Yotam's blog

How Can I Learn While Using AI?

me@yotam.net (Yotam Nachum) — Sat, 01 Aug 2026 14:56:00 +0300

Recently I had a problem with my sound in Linux. Although Linux desktop had progressed immensely in the last several years, still sometimes I find myself trying to understand what went wrong. This time, instead of diving into the system logs, I let an LLM model do it. Quickly I got the root cause and a solution which was to turn off the unnecessary Pipewire plugin. That led me to a sad realization.

Piercing the Shadow Root Using CDP

me@yotam.net (Yotam Nachum) — Sat, 13 Sep 2025 14:28:17 +0300

Part of my day job is orchestrating browsers using the Chrome DevTools Protocol, also known as CDP. CDP is a powerful protocol that exposes many ways to control and inspect a running Chrome instance. People usually interact with a wrapper around CDP like Puppeteer or Playwright but sometimes to get the full power of the protocol, you need to use it directly. Sadly it seems that the protocol was not properly designed and everything was bolted on as the protocol expanded to expose new functionality.

My First FOSDEM

me@yotam.net (Yotam Nachum) — Tue, 04 Feb 2025 22:12:00 +0200

I’ve wanted to attend FOSDEM for the last few years, and I finally made it this year for my first time. I came with two friends from my previous job and it was a blast. I’ve read beforehand whatever I could about the conference but it still took the first day to understand how to get around the conference.

Talks

Each of us made a list of talks we wanted to attend. Of course there were overlapping talks but we were ready for that. I’ve also read to not overdo the talks since it’s very tiring. Still the first talk we tried to attend was full with no chance of getting in. We cut our losses and went to the stands which were great although also a bit crowded.

Remote Reverse Tethering With Gnirehtet

me@yotam.net (Yotam Nachum) — Sat, 27 Jul 2024 19:12:00 +0300

Recently I had some automation work again with Android but this time with a catch, it had to work with remote physical devices that are not reachable over TCP. More than that, I wanted to connect my devices to a VLAN that I assemble and dismantle on demand. I’ve done something similar to it before with Gnirehtet¹ for reverse tethering into the VLAN but this was the first time using a remote ADB server.

Dont Forget The Dot

me@yotam.net (Yotam Nachum) — Sat, 25 Nov 2023 19:02:32 +0200

Recently we discovered a surprising bottleneck in our Kubernetes cluster at work. Apparently, our DNS server was overloaded and started to respond slowly. We have applied the quick solution suggested by Wolt’s excellent post but it was only a superficial solution to the bigger problem, why do we have so many DNS queries?

The reason for the DNS load was for two reasons:

DNS records in Kubernetes have a low TTL by default. While you can change it, it does have it’s own drawbacks that should be considered.
For each DNS query we actually sent two, one after the other. When trying to reach example.com for example, we will first query example.com.svc.cluster.local and only then will try the actual domain we wanted. The reason is that Kubernetes will first lookup to see if the requested DNS is an internal service before trying to reach out to an external DNS server. That would also apply to local services, before querying internal.svc.cluster.local it will first query internal.svc.cluster.local.svc.cluster.local.

The Solution

The solution was actually one character long! A fqdn must actually contain a dot at the end of it to represent the root DNS. So instead of querying example.com we just changed to example.com.. The root DNS suffix mean that it can’t be a local service because you can’t append anything after the last dot.

Please, Let Me Choose The Binding Address

me@yotam.net (Yotam Nachum) — Sat, 28 Oct 2023 21:17:56 +0300

When a program is listening for new TCP connections, it needs to choose which ip address and port to listen on. While the port option is pretty easy to understand¹, people give less thought to the address they use. Why is that?

Usually programs bind to one of two addresses: 127.0.0.1 to listen on the loopback interface or 0.0.0.0 to listen on all interfaces. While those are the most common options, some people have more complex setup that won’t fall in one of those two options. For example, Google Chrome will only let you expose its CDP port to the loopback interface, which make sense for most people but not if you want to expose it remotely. The other option is also not always nice to have. Beside security risks of listening on all interfaces, sometimes you might have different interfaces for different services and listening on 0.0.0.0 will cause a port collision.

OpenBSD in an Air-Gapped System

me@yotam.net (Yotam Nachum) — Sat, 12 Aug 2023 15:08:54 +0300

Recently I had the displeasure of working again within an air-gapped system. The main obstacle I usually have with these systems is that it’s very easy to mirror a complete packages repository but a lot harder to mirror only a specific set of packages and their dependencies. About a year ago I had to figure out how to do it with OpenBSD, but recently I had to do it again and completely forgot how to do it. So in order to not make the same mistake twice, here is how to do it properly with OpenBSD.

Network Management in Android: Routing

me@yotam.net (Yotam Nachum) — Fri, 07 Jul 2023 22:14:01 +0300

I plan on diving deep into Android in future blog posts but for now I thought I might share something that was really confusing to me in hope to prevent the confusion to others. The confusion was not actually Android exclusive, I just stumpled upon it while working with Android and it was a great reminder that routing is a lot more complicated than I usually think of it.

Anyway, if you have an Android machine (in my case a container), you can run ip-route(8) and see that there is probably only one route and it’s not the default gateway. This is because, at least in my Android container, Android doesn’t use the main table for routing configuration. Linux routing actually have multiple routing tables which the kernel looks at for each packet. We can see the rules that decide which table to look at through ip-rule(8). The rule list in my Android container looks like so:

Dedicated CPU instances on the cloud

me@yotam.net (Yotam Nachum) — Sun, 18 Jun 2023 21:00:03 +0300

The cloud is notoriously expensive compared to the comparative on-prem hardware available in the market¹. Of course, the cloud is not only about cost, but also about ease of use and available features like managed databases and security services. Yet, sometimes all you need is a simple, powerful Linux machine. Luckily, there is a large list of options outside of the big three cloud provides that compete mostly on pricing (although some of them have a respectable services catalog).

Compiling Frida on Fedora

me@yotam.net (Yotam Nachum) — Wed, 08 Feb 2023 19:52:16 +0200

Compiling Frida can seem to be a bit daunting, with over two thousand lines of Makefile, and that is without even beginning to look at the shell scripts in there. This complexity is there for a reason, Frida needs to be run on over a dozen of build targets, many of which are not proper building environments. The make files you are looking at are mostly for this reason¹. But luckily, Frida itself use Meson, a modern, sane build system, for the actual building. Not only that, but Frida vendor all of its dependencies with a Meson version to simplify building it even further!

Easing Deployment Without Containers

me@yotam.net (Yotam Nachum) — Tue, 13 Dec 2022 19:21:14 +0200

In the modern world of Docker and Podman, it seems that deployment is a solved problem. But this is only true if you give up on keeping it simple. There are of course use cases for containers, but sometimes all we need is a small Linux VM to run a few services on, why is it so hard?

Recently I’ve tried with varying degrees of success to run several web services, mostly written in dynamic languages like PHP or Ruby on my server. The experience was horrendous, with lots of weird errors and moving parts that I couldn’t understand. I’m not an expert DevOps administrator but I’ve had my fair share of server administration, at work and at home, so why is it still that hard to set up a new service?

Kodi Setup: Sailing The High Seas

me@yotam.net (Yotam Nachum) — Thu, 01 Dec 2022 22:31:34 +0200

I’m not as radical as I used to be and so I do have a Netflix account¹. There are still many shows and movies that I can’t access legally without paying up for yet another media streaming service. Of course, a mere DRM won’t prevent me from watching the latest seasonal anime or another random pop culture show. I’m sure there will be some misguided people saying how I’m stealing other people’s work but I will defer this debate for another time.

Two Different Outlooks of Computers

me@yotam.net (Yotam Nachum) — Mon, 21 Nov 2022 12:31:00 +0200

For a long time by now, I had a conflicting view of my ideal computer system. On the one hand, I strive for minimal, clean abstractions, without the legacy code plaguing most modern software. On the other hand, modern software gives me a huge boost in creativity and makes software more approachable than ever. This contrast between modern software that is focused on productivity and conservative software that is focused on beauty sadly prevents me from enjoying computers.

Linux Namespaces Are a Poor Man's Plan 9 Namespaces

me@yotam.net (Yotam Nachum) — Sat, 05 Nov 2022 10:15:12 +0300

Plan 9 is the failed¹ successor to Unix. It was developed by the same group, Bell Labs, with all of the experience they had gather in the twenty years since Unix was first written. Many features that are common today in many Unix systems, and some non Unix systems, came originally from Plan 9. For example, the /proc file system was first implemented in UNIX 8th Edition, which was the predecessor to Plan 9². Another example, which I will talk about in this post, is the use of process namespaces.

What Makes Sourcehut CI So Good

me@yotam.net (Yotam Nachum) — Mon, 24 Oct 2022 17:57:09 +0300

I’m not in any way an expert in CI systems, I’ve only used four such systems in my whole career: Jenkins, Gitlab CI, Sourcehut Builds and recently also Github Actions. I’ve been praising Sourcehut Builds to my coworkers for a long time but I always assumed that it’s not that special, just that I had a bad experience with Gitlab CI and Jenkins. That is, until I tried Github Actions and started to appreciate Sourcehut Builds even more.

Promoting Free Culture With Proprietary Software

me@yotam.net (Yotam Nachum) — Mon, 26 Sep 2022 11:44:06 +0300

In the last couple of years I sadly tuned down my free software usage and evangelism. I still believe in it but I just got tired of using 100% free software and decided to take a more pragmatic route. The pragmatic route, just as the title says, it means sometimes using proprietary software. But I’m not talking about Google services or Windows, I’m talking about companies that promote free culture¹ even if their core product is not necessarily free.

The Audacity of Piping Curl to Bash

me@yotam.net (Yotam Nachum) — Sat, 25 Sep 2021 10:50:58 +0300

It seems more and more common, at least in the self-hosted community, to provide two methods of installations: Docker or a shell script installer. It seems that many new projects don’t even bother with a native package manager, such as dpkg or rpm, which makes me reluctant to use them.

Many talk about the security implications of piping curl into bash but it has been talked about enough and the solution is usually splitting the process into two steps, fetching the file and then running it. But what really makes me avoid running those scripts is how complicated they are and their audacity of how they treat my system.

Reviewing my tweaks for Fedora

me@yotam.net (Yotam Nachum) — Fri, 08 May 2020 21:39:31 +0300

I have been using Fedora for a few years now and installed it countless times because it bothers me to have a messy system. I stay on Fedora because it has one of the best out of the box experience, at least for me. But still, there are some things that I need to tweak on every new installation so I have a script to do most of those things and after over four years it got pretty good in doing it. So here are the tweaks that are relevant to Fedora (some configurations like Vim and Tmux deserve a separate post).

Change New Tab in Firefox

me@yotam.net (Yotam Nachum) — Tue, 24 Dec 2019 18:43:16 +0200

I’ve started ricing my workstation again and wanted to change the new tab page in Firefox. Apparently it’s harder than it should be because extensions don’t have access to an API that can do it. You might remember a setting called “New Tabs” but it only let you choose between a blank page and the default new tab page.

Anyway, the solution is to edit the internal new tab service through the browser console. If you don’t want to run the script every time you launch Firefox you can configure it to auto run with an autoconfig.js file.

Why I Give Up on Free Software Phones

me@yotam.net (Yotam Nachum) — Sat, 09 Nov 2019 15:36:11 +0300

For over a year I have used a Google-free smart phone, at first with just LineageOS and later with LineageOS+MicroG. It was a nice experiment but my phone was causing too much trouble and in the end I got fed up and bought a new phone (Samsung Galaxy S10e). I hope one day to have a free phone again (maybe if the Librem 5 will succeed) but currently there isn’t a real alternative that is worth the sacrifice.

Building a Python Project With Meson

me@yotam.net (Yotam Nachum) — Fri, 30 Aug 2019 17:42:12 +0300

I have already shown how to build a Vala program with Meson. In this post, I will show how to do the same for Python. You don’t really need to compile an interpreted language but Meson helps you to put the files in their correct installation directory.

Spawning a Subprocess With GLib and Gio

me@yotam.net (Yotam Nachum) — Fri, 02 Aug 2019 22:16:20 +0300

While I was working on my first GNOME application which I hope to publish soon I stumbled upon a small hindrance of how to spawn a subprocess efficiency without blocking the main thread. I could have left it as is with the straightforward pythonic way but I wanted the user interface to be fluid.

Why Static Typing

me@yotam.net (Yotam Nachum) — Sat, 25 May 2019 11:08:45 +0300

The case of static vs dynamic typing is a long lasting debate without a clear answer. A few years ago it seems that all of the popular programming languages were dynamic: Ruby¹, JavaScript², Python³ etc but all of the languages I have listed have some sort of static typing added to them. Why is that?

Python Type Hinting - Part I

me@yotam.net (Yotam Nachum) — Sat, 27 Apr 2019 13:35:17 +0300

If you are using a recent version of Python (which you should because Python 2 will be EOL in less than a year) than you can use type hinting with a sane syntax instead of using docstrings to document the arguments types.

Compile Vala With Meson

me@yotam.net (Yotam Nachum) — Wed, 09 Aug 2017 16:23:34 +0300

In my previous post Getting Started With Vala I showed you how to write a program in Vala and compile it using valac. Compiling with valac was okay but even with only GTK+ as our dependency the command is starting to get long. If you don’t want to specify all the compiler flags each time you can use a build system.

Getting Started With Vala

me@yotam.net (Yotam Nachum) — Tue, 08 Aug 2017 18:32:00 +0300

Vala is an object oriented programming language that was designed specifically for GTK+ and GNOME development. Vala’s syntax is similar to C# but it compile to C code using the GObject system which let you use the GNOME ecosystem easily.

My Setup

me@yotam.net (Yotam Nachum) — Mon, 01 Jan 0001 00:00:00 +0000

My setup is a bit fluid but there are some workflows that I’ve found to work for me. I will try to focus on what works for me in the long term, a sort of living copy of my post about my Fedora tweaks.

Hardware

I sometimes work from the office but I have little say in the hardware there so I will focus on what I have at home. I do work most days from home so it’s the better working environment for me anyway.