and there's no memory leaks. So it
covers a lot of sins basically. And uh
the intricate ways that several pieces
of software in a goofy state interact
with each other creates sort of a meta
goofy state that just kind of had just
the entire system starts acting a little
Yeah. and it somehow fixes it. What's uh
what's some of the best and the worst
code you've seen during that time in
Microsoft? What's some beautiful code
and what's some ugly code that pops to
Terms of beautiful code, there's two
that stand out for me. One is the kernel
in general when you get down into the
Windows kernel in the actual NT APIs and
stuff is very well written and it's
written to a standard that you don't see
on the user side or at least is uncommon
on the user side. On the user side,
probably the coolest code I remember
seeing was a guy named Bob Day wrote a
named pipe implementation to eliminate
the use of shared memory. So, Windows 95
had a big shared segment amongst all the
shell processes where it would store
stuff was common to all the shells. We
didn't want to do that. Shared memory is
a bad idea on NT and an industrial
level. So, he came up with a way to do
it with name pipes and uh I remember
doing the code review on it and it was
very impressive to walk through the
code. It was one of those things was
like, "Oh, I don't think I could have
done that if I was trying."
Who's the greatest programmer you've
ever encountered?
You know what? I don't think there is
anyone. I I've met a number of great
programmers, but I'll tell you one story
that impressed me a lot was when I was
brand new at the company. I've been
there like six weeks and I'm working on
this Olay presentation cache that I
mentioned earlier, and I'm on Windows 95
and I've got Excel inserted into Word
and I'm in the kernel debugger and
something's going wrong in theuler. And
I've been there, you know, I've barely
written any x86 code and I'm looking at
the Windowser trying to figure out why
my thing is deadlocked.
And eventually I get stuck. So I'm kind
of out of my element. And I send an
email to the Windows 95 kernel team and
say, "Could you send somebody by?" And
so about 10 minutes later, this
developer strolls in and they're just
holding a null modem cable, which is to
connect my two machines together so they
can debug one with the other in case I
didn't have it, but it was already set
up. And so they sit down and they're
using wind debug, which is just a
horrible debugger. It's just it's a
cursed. But uh they're very very
competent with it and they are just
blasting through the call stacks and
they're checking all these objects in
the kernel and trying to find out who's
waiting on what and why things are
deadlocked and what things are signaled
and what's not and it's just this quicks
ballet of call stacks flying by and I'm
watching this and I'm pretty blown away
because I'm a good programmer but this
person is an amazing debugger and I've
never seen a performance like this and
uh about five minutes in I just hear oh
and then they disconnected and got up
and left. And that was Laura Butler who
became a distinguished engineer at
Microsoft. I think she may still be. I'm
not sure if she's retired or not, but so
she kind of set my template for, you
know, what Microsoft developers were
like when they were debugging and what
kernel developers were like and even
what female developers were like cuz I
had such a small sample set. Um, but it
was a very high standard. There's a few
things I love in life more than people
who are ultra competent at anything
really. But the lower level the better
in the engineering space. They're able
to for example like run or maintain the
infrastructure, the computer
infrastructure. So not the individual
computer but the computers communicating
together and working together. Those
people are just magicians,
It's so inspiring to make. It's like
watching a great carpenter or
I love anything done really really well.
Yeah. It's beautiful to see. It's
beautiful to see that humans are able to
accomplish that. Even in in civil
engineering space when I look at like
bridges, it's like the number of people
that had to come together to build that
and now millions of people use it every
single day. With software sometimes you
don't get to see visually just the
number of people impacted by a thing.
Imagine how many people are impacted by
Linux and all the different open sources
open- source systems that make up Linux.
It's incredible. And Task Manager is an
example of a piece of software just how
many people use that over the years. How
many times? It's crazy. It's probably
billions. Billions of you.
Yeah. Two billion a month or something.
Two billion
something like that. I've seen the
metrics and it's up there.
Crazy to you.
It is. What I love about it though, and
I'm sure you've had this experience
where sometimes you design a piece of
software and it's complex and you get it
working in your head and you get the
plumbing working and you know how it's
going to run and flow and then
eventually you write the code and the
code does that thing that you had
pictured in your head.
And now there are billions of copies of
that thing that I had in my head running
on millions of pe or billions of
people's machines. And that in itself is
really cool to me. It's not a vanity
thing so much as a uh I'm impressed by
it, I guess. Uh, how's your programming
evolved over the years?
I take a lot more care and complexity
these days. So, it used to be you would
write code and just keep writing code
and writing code and then at some point
I go back and clean it up. Well, I write
the other way now. I try to write really
clean initial skeletal code and then
flesh it out because I have been
involved in too many projects of my own
and of other people's makings where
things get so messed up that they're
just not fixable.
And so sometimes the work you put in up
front pays off, you know.
What programming languages have you used
over the years? What's been your main
For me, it's been C++ and assembly
And still to this day, C++ is really
what you lean on.
Yeah, right now I'm 100% Lua and Python,
but that's just side project I'm working
on. So,
can you speak to the Lua and the Python
detour that you took? And uh what do you
love about C++?
What I'm doing is I wanted to build an
AI to play the game Tempest. That's the
old Atari Game Tempest. And uh this is a
game that I actually hold the world
record on. And uh
you take me to this Atari Game Tempest.
Okay. Atari Tempest. What kind of game
is this?
So it's a 3D vector game from 1980. And
it's a very complex game. You got full
360 degrees of motion. You have eight
shots on the screen. There's like 11
enemies. There's spikes. So it's a very
complex game. It's not like trying to,
you know, do Pong or something.
Okay. And what I wound up doing was
first taking the ROMs out of the machine
and reverse engineering the code. So I
got a sense of where all the code in
Tempest lives and what it does, where
the zero page variables are, where
things live. Yeah, there's one.
So what? Oh, wow. That's a very
geometric.
Okay. What uh can you explain to me the
That's me playing the game right there.
This is literally you playing.
This is me. Dave is the high score.
You'll see in the top center there.
Can you explain to me what I'm looking
Well, it's a 3D geometric world. It's
basically 3D space invaders wrapped into
a shape and the enemies descend from the
center of the tube towards the outside
and they all have different behaviors
and wow.
So, long story short, it's a fairly
complicated game to play well and I
wanted to see if I could get an AI to do
it. And so once I had figured out where
all the interesting parts of the game
lived in memory, I added them as
parameters and built a Lua app to
extract everything from the game's
memory as it's running and put them
together as parameters which sends it to
the Python side over a socket and then
the Python side does RL learning. I'm
using a dueling deep Q and I believe
to uh with two a head and a tail and
they chase each other and it can play up
to about level 36 now which is way
better than most humans but that's level
96 so it's got a ways to go yet but
and uh you're the red thing shooting.
You're controlling the red thing that's
Okay. What are the options? You can just
move clockwise or counterclockwise and
then you can shoot.
Yeah. So, you have a rotating knob,
which is an optical spinner, and you
have a fire button and a super zapper
for emergencies. But, uh, that's it.
Fire and rotate, basically.
All right, let's get back to your
favorite C++. What do you love about
C++? Why have you stayed with it for all
these years?
Because it allows me to encapsulate my
favorite C code in classes. I'm not a
big Well, I actually
You're really a C guy. Okay, I got you.
Yeah, I'm really a C guy. Although, I
write two kinds of C++. I write really
modern C++ 20 using no pointers, no
string or no character strings. Uh so
there, you know, it's basically as safe
as Rust as far as I'm concerned.
Or I write C with classes which is
standard C but you know with
polymorphism encapsulation and that's
most of what my code is. But uh I try to
do both.
Let me ask you about the whole stretch
of time that we kind of skipped over. Uh
you built a lot of software over the
years after Microsoft on the side while
at Microsoft and afterwards a lot of
successful pieces of software. Uh one of
your companies was software online and
it got into trouble for nagging users
too much I guess.
To upgrade. That's what I saw. What was
all that about? And uh what did you
learn from that experience?
Well, that was other than like family
health scares, you know, when kids are
sick. That was the scariest time of my
life. And the period leading up to it
was one of the most invigorating and
exciting because what had happened was
while I was at Microsoft, I had written
all these shareware utilities and was
selling them on the side and sold one to
Microsoft as we talked about and they
started to do really well. And then I
discovered banner advertising online and
so I signed up with my credit card for a
site I think was called FastClick. And
you could say I will pay this much for a
banner ad impression. Here's my banner.
And it would rotate it in. And I didn't
set a cap on it. I came back on Monday
and I saw I had spent like $10,000 in
banner ads. I was like, "Holy crap, how
am I going to explain this to my wife?
This is a bug. This is a mistake. It was
my fault." And I looked at the sales and
it had made like $38,000 worth of sales.
And I was like, "Holy cow." So, all I
have to do is scale that at some point
and basically did that for the next
several years. And the reason we got in
trouble was the AG came in and they had
well I was blown away because they had
like 12 court claims of action and 10 of
them were outrageous which to me as a
person with autism I couldn't get past.
It's like I know these 10 things are
absolutely not true. Why are we even
here talking about them and then all
they care is the two things that might
be true. And the two things that might
be true were that it was a 30-day trial
version. And after your 30 days were up,
it would then if you continued to run it
and not buy it or uninstall it, it would
remind you once a day, not like every 10
minutes, but once a day or every time
you booted your computer at most, once a
day. And the AG contended that was too
often. It amounted to spam. And so we
agreed with them to limit it to once a
week, I believe. And you know, there had
to be a button to just uninstall with
one click. So we did those kinds of
things. The other one was in those days
when somebody bought a piece of software
even if they bought it online and got a
download they fully expected there would
be media showing up at their house. So
in the year 2001 which we're 2001 2003
we're talking about if you bought
software there was an expectation that a
disc would show up and so we made that
the default was to fulfill by disc and
it was 3.95 or 4.95 extra and it was
very obvious but it was a checkbox and
it was turned on to ship the disc to
your house cuz we found if we didn't do
that we got all these calls people would
wait they'd order 2 weeks later call
where's my disc and we look we didn't
order a disc well cancel it all I don't
want it cuz I'm not waiting for it and
so we got a lot of returns and we didn't
include the disc and so we decided to
include the disc but that is a a
priority violation of negative
affirmation billing in Washington state
because you're giving them a default
higher purchase price. What about on the
user relationship? It's interesting like
how often to annoy the user with a
right? If you never mention anything,
they might never discover
like something they actually want,
But if you mention it too much,
then they can get annoyed.
Yeah. And what you don't want is you
don't want them to have to do it or buy
it or do something to get rid of it.
That's one of the things that bothers me
with um I think Windows does that a
little bit still to this day where it
bothers me by asking me certain
questions like do you want this like um
it for example I really don't like to
use my Microsoft account to log into
Windows right I think now it's like
basically required I think there's just
no way around it but like they make it
so difficult to not do that it's almost
like they think they could just trick me
into they it really does feel like I'm
getting tricked into
not doing what I want to do
like is I have to like think okay I need
to click skip and it'll do something are
you sure like I have to like use too
much of my brain to do the thing I like
you know as an as an interface you know
what I'm trying to do you're trying to
trick me into not doing the thing I want
to do. And what I hate about that is
it's probably effective, sure, for
converting people, but it's really
not good long term for taking care of
the interest of the user.
Yeah. The one that really throws me is
the use recommended settings. So, I just
did a Windows upgrade. It went through
the steps and I'm going through this new
dialoger wizard and use recommended
settings. Sounds like the thing you
should do, but I'm pretty sure that
resets you to using the Edge browser and
all this other stuff. So, yeah,
recommended by them, but not recommended
for me. And that's the difficulty.
That's a really good example. Like, what
effect do you think that does in
resetting the default browser to Edge?
Do you think you're going to really earn
the loyalty of a user if you do that?
Don't don't you think that they're
actually what you're going to create
you're going to create some passive
loyalty from some user base. So on the
metrics it might actually look like
you've increased the number of edge
users but really it's that reputation
hit you take over time where it just
forms where the edge is the thing that
you can't quite trust
unfairly because I think Edge is a
really great browser but just this this
unpleasant feeling I don't know what
that is and the
well you don't want your oper operating
system to be an adversary right and
sometimes that Windows can feel
adversarial like it doesn't have your
best interests at
And that bugs me to a certain extent.
I mean, we have this feeling, I think,
we just have general distrust when
somebody is super nice to you and is
basically selling something. There's a
certain aura about that kind of
interaction. And when an operating
system is interacting you with you in
that way, it's like, yeah, I would much
rather pay $1.99 for Windows Pro per
year or 20 bucks a month or whatever the
fee schedule would be and not be upsold
any further and not have my data
monetized and those kinds of things. So,
Did you learn about finding the right
balance from that?
Yeah, I I mean I'm way more self-aware
now. There's things I would do much
differently, particularly in terms of
the advertising. I always figured
there's a guy named David Oglevie and he
did this ad long ago for the Volkswagen
Beetle where it had a picture of a
beetle, black and white, and it just
said lemon
and there was a block of text below it.
So, it's clickbaity and then
informational. And I always tried to
follow that pattern. But there's three
ways to sell something, I think. And you
can use sex, fear, or greed. and sex
doesn't work very well for software.
Fear works well for antivirus and stuff,
but not so much for optimization and
make your computer faster utilities. And
so I always tried to cater to the greed
aspect. Uh, you know, make your computer
faster, get more RAM available, whatever
the value proposition is. But I realize
now that I'm looking at that with my
knowledge and as an autistic person, I
now have an appreciation that other
people are going to look at it with
their background knowledge and may
conclude something different. So, I
might be scaring people where I was just
trying to incentivize or get their greed
instinct going. So, I'd be more
sensitive about that kind of thing
Ridiculous question, but what do you
think is um the top three Windows
operating systems, the different
I'm a fan of Windows 2000 server. That's
That's what I ran my business on and I
ran my brother's business. We set up
multiple salons all VPN to one another
and using the SQL server.
I don't know if I've ever gotten to
experience Windows 2000 server. So, when
was XP out?
What was before XP?
2000. Was that good?
Yeah, I liked it. I mean, it doesn't
have the visual flash that came with XP,
but as a system and especially as a
server operating system, it was great
for the day. But then XP was
I would say probably
from a completeness perspective and
impact and how long it lasted. It was
probably the the greatest Windows from
for consumers the operating system.
I would think so. It certainly got the
longevity for it. There's people would
still run it. I mean I'd still run it on
stuff if you get security updates cuz it
does 98% of what I need Windows to do.
yeah, that was incredible. I mean, so
Windows 95, I'll probably put Windows XP
as the number one for me and then
Windows 95 too.
What's your metric? Personal preference
or industry impact or
industry impact stability just there's
certain like just like with programming
you have code smell like how well all
the features were orchestrated together.
how there's a
design philosophy that permeated the
whole thing and was consistent, not too
many features, not dumbed down too much,
Uh but not over complicated, how often
it crashes the blue screen, all those
I don't know if it's a very apt
description, but I think of it as crisp,
so there's not a lot of rough edges. It
does what it does. Does it snappy? Yeah,
you said you play slot machines and uh
given that you uh love hardware and
software, you're the perfect person to
ask uh how do slot machines work?
Well, I'm happy to ruin them for you.
so it's ironic to me that I play slot
machines cuz I know it's a losing bet
overall, but there's a whole dopamine
feast there of bright lights and high
contrast colors that I enjoy. So, I do
play them. But what happens is
internally there's basically a black box
mechanism that does nothing more than
generate the next random number and what
the outcome is in terms of uh
probability and payout and then the game
says I got to make up a movie to go
along with that and maybe it's three
bars or whatever it is but there's no
correlation. It's not spinning the reels
seeing where they land and looking that
up to see what you won. It's completely
the other direction. It determines
whether or not or if you won and then
make something up to fit that scenario.
that that indeed is ruining it for
a little bit.
Uh what kind of code runs them?
I don't really know. I tried to get down
and get inside access to one and it was
very hard. They don't want to tell you a
lot about them. I'm sure it's not that
deep of a secret, but
cuz they're all basic Windows PCs, but
they're basic Windows PCs on top of a
very secure enclave of some kind that I
don't know a lot about.
Yeah, it has to be extremely secure,
Yeah. Well, in the 70s or 80s, there was
a tech in Vegas went around and he was
burning his own ROMs for the slot
machines and with a back door in them.
And so when he serviced the machine, he
would just put his ROM in and he come
back 6 months later and
invoke the back door.
I love humans so much. Uh anyway, do you
have do you other other favorite kinds
of uh systems like that?
I like a lot of old hardware. I restore
cars, so I do a lot of 1960s muscle
cars, cars and trucks.
And uh old computers. So, I restore
PDP11s has been my fascination and my
special interest for the last 6 months
or so, and I've built a number of those.
Yeah, you uh I've seen like you posting
uh videos about it, the PDP183.
Uh what's that whole project?
So, basically what it is is I had built
a number of PDP11s. And so over the
years I had acquired all these parts and
I decided well let me build the best
PDP11 that I can
and so it was kind of a quest to just
like you try to max out a PC I try to
max out a PDP11 so it's got 4 megabytes
of memory which would be massive in the
day and yeah that's it there
and it's got lots of blinking lights and
I had to rewrite the BSD kernel to make
the lights work and
what are we looking at here? What is
So the very top is a PDB1 1170 control
panel which we can largely ignore and
then there's two chassis below that one
what are the different knobs? Sorry to
ask dumb questions here.
Uh the knobs in uh control what view you
get of the LEDs.
so normally you see the data bus and you
can see the address bus and you can
pause the machine and you can edit the
address on the bus and you can deposit
stuff into memory with the switches.
Man, the haptic
plus the LEDs.
That's what you like imagine a computer
to be. That's so cool.
That's so cool. And these are what? What
are these? These are DU1, DU2.
Yeah, it's a weird floppy drive. It's a
dual floppy drive with one stepper
motor. So, both heads seek together like
Siamese twins.
Okay. So, what what kind of stuff are
you doing with this? What are you trying
to restore them?
Yeah. So, I restore them. And
does it actually run?
Oh, the blinking lights are real.
Yeah, it's all real.
Then I had to rebuild the kernel and all
that. decided to learn the BSD kernel.
I'm pretty familiar with it now
to get because you can't just add a
device driver, right? You've got to
rebuild the kernel to add support for
whatever device. So, you add a new disc
controller.
It's time to build the kernel. So, you
got to go find the source and find the
code and
you can run code on this.
Yeah. Uh you've written a couple of
books on autism. Being autistic
yourself, I was wondering if you could
tell me about like fundamental
differences about the mind of a person
with autism versus a let's say a
neurotypical individual. Well, the
fundamental theory of thought for autism
is called monotropism. And basically
what that means is that my brain does
one thing. It does it very intensely and
then when it's done, I can move on and
do something else. But I'm not a
multitasker. I'm a serial single tasker
by any stretch. Um, autism usually
brings with it sensory sensitivities and
repetitive behaviors, behavioral issues
that compound it. And if they rise to
the level where an individual can't
moderate or accommodate them in their
life, it becomes a disorder. And that's
probably 1 to 2% of the population.
What's the biggest benefit of life with
Um, I can bring to bear an incredible
amount of focus and dedication on a
particular task if it's and it has to be
something I love. It has to be something
that's rewarding. It has to be something
I can make progress on. And there has to
be all these things that are true about
it. And it could be like a kid playing
with trains. I get that same feeling.
That said, you also uh said that you
struggle with uh ADHD.
Yeah, a fair bit.
So that's part of the component like
maintaining the focus
or actually acquiring the focus is the
issue. So I'm very easily distracted. I
fall asleep with noise cancelling
headphones or I can't fall asleep. That
kind of thing. But once I get locked in,
I'm very hard to distract. So it's kind
of a paradox.
Oh, that's fascinating.
It's hard to get into that state.
Okay. What's the biggest challenge of
life with an autistic mind?
That I don't know what anybody else is
thinking. So, I know what I would think
about this interaction if I was in your
position and I was you.
And that's the best I can do. But I
think most neurotypical people have a
sense of, well, Lex probably feels this
way or that way cuz he's acting this way
and his reactions are this and his
facial expressions say this. And that's
all kind of lost on me. So, I run a
little proxy NPC game for everybody I
deal with.
So, I guess that makes social
interaction a little bit complicated.
It can be. Yeah. Telephone is especially
hard because I rely on a lot of other
cues. And when somebody is just on the
phone and I just have their voice,
there's so much that's implied between
people that I miss. And so I'm much
better on FaceTime where if somebody
makes a joke, they might smile after
where on the phone I don't know if
you're being sarcastic or serious and
that kind of thing. So
So that's probably gotten you into
trouble over the years a bit.
Yeah. There's lots of times with my wife
too where uh well to there's a certain
literalism that comes with autism and we
spent years where she would say
something and I'd say but that doesn't
make sense. She you know what I mean
like no I know what you said and I'm not
being just combative here. I literally
only know what you said and I don't have
that. And uh I remember we've been in
meetings with people and uh you know if
there's three or four people in the
meeting and I'm the only autistic
person, I'll tell that they've got this
communication loop going on and I feel
like you guys got to tell me what's
going on cuz I really don't know what's
being said here. So
you told me related to this that there
there was an early somewhat awkward
encounter with Bill Gates. Uh can you
share this the story of that uh
interaction and how autism comes into
play here? Yeah, my very first summer at
Microsoft when I got the internship,
Bill had uh all the interns over. I
guess it was 20 or maybe 25 of us uh
that got hired that year over to his
house for burgers and beers and just
chat in the backyard.
And of course, it's still Bill Gates and
he's a big enough deal even then that
you're a little nervous. And so my
manager Ben, who was sort of my mentor
at the time, took me over to introduce
me to Bill because he knew him. And he's
explaining this to Dave. He's our intern
from Canada. And in the space of four
months, he's done this feature in disc
copy and smart drive. He listed off all
the stuff I was doing. But I stopped
because I'm like, well, actually, it was
3 months. I had to interrupt them and
they both kind of what? And they looked
at each other and I realized that was
the wrong time to
correct the guy. But uh
Yeah. So you they bother like little
inaccuracies.
Oh, it drive me crazy.
And then you of course you don't
the the impact I might have on a on a
casual social interaction.
It's it's not trivial for you to be
aware of that.
Yeah. I'm much better than I used to be.
Before I didn't know and I didn't know
how injecting a correction meaninglessly
into a conversation could impact and
make the other person feel. Now I got a
better sense of it. What advice would
you have for folks who have an autistic
mind on how to flourish in this world
in terms of prosperity and finances? The
biggest thing I can say is sell what you
can do and not yourself. Because if you
go into a job interview and you try to
wow them with your personality and how
amazing you are, it may or may not go
well. But if you can go in with your
portfolio of work and say, "Look, here's
my GitHub history and here are the
awesome projects I contributed to and
here's the actual algorithm I wrote and
this is what I do." I think you get a
lot further with that. So whether you're
playing the piano or writing code
that said so much of software
engineering on uh large teams has a
social component to it. Right.
It does and that was a liability for me.
How do you how do you I mean what have
you learned about how to solve that
little puzzle?
I think the biggest deficit for me was
when I started to manage people because
now you're
concerned about their hopes, dreams,
aspirations, what motivates them. They
have entire lives that are kind of a
mystery to me because I assume they want
to be motivated and led and encouraged
and compensated exactly as I would.
And that's not always the case. Some
people need a lot more affirmation. Some
people just want money. Some people want
to be in the important meetings and make
decisions. But I was largely oblivious
to that. And so eventually I had to
learn that everybody that you're
managing has their own set of incentives
and priorities and they're completely
different from what I think they
probably are. So you could, I guess,
make things more explicit and just
communicate better about like ask them
about what their interests are.
And that's something I started doing is
overtly asking because it's hard for me
to nudge somebody there. I'm not good
with that kind of social dance. So
yeah, part of the social dance is
there's a lot of stuff that's uh unsaid.
you can kind of figure out you can read
people but if that's you know with with
autism it might be a little bit
difficult to do that and so you have to
make things more explicit plus like
sarcasm and satire and humor might be
difficult. Yeah,
I would love to be a fly in the wall
some of your earlier interactions with
Microsoft.
Uh I mean some of the greatest engineers
have mine like this. So
yeah, I've had laptops thrown at me and
stuff and I'm sure it was my own fault.
uh you write about the 10-second autism
test. Could you explain how this works?
Yeah. Now there of course anything that
has two answers has a high air rate, but
uh so what's more important to society
as a whole from the people? Is it
cooperation or creativity? And if you
had to pick one, which is the most
important? And most neurotypical people
will generally lean towards cooperation,
whereas people on the spectrum tend to
lean towards creativity as individual
problem solvers.
Of course, there's some kind of error
rate there.
So, if you want to double your
precision, you can use the second test,
which is you ask, there's a room with 10
chairs and six people come in and sit
down in those chairs. How many chairs
are left?
Now, some people are going to say four,
but I'm going to say 10 because that's
how many chairs are still there. clearly
And I'm not being a dick. I'm not trying
to be complicated, but that is how my
mind works. And so when I see that
question, it's like it depends how you
answer it.
So you're how literally you take things.
Yeah. Everything is very literal for me.
I remember as a kid, my grandfather was
building a planter holder in the kitchen
for my mom and he was using these big
angle brackets that I thought were a
little overkill. And I said, "Do you
think that'll be big enough to hold the
plant?" And he says, "It'll be big
enough to hold a horse." and I was only
five, but I was very confused about a
why you would bring a horse into your
kitchen, why you would put a horse up on
a planter and all of these things. It
didn't make any sense to me when
obviously it was a figure of speech, but
for a lot of my life I took figures of
speech as literal. So,
uh you mentioned uh emotional
post-processing as a strategy you use to
replace social interactions so you can
sort of reverse engineer to to help you
understand the neurotypical world. Can
you I think this is going to be useful
to a lot of people like what what does
that entail? How does that help you?
So, if I meet somebody, particularly
somebody new, and it's my first couple
interactions with them, is even meeting
you today, then I will go home later and
replay all of the moments where I had
choices to make and probably the most
uncomfortable ones first to find out
what did I do wrong in that moment, what
did I miss, what was the other person
thinking, how can I improve that kind of
situation next time, and do I need to go
fix it or make a phone call? That kind
of thing in a bad, you know, in a
extreme case. But uh and that's happened
a couple times in my life. Like I had a
car restored that my dad had bought new
in ' 69. I still have it. So we've had
it 50 years and about 20 years ago I had
it restored and it was like a three-year
process of craftsman working on this car
for thousands of hours. And I go out to
pick it up and I'm inspecting the car
and I'm very impressed with the work and
I'm saying, "Oh, this is nice and this
is great." And everything else and then
I fly home and write the check and the
car gets delivered. And then I realized
probably 10 years later that I had a
whole bunch of craftsmen that had worked
on my car for three years and I probably
should have blown some smoke up their
butts about what a great job they did,
but I never did that because it's not
what I wanted or needed in that moment.
And I was completely oblivious to that.
So I sent an email to the manager or to
the owner of the place and I said, "I
don't know if you remember this, but 10
years ago, I picked up my car and I
probably looked unimpressed, but I want
you to know that I was very impressed
with everything and the quality,
everything else." and he wrote back,
he's like, "I've thought of that moment
So, I'm like, "Now I'm glad I brought it
There's subtle things about human
interaction that mean a lot to people.
And if you ask them straight up, they
might not be able to sort of articulate
that, but it means a lot. And when it's
off, when something is off, it bothers
right? But to to reverse engineer that,
to figure that out for a person who
might not sense those little subtleties
of human interaction is tough. That's a
good point to jump in there too on
empathy because there is some perception
in the community that people with autism
lack empathy and I don't think that's
the case at all. Um I can only speak for
myself. I feel fairly empathetic. But I
think the problem is a communication one
and it works in both directions. whereas
I don't know how you're feeling. So,
it's hard for me to be empathetic with
it until you communicate to me what it
is you're experiencing. And then once I
know once I have an understanding of
what's going on in your head, I can feel
incredibly sorry for you. But other
until then, I'm going to assume you're
going to handle it just like I would in
your position in my case with what I
know now. What advice would you give to
people like on the other side how they
can help you be a better friend or
better partner, better colleague, like
how they should communicate with you to
help like give more information.
Yeah. Be really specific and don't
assume I'm going to pick up on clues and
nuance and subtlety.
So, if you're trying to nudge me into a
particular behavior, you're much better
off to say, "Dave, this is what you need
to do."
Have I failed in any way today?
No, not yet.
All right.
What what what score would you give me?
1 to 10. Am I a six a seven
communication? 75 floating point. Nice.
Uh masking. You got to tell me what that
is. Uh
it's a significant experience for many
on the spectrum. What is masking? And uh
tell me about any of the experiences
you've had with masking. So masking is,
and it's probably not the right way to
describe it, but it's the act of acting
normal. And that is how do I conduct
myself in a social situation in a way
that other neurotypical people are going
to or that other people that who are
neurotypical
are going to receive and accept it the
right way. Mhm.
And everything you do in a social
interaction from waving my hands to
taking facial expressions to tone of
voice to posture,
it's a huge contrivance and it's work.
Comes natural to most people. It's just
what they do and cool people do it
really well. But for somebody on the
spectrum, you've got to fake it all.
Uh yeah, acting normal.
There's a song by Rush. You know the
Yes. uh limelight and it's written by
Neil Per and I I only speculated about
people that have passed on. So I've got
a sense he was probably on the spectrum
um but the line is something like all
the world's indeed a stage and we are
merely players performers and portrayers
each other's audience and he talks at
length in the song about you know not
being able to treat strangers as friends
and being able to fake an affect and all
that so it seems like he's struggling
with masking a lot in the song and I
have no idea but that was what I took
from it.
Yeah. You describe meltdowns as an
overwhelming experience. Can you
describe meltdowns? What what typically
triggers a meltdown?
Generally, it is. It's when you're
emotionally overwhelmed to the point
that you can't manage your behavior
anymore. And so, you see it in the movie
Rainman when he's trying to get on the
airplane and he's kind of forced and he
starts losing it. That's a meltdown. Or
I've seen it on they did kind of a
actually probably the best portrayal
I've seen in media is uh what's the TV
show where the doctor is autistic?
He's a Anyway, there's a TV show where a
doctor is autistic and he's a surgeon
and he is eventually banned from surgery
because of his autism and he's always
wanted to be a surgeon and he has a
complete meltdown and it's a pretty good
portrayal on television. So,
what is actually happening? Like there's
like a threshold you cross that it's
just like
yeah a switch flips.
It's like blue screen
essentially.
Yeah. Kind of
for the brain algorithm.
So switch flips you go kind of a
primitive brain. Your frontal cortex
shuts down to an extent I think. So you
don't have the benefit of decision-m and
filtering your very reptilian brain in
that state. And it's really a panic
state. And so it's a panic and a fight
orflight response to not being able to
tolerate the current reality. And
perhaps it's been so frustrating or
you've been so randomized or you had a
bad travel day or an argument at work or
whatever. It's added up to the point
that something has now triggered you and
your brain loses its ability to
adequately moderate your behavior.
Uh what about love and relationships?
What are some of the challenges of that?
And you know there's a show Love on the
I've heard of it. I've not seen it, but
I've heard of it
because certain aspects like literal
interpretation of things. It just makes
the complexity of relationships of
romantic relationships even more
explicit in that in that context. You
know, I've been married 31 years and
together for 37, so a long history
there. And I think our first indication
that we knew we were very different was
we were sitting in the car one night out
front of the house at dark. And across
the street, there's kind of a nice house
and it has these big brick pillars that
are linked by like anchor chains and it
forms a fence around the yard. And I'm
looking at these things cuz they're
about 2 ft square and I got a capstone
and I'm like, I wonder if they're hollow
or are they back filled? Are they
filming with concrete or what? And my
now wife looks at me and she's like,
"What's wrong with you? Why do you have
a place in your head that cares about
And we just knew in the moment that I
was passionately involved in caring and
she was passionately involved in why
would you even worry about that kind of
thing. Knew her very different. So
yeah, very specific, seemingly
irrelevant details.
But uh I was never good with people.
I don't get it when people like me, I
guess. And so I got and my son is the
same way because they all don't fall
very far from three. And I got him a
t-shirt that says, "If you're hitting on
me, please let me know and be specific
because I'm clueless." And it's very
similar for me. I mean, I had to be
around a long time and kind of grow on
people because I had no game because I
had no ability to do the social dances
that that whole thing requires. So my
only option is to just be myself and
that works for some people.
Were you able to say like like I love
you, that kind of stuff.
Yeah. Uh, I mean, her family was way
more open with that kind of thing than
mine was. And so, it was a growing
period for me, but yeah, that's not a
problem I have.
Okay. All right. But, but it seems like
unimportant. Uh, like, what is that
actually accomplishing?
Well, now we do a lot of affirmation and
checking. Like in the last couple years,
we do a thing where she'll just be like,
"You good?" I'm like, "Yeah." And
there's two steps to that. There's the,
"Are you good?" And then there's my
response because if I'm like, "Yeah."
She knows something's up.
Yeah. And so there's always this pinging
back and forth because there's not the
ability to read people just from looking
at them to know what's going on. So we
have this explicit check mechanism I
think where we've
developed that.
So there's a vast chasm between Yeah.
and Yeah.
Again that subtlety of human
communication.
Uh you've uh written about the
experience uh that people have of
feeling quote a little bit autistic.
Could you elaborate on this concept?
Yeah, I think a lot of people, maybe 10
to 20% of the population is somewhere on
the autism spectrum, but isn't impacted
by enough that it rises to the level of
a disorder, but they still have many of
the characteristics that arise from
autism. And I think if they can
understand and identify and manage some
of those behaviors in an optimal way,
they can both leverage them to take
advantage of some of the skills and
mediate some of the deficits and
problems that come with it. And I wrote
it mostly for my kids because none of
them, as far as I know, have ASD, but
they've all got certain aspects of my
behavior that are particularly related
to it. So, thought I'd write a little
manual for them, basically.
Why do you think so many programmers
like excellent like great programmers
and great engineers are on the spectrum?
I think it's that single-minded focus
and the ability to reduce a problem and
to be ultimately curious about what's
inside stuff. That's been a obsession
for me my whole life. what's inside. I
got to take the my mom's oven apart
because I got to know how the flip clock
works. Um, and I think that's a good
habit to have if you're going to be a
programmer.
And being willing, being excited to get
into the details.
Yeah. Uh, what's a cool thing you uh
hope to program to build this year? What
are you working on? So, we got we got
the RL learning how to play Tempest. Uh,
where are you on that, by the way? How
like where what's the ETA on success and
like victory? Well, it's very close to
working. Um, I I think now it's tweaking
the model size and layers and stuff like
that to get it to learn past the one
threshold, but you know, it's a couple
thousand lines of Lua and it's a couple
thousand lines of Python and they all
interact and they all work. So, it's
like 95% of the work is done. Now, it's
tuning hyper hyperparameters and hoping
for the best.
So, it's already a success in a sense,
but like now you're seeing like how far
can this go?
Yeah. My goal was to be able to beat me.
Huh, that's a tough
It is, but lots of games now are, you
know, they play them better than humans,
but maybe not games this complex.
Uh, what other cool things are you
working on? What do you hope to build
this year?
Uh, the PDP11 stuff. I'm trying to get a
what's called an RA82 drive. It's the
big 14inch monster that spins at 3600
RPM and sounds like a washing machine.
And then I'll find the controller card
and write the code and integrate it into
the driver and try to get that all
Uh, what kind of code are you trying to
run on it?
I'm going to have to get the driver
stack to work. So I have to incorporate
the driver for it into the kernel.
You built a machine recently with one
terabytes of RAM.
Uh how did that happen and why?
So we have a project called GitHub
primes. If you just search for GitHub
primes, you'll find it. And it is primes
a single set of prime number algorithms
implemented in about 100 different
languages. So it's the exact same
algorithm and we require that you follow
certain rules to make it fair
and then you express that algorithm in
whatever language you choose to the best
of your ability and we run a benchmark
every night and we compile the results
and find out which languages are
Is this the one?
Oh, so this is uh so yeah, you got to
and this is what that you're using this
Oh, so this machine runs that those
Okay. You got to tell me about this
project. This is an epic project. So
you're comparing the performance of the
different programming languages
of all these languages. So they all get
built into an individual docker
container and then they all run and
this is an incredible project. This is
really really cool. It's really
measuring the performance of the
different languages. So what what have
you learned about which languages
uh like who which language usually wins?
Zigg I think right now
it does it varies. People will make an
improvement to the C++ and it'll pass
for a while and then the Zig guys will
get angry and come back and make it
faster. ZG, Rust, C++, C.
And what kind of code is being run?
What's the piece of code that they're
trying to run to measure the
performance?
So, what they're doing is they're
solving the primes up to 100 million as
many times per second as they can in a
5-second loop.
So, it's a loop. Got it. Over and over
and over and over and over.
Yeah. On all cores.
So, what
across all CPUs?
What about like how the program is
written? Does that vary?
No. So you can do anything you want, but
it has to be a prime civ. You're allowed
to use one bit per integer at most. So
you can't use a bite, which is cheaper
and easier.
Um there are a number of rules like that
that you have to allocate the memory
within your timed loop. And so we have a
set of rules and we have uh some
solutions that don't follow the rules
like the 6502 because you've only got
64k, you can't do 100 million civ. So
there's a lot of solutions like that
that we run as exhibition projects, but
among the main languages, they all
follow the same rules. And so it really
should just be the how the algorithm is
expressed in that language. And many of
them use the same backend compiler. So
it really is how you're expressing and
the limitations or the benefits of that
Are there allowed to be multiple
submissions per language?
Yep. Yeah. So if you look in the C,
there's like five, I think.
Okay. And they they some of them might
use different compilers or no.
Yeah. Some are GCC, some are C lang
I'm looking at a snapshot here from a
couple years ago. So Zigg was at the
top, then Russ, then Nim, Hasco.
Oh, no. This is not this is not ordered
by uh Slowness, or is it?
So C would be 1.5 times as long as Zigg.
Okay. Fascinating. Well, it's a super
cool project.
Yeah, we've got crazy languages like
PowerShell. There's a version of
PowerShell and stuff like that. So
So this is automated like in terms of
organization of like how the submissions
are done. There's a structure to it.
That's cool.
Yeah. There's two guys over in uh
Europe, Rucker and Tutor basically own
this now. I started as just three
languages. I did Python, C and C++. And
I checked them in and I published the
episode and then people started throwing
more solutions in there and it just got
out of hand. So I had to get somebody to
manage that one and they've been great
doing that for me.
What's the happiest moment for you when
you're programming and building a thing?
Like what do you enjoy most? I think the
the most fun for me is when I build
something complex and I thought through
how it should work and then I run it and
it does work that way.
That creates intense satisfaction.
So seeing the results come out the way
that I plan them and have it work cuz it
rarely does the first time. But
yeah or especially if it does work the
first time. No,
I never trust that. I always feel like
I'm missing something.
That's true. Uh but you know with
compiled languages like um with C++
that's always a good feeling. You write
a bunch of code, you compile and it all
compiles without warnings, without
errors. It's a cool feeling. Um what do
you think is the future of programming?
So now I don't know how much you've got
to really experience the impact of um
LLMs with code generation.
Do you use have you used cursor much
cursor? VS Code with uh with w with with
with code generation.
Yeah, I've done a ton of it for this uh
the Python side because I'm not great
with Python and I'm kind of new to it.
So, um I found it very helpful because
I've learned a lot from watching the
code that it generates if I don't know
how to do something because if I write
Python from scratch, it's going to be
about four times as long as what the AI
can crank out because Python can be
pretty tourist if you're good at it.
Oh, that's cool. So, just you you
essentially learn Python for this
Yeah. So this is a good case study of
like a great programmer in C++ quickly
learning a language.
Yeah, I'm vibe coding my way through it.
I guess
vibe coding your way through it. I that
is a really powerful use case to learn a
language for if you're already a good
programmer to learn either u a new
language or a new a way to approach a
problem by having it generated because
you already you probably understand the
Python code it generates.
Yeah. like without actually looking up
any of the syntax.
Yeah, it's all pretty self-explanatory
once you see it, but you know, creating
it from whole cloth is a little
different. So,
yeah. Uh but you still have to learn how
to program in order to use it in that
Oh, and to read it to know what to tell
it to do next and all that. Yeah, I
don't think you can vibe code yourself
if you're just new and haven't coded.
But if you're a good programmer, AI can
make you incredibly powerful.
What do you think is the future of
programming like 5, 10, 20 years from
now? this whole process. Now, VIP coding
is kind of a fun meme thing because you
still have to be
uh the people that don't know how to
program and are just VIP coding are
almost entirely creating systems that
are not usable in production. They're
not you can't it's very difficult to
create the a product.
Uh and the people who are already great
programmers kind of vibe code just for
in the way that you're doing it. they're
basically it's just a fancy autocomplete
and they end up editing it or it's a way
to learn a new API or or a new language
or a new whatever uh a new specific use
case or maybe a different kind of like a
guey component or something like that
but as they get smarter and smarter we
don't know where the ceiling is that
might change the nature of what it means
to be a programmer so um do you think
about that
I do I think I don't want to say prompt
engineer but I think it's going to be
something like that in the sense that if
you're an architect building a bridge at
some point guys were down there welding
beams together but now you're dragging
things around in AutoCAD and assembling
from big pre free preform sections and I
assume that's what programming will be
like you won't be in there throwing
individual lines of code around you'll
be moving components and interfaces and
describing to the AI what those
interactions should be and letting it
build the components but I think we're
still quite a ways from it being able to
whole cloth generate you can't say give
me a Linux kernel is compatible with
Linux. One day we'll be able to and
it'll crank it out, but we're not there
Does it make you sad that we're climbing
the layers of abstraction so quickly?
So, you somebody that used to do machine
code and then assembly and C and C++
that we're getting to a point where
we're vibe coding with natural language.
Yeah, I kind of came up at a really
fortunate time I think because I had to
come up with the technology over the co
course of 30 or 40 years. So I
understand TTL logic and I can use AI to
write code and I kind of know all the
pieces in between. There certainly are
holes in my knowledge but I think the
only way to have got that level of
knowledge or the completeness of that
picture is to have lived it for that
And it's going to be hard to duplicate
that for people starting now.
What do you think is the meaning of this
whole thing
of uh existence of life of whatever is
going on here?
making cool stuff.
I guess fundamentally what I care about
is being able to make complex things
that are useful to other people, which
leverages my abilities in a way that
allows me to be creative and to create
things that other people can use in a
way that if I was limited to painting or
sculpting or whatever in the classic
arts, I would be hopeless. Um, and so
for me, that's really the meaning of
life. And then maybe you raise a couple
good kids to hand the baton off to.
Yeah. And you've created uh a lot of
cool stuff over your life. Um that
impacted millions probably billions of
people. Uh and now you're inspiring
you're creating cool stuff for everyone
to see on your YouTube and you're
inspiring people in that way. So for
everything you've done in the past and
everything you're doing now, I'm I'm a
big fan. and I'm really grateful for
what you're doing and um grateful that
we got a chance to talk today. Thank
you, brother.
Thank you.
Thanks for listening to this
conversation with Dave Plameumber. To
support this podcast, please check out
our sponsors in the description. And
now, let me leave you with some words
from Bejorn Straup, creator of C++ and
somebody who, by the way, I interviewed
a long, long time ago, episode 48 of the
podcast. He said there are only two
kinds of languages. The ones people
complain about and the ones nobody uses.
Thank you for listening and hope to see
you next time.
← All Summaries
Watch on YouTube