---
title: "Talks"
description: "Motiejus Jakštys on stage"
---

I have done a handful of conference/workshop/meetup talks over the years. Here
are a few.

<hr/>

2025-09-11 DevOpsDays Vilnius
------------------------------

**The Filesystem Diaries: Scaling Btrfs in an Enterprise**

Btrfs was merged into the Linux kernel in 2009, arriving with bold
promises—and, let's be honest, a reputation for instability. I first tried it
on my laptop in 2011. It wiped my data. Twice. On the bright side, it taught me
the value of backups.

Fast forward to 2025: btrfs is no longer the experimental filesystem of the
past. It's stable, mature, feature-rich, and fully part of the Linux kernel.
But old reputations die hard. Even today, Google Cloud Platform doesn’t
officially support it—not because of technical shortcomings, but because
customer demand hasn’t pushed the issue.

At Chronosphere, we decided to take a fresh look. After months of evaluation
and testing, we migrated petabytes of customer data across thousands of disks
to btrfs. This talk is our story: why we made the leap, what we learned along
the way, and how we’re helping bring btrfs into wider enterprise
adoption—including working with Google to support it natively.

I'll share the decision-making process, key performance and reliability
insights, and the quirks you only discover when running btrfs at scale. Whether
you're btrfs-curious or just love a good ops tale, you'll walk away with
real-world takeaways—and maybe a newfound respect for this once-maligned
filesystem.

If you know what NTFS, ext4, or ZFS are, you’re ready for this journey.

No video, no slides.

<hr/>

2024-05-17 Zig Milan Party
--------------------------

**Maps and Yellow Pages**

If you look back 10-15 years, we used “free maps” only as a last-resort way to
find a tourism information office or shop that sells real maps. It also used to
be funny and, in a way, interesting, to navigate “map-flavored yellow pages”.
We knew we are looking at an ad brochure and acted accordingly.

These days map-flavored Yellow Pages are embedded into every smartphone, which
we use daily to navigate. I find it quite sad, because constantly projecting
the world through such “maps” results in a very peculiar world understanding.
For those who haven’t tried, it is an interesting exercise to use Yellow Pages
to find playgrounds (when traveling with kids) or water fountains during hot
days.

Even in this era, not all is lost! Technology of real maps is moving and
improving. I will remind you what a real map looks like and show how usable it
is today. During the talk a licensed cartographer will give practical
day-to-day tips for navigation and exploration. In the second half of the talk
we will switch out our consumer hat to a creator hat and behold, create! No
background in cartography required, only a smartphone.

* [Slides](/talks/2024-sycl-maps-and-yellow-pages.pdf).
* Video: [webm](/talks/2024-sycl-maps-and-yellow-pages.webm), [mkv](/talks/2024-sycl-maps-and-yellow-pages.mkv), [youtube](https://www.youtube.com/watch?v=I7fFBJHmCT0)

<hr/>

2022-04-10 Zig Milan Party
--------------------------

**How Zig is Used at Uber**

TLDR from the [blog post]({{<ref "log/2022/how-uber-uses-zig" >}}):

* Uber uses Zig to compile its C/C++ code. Now only in the [Go
  Monorepo][go-monorepo] via [bazel-zig-cc][bazel-zig-cc], with plans to
  possibly expand use of `zig cc` to other languages that need a C/C++
  toolchain.
* Main selling points of C/C++ toolchain on top of zig-cc over the
  alternatives: configurable versions of glibc and macOS cross-compilation.
* Uber does not have any plans to use zig-the-language yet.
* Uber signed a support agreement with Zig Software Foundation (ZSF) to
  prioritize bug fixes. The contract value is disclosed in the ZSF financial
  reports.
* Thanks to my team, the Go Monorepo team, the Go Platform team, my director,
  finance, legal, and of course Zig Software Foundation for making this
  relationship happen. The relationship has been fruitful so far.


Presentation:

* [Blog post]({{<ref "log/2022/how-uber-uses-zig" >}}).
* [Slides](/talks/2022-zig-milan-party_How-zig-is-used-at-Uber.pdf).
* Video: [webm](/talks/2022-zig-milan-party_How-zig-is-used-at-Uber.webm), [mkv](/talks/2022-zig-milan-party_How-zig-is-used-at-Uber.mkv), [youtube](https://www.youtube.com/watch?v=SCj2J3HcEfc).

<hr/>

2016-11-18 Build Stuff Vilnius
------------------------------

**Understanding and building your own Docker**

Docker started small and got big in really short time. Believe it or not, you
can learn to build your version of it too, within the duration of a conference
talk!

In the talk, we will assemble and run a Docker-like container with only
standard command-line tools found in modern Linux distributions.

First half of the presentation will cover the facilities Linux provides for
Docker to build upon: cgroups, pid and network namespaces, overlay file
systems. During the second half we will put theory to practice in a terminal
session. At the end of the talk we will not only be armed with knowledge how to
build an isolated container, but also have an actual container running.

After the talk, you will have a good insight how Docker works, and understand
how you could use its building blocks to build something that perfectly matches
your environment.

You’ll get most out of this session if you are comfortable in Linux terminal,
for instance, configuring networking from command-line. Knowledge about Pid
namespaces, cgroups or overlay filesystems is not required. You will learn it
all that during the talk.

* [Slides](/talks/2016-buildstuff-understanding-building-your-own-docker.pdf).
* Video: [mkv](/talks/2016-buildstuff-understanding-building-your-own-docker.mkv), [youtube](https://www.youtube.com/watch?v=vYZKxVkUMvQ).
