Application - Core Developer - Jonas Jelten

Community Ubuntu Developer Membership
1

I, Jonas Jelten, am applying for upload rights for Ubuntu core developer rights.

Name Jonas Jelten
Launchpad Page https://launchpad.net/~jj
GitHub Page https://github.com/TheJJ
Matrix @jj → :sft.lol

I am applying because:

  • I’d like to reduce sponsorship burden on my team ✓
  • I’d like to eliminate delays in getting my work sponsored ✓
  • I need the ability to restart failed builds independently to save others’ time ✓
  • I want to help sponsor and mentor other contributors, enabling more community work to land ✓
  • Increasing my direct involvement allows me to better assess and implement improvements for distribution tooling and infrastructure ✓ :smile:

Who I am

Hey! I am Jonas (jj), a software engineer within the Ubuntu Server team.
My primary focus is creating updates and bugfixes for various Ubuntu packages, as well as developing and maintaining project and team infrastructure.
Currently, I am actively improving and extending git-ubuntu, our daily triage tooling (startriage, which may be useful for your team!), and Ubuntu’s debuginfod.

Before joining Ubuntu, I worked at the IT Operations datacenter at the Technical University of Munich (TUM), I studied there before. Among many infrastructure improvements and new services (LXD, BBB, Ceph, …), I created ceph-balancer, an advanced optimization tool designed to increase available storage in Ceph clusters.

Outside of work, I collaborate with friends on projects I find interesting.
Some of these relate closely to Debian/Ubuntu, such as our vision for modernized .deb packaging with debmagic :magic_wand:.
My open game engine for Age of Empires has attracted over 14k stars on GitHub.
I drove the development of StuStaPay, an electronic NFC-based payment system for large-scale events (I co-organize StuStaCulum).
This system runs on the infrastructure of StuStaNet, a non-profit ISP organization where I remain an active contributor.
I’m driven by the infinity of available inventions and improvements in the (free) software world, so we can have more happy places of awesomeness!

My Ubuntu story

My journey began in 2008. After hearing about Ubuntu from a friend, I quickly discovered that the free software world was my true home.
While I experimented with Arch and Gentoo to curiously discover how a Linux distribution works internally and to customize it, I always kept Debian and Ubuntu as the standard for my servers.

During my studies, I worked for the StuStaNet ISP, which runs entirely on Debian.
Later, at the TUM ITO datacenter, nearly all of the thousands of machines powering the university and research infrastructure were running Ubuntu.
To take my free software contributions to the next level, I decided to work for Ubuntu full-time, and I am now proud to be part of the Ubuntu Server engineering team.

Examples of my work / Things I’m proud of

Quick links: Uploads on UDD, Launchpad Uploads

Below is a selection of my contributions since May 2025 until January 2026.

Ubuntu contributions

main inclusion requests

feature freeze exceptions

fixes and SRUs

merges and syncs

upstream contributions

Areas of work

Currently my involvement is:

  • Packages
    • openldap
    • multipath-tools
    • nginx
    • ipxe
    • sssd
    • dovecot
    • postfix
    • unbound
    • bacula
    • lftp
    • strace
    • and drive-by contributions and backports in various other packages
  • Infrastructure & tooling
    • git-ubuntu
    • startriage
    • ubuntu-debuginfod
    • debmagic

I work within the Ubuntu Server team, collaborating closely with my colleagues to ensure precise and reliable delivery.

Things I could do better

  • In reviews or design decisions details are important, but I can improve on focusing more on more the overall effects and bigger picture.
  • I should investigate more infrastructure bugs, and if possible propose fixes.
  • I’d like to focus more on meaningful contributions, to better priorize among the infinity of todos.

Plans for the future

General

I intend to encourage and unblock more contributions to Ubuntu by sponsoring community uploads and decreasing the workload on my team members by handling my uploads independently.

My long-term goal is to modernize distribution tooling.
I want to improve components in the current architecture and resolve pain points to enable better working with Ubuntu and Debian, there’s lots of opportunities. I’m working with Launchpad to get a better integration of git through git-ubuntu.

When I become a Core Dev, this allows me to drive improvements in the distro architecture and infrastructure so that everyone can benefit from a stronger foundation.

What I like least in Ubuntu

  • The packaging tooling and infrastructure could benefit a lot from vast improvements.
    For example the autopkgtests and proposed-migration, tracking package file names or debugging symbols should be integrated and made available in real-time in Launchpad.
    The code review UI could be modernized and more integrated and tailored towards Ubuntu development.
    Overall, the number of tools duct-taped onto the Launchpad API is really worrying.
  • The flow of testing package uploads by creating a PPA, creating a source pkg, uploading, running (and making sure to re-trigger) autopkgtest, waiting for results, creating merge proposals, approving should be more automated - I’m working with Launchpad to get improvements here :slight_smile:
  • Debian integration could also be better, like full-automatic update merges (a preview version of this I’ve created in git ubuntu deltarebase, salsa/dgit and git-ubuntu history sharing.
  • A lot of the packaging internals is crafted with rather legacy technologies (Perl and Bash codebases) where seemingly few people dare to touch it, and if, tools remain isolated and quite unmaintained.
    Thus, many tools have been stacked metre-high on top to improve weakenesses in the tool below, but that whole stack isn’t integrated well and each layer missing different features - I wish collaboration and integration of such tools would be increased.
  • I’d love to see more git-based packaging in general, since mixing (or even loosing) rich history due to a lacking upload standard is annoying. I think when the git tooling is good enough, we should completely switch away from tar-based uploads and use git exclusively.
    There’s some remaining problems and usability issues until we’re there, but we should work towards improving.

Endorsements and Comments

If you’ve worked with me or can judge my contributions and their quality, I’d be glad about an endorsement reply to this post :smile:

Here’s a template for your comments:

Endorsement comment inspiration:
- Sponsoring feedback
  Please fill us in on your shared experience.
  - What did you sponsor? A list of sponsored packages can generated [via UDD here](https://udd.debian.org/cgi-bin/ubuntu-sponsorships.cgi)
  - How would you judge the quality and describe the improvements?
  - Do you trust the applicant?
- Specific experiences of working together
  - good examples of your work together, also cases that could have handled better.
- Areas of improvement and next steps
  - What is the journey you see ahead of the applicant, the next steps they should take, the next things they likely have to learn and the next mountains to climb?
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