How I introduced a 27-year-old computer to the web

December 12th, 2013 165 comments

Reviving an old computer is like restoring a classic car: there’s a thrill from bringing the ancient into the modern world. So it was with my first “real” computer, my Mac Plus, when I decided to bring it forward three decades and introduce it to the modern web.

My Macintosh Plus. Spoiler alert: here it is surfing Wikipedia.

It’s a lowly machine, my Mac. The specs pale in comparison to even my Kindle: 8 MHz CPU, 4 MB RAM, 50 MB hard drive, and 512 x 384 512 x 342 pixel black-and-white screen. My current desktop PC is on the order of 200,000 times faster — not even including the GPU. Still, that Mac Plus was where I cut my computing teeth as a child. It introduced me to C, hard drives, modems, and the internet.

Yes, in a certain sense, my Mac has already been on the internet, first via BBSes and later via Lynx through a dial-up shell sessions. (There’s nothing quite like erotic literature at 2400 bps when you’re 13 years old.) What it never did was run a TCP/IP stack of its own. It was always just a dumb terminal on the ‘net, never a full-fledged member.

How hard could it be to right that wrong?

Everything went smoothly at first. I had my mom ship the computer to me. It arrived in good condition, having been stored undisturbed in her basement since the mid-1990s. I plugged it and its external hard drive in, flipped the power switches, and watched the happy Mac glow to life on the tiny CRT. Sure, the hard drive gave a groan of protest when it first spun up, but that quieted down, and everything seemed stable with the data intact. At least for the first few minutes.

I was far down nostalgia lane playing a game of Glider when all of a sudden there was a loud *POP* and the smell of smoke. Panicked, I slammed the power switches off and pulled the plugs. It didn’t take much sniffing to find the source of the acrid odor: the external hard drive.  The stress of current after years of disuse had proved too much for one of the filter caps in the external drive’s power supply.

A cracked XY cap from the external hard drive’s power supply.

Fortunately, Digikey still sold those exact caps(!), and I’m handy with a soldering iron, so a few days later I was back in business. On to the networking!

To accomplish my goal, I needed a web browser, a TCP/IP stack, and some way to connect the Mac to my home network.

The web browser was relatively easy to find thanks to guys running long-forgotten FTP sites in the dusty corners of the internet. MacWeb 2.0 was both old enough to run on my Plus and new enough to render HTML and speak HTTP. Sort of. But we’ll get to that in a minute.

A whole 4 MB of RAM to play with! Good thing, because MacWeb required 2 MB.

Likewise, MacTCP existed in a version just barely able to run on System 7.0.  It didn’t support niceties like DHCP, but MacWeb was happy to use it, and it installed without problems, so there was the TCP/IP stack.

Getting the Mac physically hooked to the network was a bigger challenge. The Mac Plus didn’t have an Ethernet port, and things like WiFi were years from being invented when it was manufactured. A couple of companies made SCSI-to-Ethernet adapters about 15 years ago, but those were rare and expensive. I thought about the problem for a while, and it occurred to me that I could channel the early days again: I could use the serial port and PPP or SLIP to bridge to the outside world. Like dialup without the modem.

I set up my Raspberry Pi and ran some Cat-5 to it from the router.  Using a level shifter and a variety of old adapters, I managed to get a serial cable working between the Pi and the Mac. That took care of the hardware.

On the software side, I scrounged around and after several failed attempts found a PPP client that would run on the Plus and a super-simple PPP server called SLiRP for the Pi. Documentation for the combination of MacTCP, MacPPP, and SLiRP was, surprisingly, still available.  After a bit of tinkering with the configuration, I was able to get MacTCP to talk to MacPPP, MacPPP to talk to SLiRP, SLiRP to use the Ethernet connection, and so on through my router and out to the internet.  Since serial I/O on the Mac Plus was processor-intensive, throughput was limited to about 19 kbits/s, but 19 was a lot higher than 0.

A Raspberry Pi doing the heavy lifting for the computer that’s tens of thousands of times slower. The mess in the upper right is a level shifter, a null modem, a DB-9 to DB-25 adapter, and a serial cable.

Now, you might be wondering, “Wait, how did you get all of that abandonware on there in the first place?”  Good question! The Mac’s floppy drive was old enough to be fundamentally incompatible with PC drives, and I didn’t have any floppy drives in my modern computers anyway.

I tried going down the avenue of 100 MB ZIP disks, since ZIP drives were made in both USB and SCSI-1 versions. While I did manage to get the Mac to use the ZIP disks (and in fact switched to one for the primary boot drive), and even got my Windows PC reading the HFS formatted disks using some nifty tools, every attempt to move data from the PC to the Plus resulted in nothing but corrupted files on the Zip disk.

That left the serial port. I happened to have an old terminal emulator called Microphone already installed on the Mac. Microphone supported ZMODEM for file transfers, which you’re probably nodding your head about if you remember BBSes. Thus, to transfer files to the Mac, I SFTPed the questionably legal  files I needed from my PC onto the Raspberry Pi, plugged the Pi into the serial port, fired up Microphone on the Mac as a terminal, and launched Minicom on the Pi from the Mac. I nervously struck the keys to initiate a ZMODEM transfer from Minicom, selected the files, and hit enter. Minicom obliged, there was a BEEP! and a “Save incoming file?” dialog popped up on the Mac. Some un-binhexing later, I found myself running new software on my old Plus. Huzzah!

So, with the Raspberry Pi, MacTCP, and MacWeb all in place, it was time to surf the web! Right? Right?!

No. No surfing yet.

The MacWeb developers apparently took a look at the HTTP 1.0 spec, decided, “Who would ever need name-based virtual hosting?” and left out the feature that 99% of the sites on the modern web relied on. No support for virtual hostnames meant you got whatever you saw when you used the server’s IP address alone in the HTTP request, and for most sites, that was jack squat. Oh, and HTTPS, cookies, and CSS hadn’t been invented yet.


I vented about the problems to Tyler, mentioned that I was in for a long stretch of coding to solve it, and was surprised when he whipped up a filtering proxy solution in about 20 minutes using Python, Requests, Flask, and Beautiful Soup.  (Update 12/16: here’s the code from Tyler.) The key to it all was that MacWeb would include the full URL, with the hostname, when making a proxy request.  Requests fetched the URL, stripped SSL and managed any cookies. BeautifulSoup stripped out things that MacWeb couldn’t understand, like CSS, Javascript, images, and DIVs. Flask pulled proxy duties, reading the request and sending the filtered result back to the Mac.

And that, friends, was sufficient to surf the web. It even looked surprisingly decent, almost like a mobile browser:

The Mac Plus Wikipedia page, as viewed on my Mac Plus


Hacker News as viewed by the Mac. Surprisingly readable given that MacWeb doesn’t support CSS

Sure, it was slow as hell, but it worked! Data loaded, pages rendered, and links were clickable. Even forms sort of worked.

Did I mention it was slow? It was slow. Soooo sloooow. Slow slow slow.  Like, minutes to read and render a page slow. Here’s a video showing how slow:

Whatever. The goal was simply to introduce the Mac to the web.

The meet-and-greet was successful.

Epic Race

November 12th, 2013 1 comment

A few weeks ago, I was at Luke’s house when his roommate mentioned a contest: be one of the first to visit all of the ski resorts covered by the Epic Pass this season, and win an Epic Pass for life. I was intrigued.

I mentioned the idea to Tyler to see if he’d be interested in making it happen. We both are fortunate to have flexible schedules, so it seemed at least plausible that we could make a run for the prize. We’d already embarked on a race to be first in line to opening day 2012-13 (and lost), so how much harder could the Epic Race be?

Epic Race: Ski 26 resorts first, get a ski pass for life

We fired up some web browsers to work out the logistics.

The full Epic Pass covered 26 ski resorts spread among 4 countries, including 5 states in the US. We would need to visit each resort, but no earlier than November 22, and no more than one resort per day (in the US), nor more than two per day abroad. Since 12 of the resorts are in the US, with the remaining 14 in Europe, that meant an absolute minimum of 19 days of skiing.

Skiing with friends at A-Basin, one of the Epic Race locations, in May 2013

Further complicating the matter was that not all of the resorts open at the same time. Some had been open since October, others wouldn’t open until mid-December. Not all of the resorts had published opening dates, but history, recent weather patterns, and the resorts’ web sites suggested that openings would be, and I quote, “SOON!”

Here’s how it broke down:

Resort Opening date Location
Vail 11/22/2013 Colorado
Beaver Creek 11/27/2013 Colorado
Breckenridge Open Colorado
Keystone Open Colorado
A-Basin Open Colorado
Eldora 11/22/2013 Colorado
Canyons 11/29/2013 Utah
Heavenly 11/22/2013 California
Northstar 11/22/2013 California
Kirkwood 11/22/2013 California
Afton Alps Soon! Minnesota
Mt. Brighton Soon! Michigan
Verbier 11/30/2013 Switzerland
St Anton 12/6/2013 Austria
Lech 12/6/2013 Austria
Zurs 12/6/2013 Austria
St. Christoph 12/6/2013 Austria
Stuben 12/6/2013 Austria
Courchevel 11/23/2013 France
La Tania 11/23/2013 France
Meribel 11/23/2013 France
Brides-les-Bains 11/23/2013 France
Les Menuires 11/23/2013 France
Saint Martin de BelleVille 11/23/2013 France
Val Thorens 11/23/2013 France
Orelle 11/23/2013 France

Add in a few days for travel, and the minimum time quickly swelled to about three and a half weeks. In order to maximize the odds of winning, the final resort visits needed to be on the first day those resorts were open, which implied that the trek really needed to start as soon as possible. That meant starting on November 22 and doing nothing except skiing and traveling for the better part of a month.

That’s just the cost in time. The cost in terms of money was even more onerous.  Being that we lived in Denver and knew people around Minneapolis, Detroit, and Salt Lake City, we figured we could get away with paying for lodging and transportation just in the Tahoe region and Europe. Still, the cost for flights, hotels/hostels, and cars looked significant. That didn’t even cover the opportunity cost.

We had jobs that could be done remotely from anywhere in the world. We were fortunate in that regard. Unfortunately, the burden of travel meant that only a portion of our usual work output would be likely to get done for the month on the road. Thus, the need to factor in some lost wages.

Here’s a quick accounting of the cost per person, assuming two people went and split relevant expenses:

Item Cost
Flight to/from Europe 1200
Flight to/from Reno (for Tahoe) 200
Flight to/from Minneapolis 200
Flight to/from Detroit 200
Flight to/from Salt Lake City 150
Hostel for 9 nights in Europe 450
Hotel for 3 nights in Tahoe 225
Car for Tahoe, inc. gas 80
Car for Europe, inc. gas 500
Ski rentals everywhere (cheaper than paying to bag-check skis) 400
Lost income 10000
Total $13,605

…or whatever my actual income was :)

And what would we win if we were to accomplish the task first? An Epic Pass every year for the remainder of our lives. With a nominal value of $729 per year, and perhaps 30 years of skiing left, that was a value in nominal dollars of about $22,000. But wait! We’d owe taxes on that, so a better approximation of the value was be more like $13,000.

The expected value got even lower after factoring in the possibility of not being one of the first 10 finishers (thus winning nothing) or considering the potential future value of the money applied towards the expenses.

It would have been a fun trip, and no doubt it would have served as great fodder for stories, but the cost in time and money was too high for the potential payoff.


Are Yahoo Mail users better customers than Gmail users?

September 28th, 2013 Comments off

I admit it: I judge you by your email address. Whenever I see a Hotmail, AOL, or Yahoo address, I can’t help but think that somebody didn’t get the memo in the mid-aughts about moving to Gmail.

It’s ridiculous. Somebody is no better or worse of a person for using Hotmail. All a non-Gmail, non-custom, address probably means is that the person is outside of my peer group. And yet the bias remains.

But what if that bias is justified? What if I can tell how good a customer will be based on the customer’s email address?

I run a µISV, in which I develop and sell blur reduction software called Blurity. As such, I have a large collection of purchase data, and that purchase data contains email addresses.

Let’s start with a look at the distribution of email address domain names. I queried the purchase logs for Blurity from October 2012 to find the percentage of purchases associated with each second-level domain name. Domain names that appeared in less than 1% of purchases were consolidated in an “other” group. From that, we can see that Gmail, Yahoo Mail, and Hotmail are the most popular email services for Blurity customers:

Proportions of email address domains for Blurity customers. Domain names representing less than 1% of customers are grouped in “Other.”

Not surprisingly, people also liked holding on to email addresses more commonly associated with ISPs, such as AOL, Comcast, Verizon, BT, and COX. (Time Warner fell just below the 1% threshold and is part of “other.”)

It’s tempting to say that Yahoo Mail is under-represented among customers, since in terms of US email service market share Yahoo Mail is roughly equal with Gmail. However, the share percentages are about equal for international users of the two services, and I couldn’t split my purchase data on international lines. Dead-end there.

So what can we look at? Maybe something to do with money? Well, how about return rates?

Blurity has a somewhat high return rate. Embarrassingly high. I attribute that to a combination of my poor UI design skills and the general misalignment between public perception of blur removal and the reality of blur removal. That, in turn, is complicated by the fact that many people don’t read directions, which is further compounded by people believing that the purchased version will somehow do better blur removal than the free trial version. As a result, I occasionally get emails asking for refunds. It’s the cost of doing business. I’d rather have a happy former customer than an angry customer.

I’d always felt that refund requests were more likely to come from the group of people using email services associated with lower degrees of technical prowess, such as Hotmail and AOL, so I was a bit surprised when I pulled the actual data. Turned out that the refund rate of Gmail users was not significantly different from that of Hotmail users, nor for Gmail versus AOL users.

Yahoo was a different story. The refund rate for Yahoo Mail users was higher than that for Gmail users at a statistically significant level (chi-squared, p<0.05). Found one!

That's enough data to recover the underlying numbers. Or is it?

Return rate by email domain name.

A higher return rate is nothing to celebrate, but it’s always nice to discover data vindicating one’s intuition.

Overall, Gmail was pretty good, or at least average. The only group that had a non-zero return rate significantly lower than Gmail was the “other” bin (chi-sqaured, p<0.01). The rest of the domains, including Hotmail, were all roughly the same, ignoring a few small-sample-size zero counts.

After seeing those results, I wondered what other predictors for refunds I could find in the data. I suspected that customers paying with PayPal might have higher return rates than those paying with Stripe. Maybe it was a manifestation of the general ill-will towards PayPal in the tech community? Much to my surprise, the refund rate for PayPal is actually lower than for Stripe (6.4% vs. 9.5%), though not significantly so.

I’m not sure that this is very actionable. The vast majority of customers of all sorts, including those with Yahoo email addresses, have been fantastic. I might try an A/B test for users entering Yahoo email addresses, perhaps with a more explicit link to the user manual or a tutorial video. Of course, if I think that might work for Yahoo users, then I might as well try it with everybody. Yahoo might have more refund seekers than other services, but it by no means has a monopoly.

Update: Had another customer make a purchase today and then almost immediately (three minutes later) ask for a refund. The customer’s email service? You guessed it: Yahoo.

Update 2: My friend Luke pointed out that the, Hotmail, and MSN domains are really all just Microsoft services. I agree, they should probably be grouped. I ran the numbers again with that grouping and found that the refund rate for the Microsoft properties does not differ significantly from that of Gmail, and the confidence interval is very similar to that charted for Hotmail alone. Thus, the conclusions above remain unchanged. Regardless, a good catch!

Pulp Entrepreneurship

September 16th, 2013 2 comments

With apologies to Quentin Tarantino.

At a table inside the Coupa Cafe, a coffee shop in Palo Alto,
California.  VINCENT and JULES are eating breakfasts of
eggs/sausage/pancakes and a muffin, respectively, and drinking
coffee.  They are talking about entrepreneurship.

        Yeah, I've just been sitting here thinking.

        About what?

        About the startup I've got cooking.

        Startup in your mind.  I think you don't have anything
        more than a weekend hack.  Maybe a web app at best.

        What is a startup, Vincent?

        A company that's just getting going.

        And what kind of company would qualify?

Vincent takes a sip of coffee

        It's... a company that has aspirations of growth, of making
        money, 	of changing things for the better.

Jules points at Vincent to indicate that he's hit on the main idea.
Vincent pauses, and then continues.

        But your little side project, I don't think it qualifies.


        Hey Vincent, can't you see that shit don't matter?  You're
        judging this shit the wrong way.  I mean, it could be that
        my company will hit it big, or that Snapchat won't just be a
        fad, or that some 16-year-old will flip a stupid vampire
        social network to some dumb 18-year-old wannabe hedge fund
        manager.  You don't judge shit like this based on merit. Now
        whether or not what I'm doing is an according-to-Graham
        "startup" is insignificant.  But what is significant is that
        I feel it in here. 

Jules points to his heart.

        I know that what I'm doing is a startup.  Call it what you
        want, but it's a startup to me.

        But why?

        Well, that's what's fucking with me.  I don't know why.  But
        I know it's what I'm meant to do.

Vincent SCOFFS.

        You're serious?  You're really thinking about quitting?

        Software consulting?  


        Most definitely.

        Fuck. You're making such great money!

Vincent SIGHS.

        So what are you going to do then?

        Well, first I'm going to deliver the remaining code to my
        client.  Then, basically I'm just going to do the startup thing.

        What do you mean, "do the startup thing?"

        You know, like Zuckerberg and Facebook. Raise money, write code,
        change the world.  

        And how long do you intend to "raise money and write code"?

        Until my startup takes off and I have a successful exit.

        And what if you never have an exit?

        We're in a bubble.  Somebody will buy it.

        So you decided to be an asshole. 

        I'll just be Jules, Vincent.  That, and I'll be incredibly
        rich eventually.

        No Jules, you decided to be an asshole.  Just like all of
        those pieces of shit writing pretentious blog posts and
        going on about social-this or mobile-that.  Who pretend
        their MBAs qualify them for eight-figure VC investments,
        or who treat content farming like it's adding utility to the
        web.  They have a name for that, Jules: an asshole.  And
        without a revenue plan or a product that will scale that's 
        all you're going to be at your so-called "startup": a 
        fucking asshole.

        Look, my friend, this is just where you and I differ.

        Jules, what happened over the past few days, I agree,
        some angels showed some interest and your stub of a signup
        page collected a few email addresses, but an actual
        startup?  I don't think...

        Any idea as long as it can get traction, Vincent.

        Don't fucking talk that way to me, man.  How will you make

        If my answers frighten you, then you should cease asking
        scary questions.  

        Let me ask you something; when did you make this decision?

        Just recently.  I was sitting at home, reading about how
        Twitter was about to IPO, and how Uber picked up $250 million 
        from Google, and I had what techies refer to as, "a moment 
        of jealousy."


When robots flew

June 25th, 2013 Comments off

I was getting out of my car when a small plane buzzed over my head. Sam was parked in a grass field amongst many other Subarus and SUVs. The clouds above were breaking; it was going to be a hot day in Boulder.

I let my gaze follow the plane as it buzzed down the field. A wide gate was set in the air like a high-jumper’s bar, but instead of going over it, the plane went below it. In the distance, I could hear a roar of approval come up from the crowd of spectators. It would have been a trivial flight maneuver for a human, but no human was at the controls: the plane was flying autonomously.

When I think of robots, I think of autonomy. Sure, remote-controlled devices may technically qualify as robots, but that’s always seemed a bit like cheating to me. Imagine my thrill, then, when I found out that one of the largest competitions for amateur autonomous robot designers would be held an hour from my home in Denver.

The Autonomous Vehicle Competition draws participants from all over the country, and indeed, the world. It’s the effort of Sparkfun, a Boulder company that supplies electronic parts and kits to hobbyists of the robot kind. The competition is split into two different challenges: one requires navigating a ground course, roughly a square 100 ft on a side in a parking lot with obstacles; the other requires flying from a judging area over about 300 feet of water, crossing a peninsula, and returning to the origin. Each run is scored according to navigation time and extra challenges completed.

A ground-course vehicle leaps over the finish line

About a decade ago, my friend Joey and I made a GPS-guided self-driving Lego car for a class project. It was crude and didn’t work very well, but the thrill of having wrought into existence something that could actually drive itself around — well, I was all smiles even back then. The same enthusiasm was written on the faces of the hobbyists and engineers at the competition. I’m sure the same excitement is shared by those people working on the slightly bigger toys at Stanford and Google.

A large crowd of spectators packed the viewing stands and spilled out along the safety fences and grass. They were young and old, overwhelmingly male but not wholly without female representation. Some were entrants waiting for future heats; others were simply there for a passive thrill.

I spent some timing watching the aerial competition before moving to the ground track. Much to my surprise, the plane I had viewed upon my arrival was one of just a few fixed-wing entries. Though there was one true helicopter in the mix, the vast majority of aerial bots were quad- or octo-copters.

One of many quad-rotor entries; but unlike the others, a successful one

I’ll admit that a certain part of me wanted to see a big splash in the aerial competition, but that didn’t happen: the designs were surprisingly resilient, albeit not often successful. Also, the makers were generally standing by ready to cut over to manual control should everything go sideways.

Some entries ran the course and chalked up bonus points without breaking an electronic sweat; others failed to do much more than lift off the deck, hover for a few seconds, and set back down.

Over at the ground competition, the range of entries was a diverse affair. Everything from self-balancing two-wheeled contraptions the size of a coffee cup to a big-wheel tricycle made attempts on the course.

A “big wheel” is chased by a mini Segway

The course proved deceptively difficult. Very few of the ground vehicles successfully navigated the circuit. For at least half the entries, that meant failing to make the first of the four turns.

Some bots slammed into the far fence. Others turned too soon. A couple spun around at the starting line and zoomed off at high speed the wrong way around the course. The defending champion’s bot got loose in the infield, leading to a college-age nerdy guy running as fast as he could to chase it down, with the bot swerving to and fro as if it were trying desperately to escape some tyrannical master.

Spectators, spectators everywhere

Oh, and crashes! During the unlimited-class heat, I got to see the carnage I had paid (nothing) for: one smallish slammed itself into the far fence. Meanwhile, a large gas-powered go-kart bot gained speed off the starting line, started going for the first turn, and then apparently decided to give it a miss and accelerate into the fence — right where the small bot was hung up! The go-kart tried to get away and dragged the small bot a good 20 feet down the fence, leaving bent wire and miscellaneous bits of expensive plastic in its wake.

Crashes! A go-kart takes out a smaller bot, much to the amusement of the non-owners

During a lull in the competition, I took a walk through the team pit tent. At table after table, teams (and they were teams — I saw almost no solo entries) were hunched over laptops, sifting through telemetry, tweaking code, and mending broken bot bodies. The people were as dedicated as any I’ve seen in any other competition.

A college-age man works on his robot in the pit tent

And yet, the mood remained light. There was an overwhelming air of fun and excitement. Even the entrants whose bots had failed wore big smiles as they carried their creations off the course and developed stories of what went wrong and how the big victory got away. Fishing stories are not just for fishing.

Entries ranged from the simple (an 8-year-old boy made it half-way around the track with a Mindstorms-based four-wheeled bot) to the ultra-sophisticated (the university quad-copter teams running using GPS, computer vision, and other whiz-bang gadgetry). Complexity seemed to be poorly correlated to success, at least on the ground course: the slow and steady bots, apparently using dead-reckoning, generally performed more reliably than their fancier, faster, GPS-enabled, optical-sensor-encrusted cousins.

This young girl’s robot had no shortage of anthropomorphic flare

I felt more inspired than ever to make an entry for next year. How hard could it be?