My work in detail#

IRRD version 4#

IRRD is a routing registry daemon: software that lets network operators publish information about their networks so that others can use it to configure routing automatically. Most network operators on the internet depend on it directly or indirectly.

When I started this project, the existing codebase was essentially unmaintained and had accumulated decades of technical debt. The challenge wasn’t just rewriting it, but also remaining compatible with the existing ecosystem of operators who had built their configurations around its quirks.

I rewrote IRRD from scratch in Python, with extensibility, reliability, and backwards compatibility as core constraints rather than afterthoughts. This included a thorough test suite and automated comparison against previous versions to catch any behavioural differences. NTT Communications was the first major production deployment in 2019. Since then it has been adopted by ARIN, LACNIC, RADB, LEVEL3, TC, IDNIC, and others.

I continue to develop IRRD in close collaboration with IRR operators, network operators, and others in the ecosystem. I’ve extended it with RPKI validation, new interfaces, APIs, security features, and many others.

NRTMv4#

IRR registries typically mirror data from each other, and this needs to be reliable. The existing protocol for this (NRTMv3) was showing its age: it had poor security and many hard to detect failure modes.

I co-authored NRTMv4 to fix this, and implemented it in IRRD. The draft (draft-ietf-grow-nrtm-v4) is progressing through the IETF GROW working group.

internet.nl#

Internet.nl is a standards compliance testing tool run by a collaboration of the Dutch internet community and government. Since 2022, I work as lead developer on a freelance basis.

This project interesting and demanding due to its breadth. The tool covers IPv6, DNS, RPKI, TLS, DANE, SPF, DKIM, DMARC, and more, running around 9 million tests a year. That means getting the technical implementation right, but I also contribute to deciding what “correct” actually means across all of these standards, and making those judgments in a way that holds up to scrutiny. The Dutch national government uses internet.nl for periodic compliance reporting, and it is widely used in the commercial sector too.

My responsibilities cover day-to-day development, long-term sustainability, testing criteria, deployment, and product direction. I am part of the decisions on what to test and how, which means being familiar with many standards simultaneously and being able to research and take positions on them.

IRRexplorer#

IRRexplorer helps network operators find and fix problems in their IRR configuration. Misconfigurations of this kind can quietly cause routing issues that are annoying to diagnose.

The previous version had accumulated its own set of problems: a difficult codebase, incomplete analysis, and a UX that made it harder than it needed to be to get useful answers. I built a completely new version from scratch for Stichting NLNOG under a grant from the RIPE NCC Community Projects Fund, with deeper analysis and a cleaner interface. It’s now widely used across the operator community.

MANRS analysis tools#

MANRS is an initiative to encourage responsible routing practices among network operators. Measuring actual compliance, as opposed to self-reported compliance, requires looking at real routing data. I built tooling to do that, analysing route server and RPKI data to give the initiative a concrete picture of where adoption stood and where the gaps were.

Write the Docs#

In 2018, I joined the Write the Docs core operations team after several years of volunteering. Write the Docs is a global community for documentarians with over 5000 members and multiple conferences every year, with nearly 1000 attendees in total.

I work on conference organising, website development and automation, support, and general community management, and currently serve as conference chair of Write the Docs Berlin.

IETF datatracker & meeting scheduler#

The IETF datatracker is the central tool for tracking standards work, including document reviews. It’s a Python/Django codebase, and I designed and implemented architectural improvements to the review tooling alongside fixing a range of issues.

I also built an automatic scheduler for IETF meetings. Scheduling over 100 sessions with overlapping constraints, time zone considerations, and room requirements is hard to do well by hand. The automatic scheduler substantially reduces the manual effort involved.

Django web framework#

Django is the most widely-used open source web framework for Python. I was a committer and team member until 2018.

My first major contribution was IPv6 support across the ORM and other parts of the framework. I also designed and developed modular password validation: a system with sensible defaults that’s easy to extend or connect to existing authentication infrastructure. I was vice chair of the Code of Conduct committee and helped organise four major Django conferences.