Why I Won't Give You My Phone Number

Oct 15, 2018

If you know me, chances are that you asked me for my phone number and I hesitated. Unless we are really, really good friends you probably didn’t get it 1.


Robocalls. In other words: telephone spam.

Phones, unlike e.g. email, don’t have a spam filter. It’s also very easy for telemarketers to spoof phone numbers. Most call blocking apps, such as TrueCaller, are totally worthless when you get calls from a fresh and completely random number each and every time.

This means that I’m extremely careful giving away my phone number.

In today’s world everyone is using a smartphone. Unless you are a Luddite, you’ll probably have “harmless” apps such as WhatsApp installed on it.

These apps work by uploading your phone’s address book to a server and matching contacts using their phone numbers.

The real problem is all the other crap you might have installed on your phone which is uploading the address book to random chinese servers. That address book has my phone number in it.

Guess how my number ended up on that telemarketer’s list? Most likely it was your phone, your poor taste for apps and your knack for clicking “Allow” everywhere. Yup.

Giving away your phone number these days is like writing it on a public toilet’s wall.

  1. If you got my number, and we aren’t good friends, you probably got a dedicated phone number that is active only when I’m expecting your call, or a completely fake one that I’m sure won’t disturb anyone. 

Get Windows 10 product key without the sticker

Sep 27, 2018

Ever since Windows 8, Microsoft stopped putting stickers with the Windows product key on laptops. They would become illegible with time and they were cumbersome to type when (re)installing Windows.

Where is the product key, then?

It’s “burned” into your laptop’s firmware, inside the MSDM ACPI table.

Thankfully, extracting they is relatively easy if you happen to have a Linux on a USB stick lying around.

You can read the contents of the MSDM table by opening the /sys/firmware/acpi/tables/MSDM file with hexdump. It usually begins with some garbage data whose purpose I blissfully ignore and should end with your product key.

Now you can choose to wipe the Windows partition and virtualize it instead of dual booting. Bingo!

Here’s an example, with my data carefully redacted since I’m not in the business of giving away free Windows licenses (G stands for “garbage”, P for “product key”):

root@cogito:~# hexdump -C /sys/firmware/acpi/tables/MSDM
00000000  47 47 47 47 47 47 47 47  47 47 47 47 47 47 47 47  |GGGGGGGGGGGGGGGG|
00000010  47 47 47 47 47 47 47 47  47 47 47 47 47 47 47 47  |GGGGGGGGGGGGGGGG|
00000020  47 00 00 00 47 00 00 00  00 00 00 00 47 00 00 00  |G...G.......G...|
00000030  00 00 00 00 47 00 00 00  50 50 50 50 50 2d 50 50  |....G...PPPPP-PP|
00000040  50 50 50 2d 50 50 50 50  50 2d 50 50 50 50 50 2d  |PPP-PPPPP-PPPPP-|
00000050  50 50 50 50 50                                    |PPPPP|

ThinkPad T480

Jul 28, 2018

I recently received a new work laptop. We needed one equipped with a touch screen for a particular project. Based on a colleague’s recommendation and an intriguing spec sheet we settled on a Lenovo ThinkPad T480.

It arrived suspended inside a recyclable cardboard box. Inside that box there was another cardboard box with the battery and a USB-C charger. That’s it.

The box

Lenovo's slogan For those who do

Lenovo is conveying a clear message with this thing: we don’t have time for bullshit like fancy packaging. This laptop was made for those who do. You are supposed to have the box dropped on your desk, open it, and start working immediately.

While I appreciate having a nice unboxing experience, such as those offered by Apple and Dell, I also fully respect Lenovo’s no-frills approach. It’s eco-friendly and leaves less garbage lying around the office. Ten points to Gryffindor.

This machine is super configurable. Want 16 GBs of RAM? 32? Want one RAM stick? Two? Want a second hard drive? What about choosing between a TN, IPS, touch or WQHD display? Having choice is nice, even though it’s a bit ridiculous to have so many especially when we are talking about 17€ options like the backlit keyboard.

This laptop has a wicked cool “bridge battery” system. It comes with a fixed internal 24 Wh battery and a slot where you can place a removable one. This allows you to hot-swap the battery while the system is running.

Lenovo images this portable machine with a clean copy of Windows 10 Pro. Only a driver utility and wallpaper were installed. I applaud Lenovo for this tasteful choice. Microsoft ships a lot of bloatware with Windows already, we don’t need any more of it. 1

The keyboard is… fine. It feels a little bit mushier than my MacBook’s, but it gets the job done. I’m totally unable to use the TrackPoint though: it immediately triggers a pain spike in my wrist whenever I use it, in a way that resembles RSI.

The touchpad is, again, fine. It gets a little better when used under Windows 10 with its “Precision Touchpad” drivers but it’s still miles behind the one found on any MacBook built in the last ten years. After all this time, Apple is still the undisputed leader when it comes to touchpad quality and feel. 2

The screen is a 1920x1080 matte IPS panel with 10 fingers multi-touch capabilities. It’s a bit dim (250-270 nits), especially under direct sunlight. It also lacks an ambient light sensor to automatically adjust brightness and contrast. The sensor is especially useful for traveling on the train, since lightning conditions change wildly during a ride. Needless to say, the MacBook has both a brighter screen (320 nits) and a light sensor. Only now I realize how much I relied on that feature.

One pretty big downside of this laptop is its fan. It’s constantly whirring even when the laptop is idle. It’s noisy. Again, this is in stark contrast with my MacBook, which is dead-silent even when compiling Qt inside a Windows VM. The noise can’t be heard in the typical office environment, but it’s annoyingly present when I’m working from home, which is most of the time since I’m remote.

All in all, I like this laptop and its straight-to-business approach. I like how Lenovo refined the traditional “ThinkPad shape” while keeping it true to its origins rooted in the early nineties.

This machine emanates a certain kind of business-y and enterprise-y vibe that’s hard to convey with words alone. Nothing sends a stronger signal that you are doing important stuff than typing on a ThinkPad.

It’s even better if you do it while wearing a suit.

  1. Of course I wiped the laptop clean to dual boot Ubuntu and Windows 10 about thirty seconds after booting it for the first time. 

  2. Moving the cursor with the index finger while having the thumb resting on the surface became possible only with Windows 10 updates released in the last year.