Hello fellow nixers,
What do you do for a living, or have done?

A lot of members work in different fields, some not even in tech-related field. There's quite the diversity of fields. It's good to share or know what others have/had as work experiences if we'd ever want to discuss or ask questions on a related topic with them. It can even inspire others about new fields they'd want to venture in.


NB: Please keep this somehow tech related, don't go too much off-topic, yet if you don't work in tech, still mention it and what you do as it's always interesting to know.

Found a previous thread.

Let's kick this off!

I work in a company that specializes in remotely configuring devices. This is mainly about telecom handsets/sims and routers.
We have components that plug into the network nodes and listen for subscriber's events and upon that trigger actions such as sending them configurations by binary-SMS, or instructions via normal SMS, or others. This can be used to alert inbound or outbound roamers about tariffs for example.
Another thing I've worked on is something called an EIR: Equipment Identity Register. It's basically a big DB that every operator has with the equipment identifiers of the devices on the network that have rules attached to them. This can be used to blacklist/whitelist/greylist devices and take actions upon their detection. Additionally, multiple mobile operators in the same country can sync up these DB with a national one, or with an international one offered by institutions like the GSMA.
Something else I touch frequently are sim cards. We do remote configurations of their file system and settings via OTA, which can either be specially crafter binary-SMS or an HTTPS-PSK server. This last one is rarely used as it infers that the operator has to buy sim cards with this feature, which are way more costly for them on a large scale. To do that we have to study specifications related to security involved, and to integrate with something called an HLR/HSS, which is the name of the telecom node that stores the ID of the subscriber (IMSI) along with their actual phone number (MSISDN) and the encryption keys used to attach to the network.
I've also dealt with creating what's called sim applets for java cards, which are 99% of sims today. These are normal java software but that use a very small subset of the java language (only has bytes, short, and arrays as types), no garbage collection, and very small memory space (non-volatile and volatile). You can install them remotely on the sim without user interaction. The capabilities we use is mostly for interfacing with the device via a set of predefined commands called STK (sim toolkit). That means sending SMS, displaying popup, ringtones, asking for the location of the device or its current equipment ID, and others.
The last big project I worked on is something called eSIM, a sim card embedded in the device, that allows to install multiple profiles on it. We provide a server where they can be downloaded from and customize the sim profile for operators. The "profile" is the identity of the sim, it's kind of like setting up their OS configurations. As this is an accredited solution (sim cards are the same tech as credit card, UICC), the site needs secure procedures like rooms with security cameras, and encryption using an HSM (hardware security module). This is pretty fun to follow up the new specifications and products in this space. There's a lot of applications.

A lot of these projects are interesting because it gets us in touch with big vendors, from Apple, Google, to groups of mobile operators.
I don't deal with the radio frequency though, but we do some debugging with network traces if needed.
Yet, this is all at the "edge" of tech in this space but isn't really translatable into what's "marketable" today for other software engineer positions.

One thing I also partly dealt with is remote management of routers, something called CWMP or TR69.

I also do some frontend from time to time using VueJS. The languages we use the most are Perl, Java, C++, Javascript, and a deprecating PHP codebase.

@venam: Your field sounds super interesting. I can imagine that it’s pretty dull at times (like sifting through the docs of weird standards and protocols), but still. I hardly know anything about any of the topics you mentioned.


I work as a sysadmin in a medium-ish company. I’m an “internal” admin, meaning my team doesn’t deal with customers’ systems directly, but we’re responsible for keeping our own systems (and our infrastructure in general) up and running.

A colleague started the config management system BundleWrap some time ago – around the same time that Ansible started, but Ansible wasn’t usable back then, so we made our own thing. If Ansible would have been more mature back then, we might have ended up using that instead. We like to not write our own software, but it happens alarmingly often that we can’t find a standard solution to our problems. For example, I developed our backup system on top of rsync + ZFS, because none of the alternatives were satisfying.

Anyway, a lot of my work involves writing stuff for BundleWrap. You know, you don’t write an nginx.conf manually anymore, but you have templates for it and abstract representations of your systems. We have one big Git repo where all systems are managed – internal systems and customer systems. So in the end, what I do often affects customer systems after all.

Over time, we have automated a lot of the stuff we do. For example, we use several cloud providers where our VMs run and we have a tiny amount of servers on premise, all of which form a big internal network, all connected over IPsec (or Wireguard, yay!) with BGP for dynamic routing. Pretty much none of that is configured manually. We basically add a new “location” (think “a new office” or “a new cloud provider”), assign it a subnet, and then the config management system takes care of creating the IPsec tunnels, bird configs, monitoring, backups, and so on. All that basically by extending a Python dict (and bootstrapping the actual VMs where this all runs on).

I’m pretty happy that – so far – (almost) all we do is Linux only. My work laptop runs pretty much the same Linux environment that I run at home, including my own window manager, which is pretty cool, I think. When I started at that company, there were still a bunch of Windows servers, which were a total mess and sheer horror, so we did our best to get rid of them. There are one or two Windows VMs left, which we only need because of … guess what? Printer management software.

I sometimes try to push OpenBSD a bit, but nobody other than me knows it and Linux just works, so I’m not very successful. But at least I had some fun with OpenBSD recently while establishing a Wireguard tunnel to a customer who runs OpenBSD – which is insane! We create lots of IPsec tunnels from our network to customers’ networks and most of the other companies use some sort of silly “hardware” firewall, which only provides a web interface and only supports IPsec (sometimes not even IKEv2, let alone good crypto). This almost makes you lose (even more) faith in humanity. Not this time! That guy actually ran a bunch of OpenBSD boxes, so we could figure out the Wireguard config and pf.conf together. I wish that happened more often. :-)

On rare occasions, I make a new web app using Python + Flask. I really try to avoid doing frontend stuff, though – my web apps are usually of the “if it doesn’t work in Lynx, then it’s broken” variety. (Is it even a plural? Did I make more than one web app? I don’t remember.)

Before and during University, I had very different jobs (driving as a courier; something like a janitor; cleaning swimming pools). I miss that sometimes. Simpler times.

These days my title is either Linux Engineer or Linux Consultant, both are basically sysadmin with extra steps.

Since my first Linux job in 2013 I have worked for both large and small companies in various sectors from financial to security.

My current role includes writing Ansible playbooks, monitoring Linux systems both on-prem and in the cloud, patching, and various other "sysadmin" type tasks. Small to medium projects crop up occassionally, like building Hashicorp Vault clusters, or Rancher (Kubernetes) environments for the dev teams. Every now and then a large project will require some Linux knowledge so I will be brought in as a subject matter expert. Previous roles have been similar, with some leaning more towards the DevOps side of things.

While I don't care much for my current companies product (reinsurance) I do quite enjoy this job. The EMEA Linux team consists of myself and my manager, who is very busy with meetings and managing two other teams. This gives me a lot of freedom to play around with how to improve things. Since I started almost two years ago I have brought in the use of Ansible and have been slowly fixing all the "snowflake" servers so things are easier to manage.

Before 2013 I was a Electronic Engineer in the Royal Air Force for almost 10 years. This was mostly ground-to-air radar and communications systems used by Air Traffic Control, with some computer engineer work before it was contracted out to private companies.

(23-12-2021, 07:13 AM)venam Wrote: A lot of members work in different fields, some not even in tech-related field.

This is me. I am a Social Worker and *nix is just a hobby/interest of mine. I have worked in the Social Housing and Homelessness sector for most of my career, and I seem to always gravitate towards roles that have a focus on housing.

Currently I work for a National (Australia) Mental Health oganisation, providing case management support for people with chronic and enduring mental illness who've also experienced homelessness or housing instability in their lives.

I'm always the odd one out in these tech/*nix communities. I have a couple of friends who work in IT but mostly I dont have anyone to discuss my passion for UNIX with.

I have considered a career change or perhaps at least doing some formal education in this feild but I honestly dont see myself being able to make such a deviation now. I also fear that working in tech might kill my interest in it. Besides that, I've got a family to provide for and bills to pay so starting on a base salary in a new feild wouldn't be feasible.

So, while I'll always be the n00b on most tech/nix related forums, to my friends and family I'm Hackerman!

I'm retired -- which probably explains why I often seem to be the only one with time to spend posting here on nixers. (grin)

I already posted my technical bio in my introduction and won't repeat it here to save space.

And pfr/Hackerman, there's no need to feel inferior. As I said in my bio, I've always felt a bit that way myself due to my lack of a CompSci or Engineering degree. But if I learned one thing in my career, it's that no matter how much you know (or think you know), there's always someone who knows more and about cooler things than you do. So stay humble but self-confident, share what you know, and keep learning!

I've told my kids I want to buried with technical manuals and math books so I'll have some reading to do. Trying to grok category theory and functional programming sounds like a nice way to spend the rest of eternity! I'm not the fastest learner but I'm stubborn and can see through brick walls if you give me enough time. Eternity might almost be enough.(another grin)

This sounds like an amazing retirement plan.