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A whisky tester in the mail

“Reality is a thing for people with a fear of unicorns.”

A good friend sent me a set of small testers with Whisky. A Laphroaig Cardeas 2016, Madeira Cask, a Starlight XXI Sierra Delta, and an Akashi.

The testers made it to me unharmed, wrapped like Sushi Rolls, but the caps unscrewed marginally through the transport vibration. Nothing much was lost, but I now know why the Whisky Calendar is sold with the caps in sealing wax.


Seven Versions of No Backup

When you configure a modern Android, it turns on Backup by Default.

Android 7 or 8, like their predecessors for some time now, offer you to make a backup. The config setup looks somewhat like above, and that’s seems to be quite good. It certainly looks like something you’d want.

Now, it’s 2018, and we all do have multple Android devices on the same account. So if you are using, say, a 5X, and it dies bootlooping, you’d might be tempted to revive an older device for a few days, until the replacement arrives.

Then this happens:


BQ Aquaris X pro

Last weekend my Nexus 5X did the Boot Loop Thing (Article in German, refund only for US customers).

So I needed a new device, quickly. I am certainly not spending 1K Euro on hardware, so I was looking for a Nexus 5X priced device that does not suck.

Harald recommended I am looking at, a spanish company that makes 3D printers, and smartphones, and indeed the X pro delivers. 5X sized, the device can do dual-SIM or SIM+SD, has up to 128 GB memory (I got the 64 GB model), a decent camera and a close to stock Android with a bi-monthly update cycle. Android 7.1.1 with a late 2017 patchlevel in my code. Less than 300 EUR, performs as advertised.

Oh, and the selfie frontside flash is Men-in-Black level weird.



Today I was looking for a way to subscribe to file changes in a directory in MacOS, in order to trigger automatically running commands whenever files change.

Turns out Homebrew has “fswatch”, which tells you when things change, but little else.

Turns out Homebrew has “watchman”, which does all this, and on multiple trees, finds changes across restarts and automatically manages a set of commands for different file endings.

Also turns out that I know the author. Thanks, Wez!

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Swap and Memory Pressure: How Developers think to how Operations people think

There is a very useful and interesting article by Chris Down: “In defence of swap: common misconceptions“. Chris explains what Swap is, and how it provides a backing store of anonymous pages as opposed to the actual code files, which provide backing store for file based pages.

I have no problem with the information and background knowledge he provides. This is correct and useful stuff, and I even learned a thing about what cgroups can do for me.

I do have a problem with some attitudes here. They are coming from a developers or desktop perspective, and they are not useful in a data center. At least not in mine. :-)

Chris writes:


Knock, Knock

What does your Mac do on Startup? Knockknock knows.

It’s not properly updated for current versions of MacOS, but it is still useful. “git clone” and “/usr/bin/python” is sufficient to test.


That’s quite a bit. Apparently, I am starting


Conway’s Law

Melvin Conway is a compiler developer and systems designer, who is well known for the eponymous Conway’s Law. Various phrasings exist of that, and one popular is

Organizations which design systems are constrained to produce designs which are copies of the communication structures of these organizations.

The original paper and an introductory paragraph can be found on his website. It’s worth reading, because there are more useful insights to be found in the original writeup.

So what does this even mean? Can you give examples from your current or previous work environments?

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Plex and TLS vs. beA and failure

Filippo Valsorda wrote an article “How Plex is doing https for all its users” two years ago. In the article, Filippo explains how the self-hosted media server Plex can offer TLS to secure all connections, including those to the user’s servers.

Plex is a server software running on your machine, and a discovery service somewhere out on the internet. Using your login, you connect to the discovery service, and then connects directly to your server, using XHR.

The XHR part means you are on a page, and because that is a https page, the XHRs also need to be encrypted and trusted. That means your server needs to be able to do https, and that means your server needs to have a valid certificate to do this.

How does your server get this cert?