What the hell just happened

It’s been a long year for all of us. As someone who used to take pride and satisfaction in writing about their work on the internet, I look back at the void I’ve produced with mixed feelings. On the one hand, I’ve achieved several goals at work, but haven’t had been able to write about it publicly. On the other hand, the things I did for myself have been so reduced in scope to things that only find useful that I have doubted this whole year that anyone would be interested in reading – including future me! In general, it has been a year of internalisation and self-reflection, given what has just happened to the planet, so I am not all that surprised this subdued desire to write about technical work. I have found myself less able to agree with the sentiment that anything I write on the internet is worth reading, since it always seems so trivial as soon as I see it written down, as if it were a waste of everyone’s time. I’ve found myself jotting down thoughts and immediately deleting them, with a slight admonishment echoing in subconscious: “Nobody needs to hear this crap”.

On the other hand, I have two diaries full of daily notes and journal entries from the last years, so something wants to come out.

I do like to write. As with most of the physical ones in my body, the writing muscle hasn’t been exercised much in plague times, and it feels like it’s starting to atrophy – as I can even now tell from the quality of this post. So, even though I have nothing of greater interest to share, I return here to write something be it solely for the pure sake of exercise.

Home sweet home

It’s always brave to make predictions about the next few posts one plans to write. “This is the first in a series of posts about what I’ve done with my Raspberry Pis”, the first would optimistically open, but it would take just a few moments for history to tell you that the next post in this touted “series” would come more than a few months down the line and start something like “Yeah, this was supposed to be about my Pis, but I have something else on my mind now.”

Consider this a premature apology then, for future negligence, for I do indeed have a series in mind, about what I have done and what I plan to do with my Pis.

Before continuing though, it’s worth taking another look at my changed situation. In the past I have always exclusively used public infrastructure and shared resources, building things for others and in general for community use. Whether this was working in a large collaboration during my time as a grad student or postdoc physicist in Phobos or ALICE, or co-ordinator during my time at the CSIR building the distributed computing infrastructure, the considerations on what tools and methods were appropriate were always generalist in approach.

Now, however, I work in the private sphere, both at work and at home; this is more about what I want. It feels almost rude to be writing with such a personal view! While it’s one thing to express one’s opinion and position on a matter, I find it strangely trivial and selfish to simply write “I want to do this particular thing”. “Who cares?”, I can hear the internet respond – not out of some perceived impostor syndrome on my part, but out of genuine lack of interest on that of the world.

Again, I proffer my apologies, internet. There is nothing of interest here for you. This is purely mine now.

A plural of Pis

“Revenons a nos moutons”

I have a home office now, that has seen my persistent, constant presence because of the pandemic. For the greater part of 2020, I spent almost every waking hour in it. Now, along with the change in scope of the job when I left EGI came an increase in what one might call “personal time”. I was determined to start filling this time with activities that stimulated my mind and body – woodworking, writing, learning the guitar. One of this activities was technological tinkering.

I started trying to learn new languages, or improve my fluency in those I could barely converse in, in particular Go. However, working solely in software seemed somehow to be just not enough, I wanted something that forced me to actually touch things that weren’t a keyboard with my actual hands. I wanted a tactile as well as a mental experience.

And so it came to be that I started a collection of Raspberry Pis.

Pi Three the First

It started with a single Raspberry Pi 3 kit - case, power, the whole basic deal. After booting it and putting it on the network I got that little thrill when a new machine comes up. You know, the feeling of “hey, I made this!”, but of course that was immediately followed by “OK, now what?”.

I have a frikkin Ph.D. in the frikkin nuclear physics, I have no right to feel any sort of achievement for starting a single board computer in my home office! But this was my silly little computer and I did feel a silly little fuzz of accomplishment.

Moving on, I decided to put the poor thing to work by putting PiHole on it. This worked quite well until it started interfering with the work VPN, and became a bit too unstable to reliably leave on.

Pi 4 the Sensening

The few months subsequent to that first experience saw little change, but there was a nagging refrain in my brain, reminding me that I wanted a tactile experience. I wanted things I could hold in my hand, touch, move around and through the world. My attention alit on the SenseHAT and “Yes!”, I thought, “this thing has actual sensors!”. I bought one and a Raspberry Pi 4 to power it.

This was more like it! Data! The environment! I could even use it to show the kids how to pull the real world into the simulated one by measuring temperature, humidity, orientation, etc and making the LED matrix light up in response to changes to the physical world.

The Pi4 and Sense HAT combo is probably what got me really hooked on a Pi garden in my office. I started using it as a visual Pomodoro timer. There is a physical toggle switch to start, pause and reset the timer. Furthermore, it’s an actual physical, three-dimensional thing that occupies actual three-dimensional space in my office, not just a rendering of an idea on a screen that I’m persistently staring into. At one point, I had it hooked up to speakers, over on the other side of my office so that I had to actually get up and take a few steps when the timer ended, better enforcing the principles behind the method.

So, now there were two.

Lots of little things

This setup felt good, but lost a bit of momentum. I started browsing the reseller websites, especially Pimoroni. What else was out there? I started wondering if I could start making things by combining a few components. Of course, one could make things - there are plenty of kits on sale for making little electronic projects - but could I make something. Like, with a soldering iron? The last time I had soldered anything at all was in second year physics and I really had no idea what I was doing.

I realised though that the only voice telling me that this was a stupid idea was that one in my head, and that dude can be a dick sometimes. It still felt strange to justify something like this to myself simply by retorting “because I want to”, but that is what I did.

I went out and bought a soldering iron, then shipped a few Pi-Zeros, batteries, solar panels, LED strips and other fun stuff like Scroll HATs to myself.

Oh and another Raspberry Pi 3 with an e-Ink HAT for good measure.

Now there were 6 little computers of varying power and pose in my cosy office!

As I came to gaze upon them, that curious illusion came to occur where instead of a set of individual items I came to see them as the system they could be. I came to wonder: “What can I do with these as a whole”?

Actual tools for actual fools

So it is that we come back to the start of the next level in our strange loop - making actual use of these things for myself. At the risk of missing some context, I will simply state that we use a good portion of the Hashicorp stable at work. I touch Packer and Terraform code every day to maintain and provision cloud infrastructure and assets, and use Vault to secure the secrets on it.

Hashicorp’s products have an ergonomic polish to them which makes them almost irresistible to use. The documentation, tutorials and guides seem to understand just what one means to achieve and in plain language seem to pull you towards those goals. With this attitude, I’ve been a bit sad that I didn’t have a better understanding of the other products in their catalogue, in particular Consul. Nomad too intrigued me, but I just couldn’t see what they were for. When Waypoint and Boundary came out this year, I watched eagerly and jumped right in with their demonstration uses, but I still couldn’t seem to clear the fog in my mind that lay between the description of these things and what they were actually useful for.

That is, until I started needing some sort of method for organising, accessing and delivering applications to my Pi garden…

When I reached that higher-level concept of “system”, I started to see the need for Consul.

Nomad and Waypoint are next on my radar – but since I’ve just managed to get Consul deployed on my Pis, I wanted to stop here and take stock.


There is a nice symbiosis between work and private life, technologically speaking. I have had to extend my knowledge of them, push them to see to what extent they are useful in certain situations, what their true design was meant to be, rather than simply rely on lazy habits I’ve formed over the years. As a side note, this is true also for the actual hardware tools in my office – the rotary tool, the saws, the soldering iron, the screwdrivers, the chisels and the pincers. These are all made to be used in a certain way; when actually used as intended, it is something akin to a sublime pleasure to feel them achieve what that intent.

Having a little private workshop to try these things out in is, I find, very useful in honing my skill and is both personally and professionally satisfying.