Blog on Jon Seager

Canonical is funding a 3-year PhD at the University of Bristol to investigate whether large, mature C codebases can be translated into safe, correct and maintainable Rust.

Development of the upki project, which aims to bring browser-grade cryptography primitives to low-level Linux system utilities, continues at pace.

I recently attended Ubuntu Summit 26.04, a twice-yearly showcase for innovative and ambitious work across Ubuntu, open source, and the wider technology ecosystem.

AI tools are becoming ubiquitous.

Ubuntu is transitioning to the Rust-based ntpd-rs as its default time synchronization utility, replacing chrony, linuxptp, and gpsd to deliver a unified, memory-safe solution for NTP, NTS, and PTP.

I built a self-hosted coffee logging platform with Rust, Axum, SQLite and Datastar.

This post provides an update on the Canonical-supported upki project, which brings browser-grade Public Key Infrastructure to Linux through the efficient CRLite data format, with the core revocation engine now functional and available to test.

AI-assisted tooling is becoming more and more common in the workflows of engineers at all experience levels.

Announcing work on upki, a universal tool for Linux and other Unix-like operating systems for handling X.509 certificate revocation lists in system utilities.

I recently had the privilege of attending the Ubuntu Summit 25.10 - an event hosted by Canonical to celebrate the release of Ubuntu 25.10, and provide a platform for open source projects from around the globe to showcase their work.

In February this year, I posted a manifesto to to modernise the design, build and release of Ubuntu.

Immutable Linux distributions are gaining popularity due to their resilience and security, with mainstream operating systems adopting similar principles.

Packaging software is notoriously tricky.

Introducing Canonical’s new Debcrafters team, dedicated to maintaining the health of the Ubuntu Archive, but also to fostering collaboration among Linux distributions, including paid time to contribute elsewhere in the open source ecosystem.

This year, I moved from NixOS to Ubuntu.

We’re building a new, automated release system for Ubuntu to make releases more reliable, observable, and testable.

A follow up to “Carefully But Purposefully Oxidising Ubuntu” in which I describe the plan to migrate to sudo-rs by default in Ubuntu 25.10.

An article outlining my plan to revamp Ubuntu’s ‘project documentation’, illuminating the path for new contributors and enabling better distributed decision making.

This post explores modern equivalents of foundational system utilities such as coreutils and sudo, introduces an experimental utility for testing them, and maps out a path to their widespread adoption in Ubuntu.

Managing your time can be hard, particularly when occupying leadership positions.

In the last week of January 2025, I was appointed VP Engineering for Ubuntu at Canonical, meaning I’ll oversee the Ubuntu Foundations, Server and Desktop teams going forward.

Multipass’ GUI application recently got a huge rework.

A post outlining my journey into Rust, and how I reimplemented the server that powers this very website in Rust, then benchmarked both the old and new implementation with K6, investigated a performance issue with Parca and then automated the whole lot usi…

A short blog post explaining how I replaced a proprietary wireless temperature monitor for my hot tub, with a simple ESP32 based micro-controller and a cheap bluetooth pool thermometer, all linked up with Home Assistant.

Part 2 of a micro-series of blog posts that outlines my journey toward authoring a Home Assistant Core integration for the Roth Touchline SL heating system.

Part 1 of a micro-series of blog posts that outlines my journey toward authoring a Home Assistant Core integration for the Roth Touchline SL heating system.

A deep dive into my home grown cocktail recipe app which speaks Tailscale natively using tsnet, and serves up delicious drinks direct to your tailnet.

An extended “uses” post that outlines the hardware I’m currently using, the software and tools that I use to get things done, and how I configure things.

An overview of Multipass and LXD, and how I use them for creating, managing and enjoying virtual machines on my workstations and servers.

A walkthrough of a simple release & CI tracking system I built for keeping track of the various teams I manage at Canonical using a small Go application, Hugo and Github Actions

An explanation of how to enable secure boot on NixOS, using a community project named ‘Lanzaboote’, and further how to automatically unlock a LUKS-encrypted disk using a TPM with systemd-cryptenroll.

The community-led organisation Snapcrafters maintains hundreds of Snap packages, with hundreds of thousands of users.

The homepage-dashboard NixOS service previously enabled the deployment of the wonderful homepage dashboard, but its configuration was not handled natively in Nix by the module.

A follow on from my last post, outlining the process of upstreaming Scrutiny to nixpkgs to make it easier to consume, and have it included in future NixOS releases.

A detailed walkthrough how I packaged Scrutiny, a S.M.A.R.T disk monitoring tool, for NixOS.

A write up of how I boot KVM accelerated NixOS VMs on Github Actions runners in order to run end-to-end tests for my packages.

Documenting how I render, serve, build and deploy my personal website and blog using a combination of Go, Hugo, Nix and Fly.io.

(Repost) A write-up of my adventures with Parca, and building a Snap package, as well as a set of charms for driving Parca and profiling applications run with Juju on machines and Kubernetes.

(Repost) Building a zero-trust, serverless authentication system for SSH on Microsoft Azure, complete with custom ssh-agent and serverless certificate authority.