Weeknotes for the week finishing Friday, 12th June 2026.

Two weeks’ worth of weeknotes this week.

Meetings aside, I’ve spent much of my time trying to understand why DuckDB ran out of memory during a long-running process. The problem started when I was taking annual leave, so my first …

Weeknotes for the week finishing Friday, 29th May 2026.

No weeknotes for last week or the week before, because I was taking annual leave.

This week, I:

• deployed OpenPathology. It’s a Streamlit app running on App Platform. Whilst deploying it wasn’t exactly easy, it was easier (and cheaper …

Weeknotes for the week finishing Friday, 8th May 2026.

Two weeks’ worth of weeknotes this week.

Last week I was in Birmingham (“You feel as if you’ve been projected into the 21st Century”), meeting with my Bennett Institute colleagues. There were sessions on LLMs, OpenSAFELY, and OpenPrescribing, as well …

Weeknotes for the week finishing Friday, 24th April 2026.

This week, I:

• side-stepped a problematic dependency update in OPv1.
• thought about overhang.
• asked “What’s the point of code review?”

Overhang

Last week was the final week of our current cycle, during which we added dm+d forms/routes and …

Weeknotes for the week finishing Friday, 17th April 2026.

This week, I:

• continued the crash course in SSL certificates that I started last week.
• finally (finally!) felt as though I understood the OpenPrescribing v2 codebase.
• read an editorial in the BMJ about protecting health data by Jess Morley, a former …

Weeknotes for the week finishing Friday, 10th April 2026.

This week, I:

• Fixed a bug in production. The SSL certificate didn’t automatically renew. It expired, leaving a Cloudflare “Invalid SSL certificate” message in place of OpenPrescribing v2 for about 40 minutes early this morning.
• Started work on a new …

Weeknotes for the week finishing Friday, 3rd April 2026.

Two weeks’ worth of weeknotes this week.

Last week I was in Oxford, celebrating the award of the Queen Elizabeth Prize for Higher and Further Education. This coincided with my five year anniversary at the Bennett Institute for Applied Data Science …

Weeknotes for the week finishing Friday, 20th March 2026.

This week was emotionally draining. It ended with a moment of clarity that made me rethink the last three months.

For now, I’m going to link to three posts that Ben B.C. recommended:

• “Creating momentum when an employee is …

Weeknotes for the week finishing Friday, 13th March 2026.

This week, I:

• continued to write KPIs;
• added some extra meetings to the calendar: several short daily standups and a longer weekly team meeting;
• gave a show-and-tell about our second three-week cycle on OpenPrescribing v2;
• read a paper about how to …

Weeknotes for the week finishing Friday, 6th March 2026.

This week, I:

• was reminded (again) that people issues are harder than technical issues;
• started writing some KPIs;
• started writing another pitch;
• read a blog post about LLMs by the creator of htmx. (Thank you for the link, Simon.)

Pitches

In …

Weeknotes for the week finishing Friday, 27th February 2026.

This week felt like a tipping point: I started using an LLM to write code.

Before this week, I’d used ChatGPT’s web app to ask “How do I?” questions.

• How do I count the number of NaN values in …

Weeknotes for the week finishing Friday, 20th February 2026.

We started our second three-week cycle on OpenPrescribing v2 this week. We’re focusing on “more effective visualisations”. However, I spent much of this week fixing, or trying to fix, OpenPrescribing v1. Its VM frequently runs out of CPU and memory …

Weeknotes for the week finishing Friday, 13th February 2026.

As I mentioned last week, we’re working on OpenPrescribing v2. We finished a cycle last Friday and will start a cycle next Monday. This week was a deck-scrubbing week; time between cycles to tidy up.

We’ve certainly mixed and …

Weeknotes for the week finishing Friday, 6th February 2026.

This week, I:

• thought about when a user is a user;
• started writing a pitch;
• thought about what happens when “there’s not enough space on the dance floor”;
• learned about servant leadership;
• was reminded (again) that people issues are harder …

Weeknotes for the week finishing Friday, 30th January 2026.

This week, I:

• realised that I’d started, and not finished, half a dozen books on tech leadership/management;
• read a lovely blog post from Will Larson about including engineers in leadership meetings;
• realised that the Eisenhower Matrix works well for …

Weeknotes for the week finishing Friday, 23rd January 2026.

My weeknotes for this week are shorter than usual. I try to start writing them on Tuesday or Wednesday, but it’s Friday afternoon and I’m just starting.

This week, I:

• was an incident coordinator;
• learned even more about BNF …

Weeknotes for the week finishing Friday, 16th January 2026.

This week, I:

• went to Oxford for the OpenPrescribing kick-off meeting;
• wrote two ADRs (Architectural Decision Records);
• learned more about DuckDB;
• learned more about BNF codes;
• wrote issues;
• caught a cold.

ADRs

I want to write a little about ADRs, because …

Weeknotes for the week finishing Friday, 9th January 2026.

This week, I was occupied by setting up the new team. We’re working on OpenPrescribing, but as there’s already a group of people who are associated with OpenPrescribing,¹ and as that group of people refer to themselves as …

Weeknotes for the week finishing Friday, 2nd January 2026.

After another hiatus, weeknotes are back. A lot has happened in the last six months. Nevertheless, these are weeknotes. What happened this week?

I’ve been reading about prescribing data, BNF codes, and dm+d codes in preparation for starting work …

Weeknotes for the week finishing Friday, 20th June 2025.

I’ve been reading about continuous integration (CI) and continuous delivery (CD), and trying to imagine software development without pull requests (PRs). Although Ben B.C. has talked about this before, my prompt was returning to a PR with unresolved comments …

Weeknotes for the week finishing Friday, 13th June 2025.

As last week, additional paternity leave!

This week I learnt about git rebase --committer-date-is-author-date. Normally after a rebase, the author date is that of the original commit but the commit date is that of the new commit. With this option, the …

Weeknotes for the week finishing Friday, 6th June 2025.

Paternity leave! More specifically, additional paternity leave!

The University of Oxford Additional Paternity/Partner Leave scheme means I have 10 additional weeks of paternity leave. Needless to say, the scheme is amazing.

Last week I started thinking about pair programming as …

You’re a junior academic at a British university. You know it’s important to publish your research in high-impact journals. You’re already the first author on several papers. But you’re worried: you need more. And the journals aren’t high-impact enough.

Someone from the university’s Department …

Weeknotes for the week finishing Friday, 30th May 2025.

I updated my script for creating weeknotes. It now creates an article for a given date, rather than for today’s date, which means I’m less likely to run it on Friday and struggle to remember what I did that …

I became a tech lead in December 2024. My team is small: just Alice, a junior developer, and me. We were asked to work alongside researchers and health informaticians on the OpenPathology project with the aim of designing, implementing, and evaluating dashboards. Here, I’d like to reflect on my …

Weeknotes for the week finishing Friday, 23rd May 2025.

Katie showed me a code snippet within which I noticed the following idiom:

del a_list[:]

I was sure that [:] copied the list, but I wasn’t sure what del did to it. Deleted a copy of the list? Deleted the contents …

Weeknotes for the week finishing Friday, 16th May 2025.

Annual leave!

For several reasons I found myself going to bed and waking up early. I started reading about Rust (it’s a programming language, dad) and working through the Getting Started section of The Book. I was impressed by the …

Weeknotes for the week finishing Friday, 9th May 2025.

After a hiatus, weeknotes are (hopefully) back. In the last six months, I’ve become a dad, taken a month off, and become a tech lead. Nevertheless, these are weeknotes. What happened this week?

Several things happened this week, but I …

Weeknotes for the week finishing Friday, 8th November 2024.

I wrote these on Monday, 11th November. I struggled to remember the previous week!

The REX (Researcher EXperience) team started a new initiative: “Onboarding OpenCodelists”. Lucy and Mary asked us to split into two squads. One squad will focus on maintaining …

Weeknotes for the week finishing Friday, 1st November 2024.

Annual leave!

We went to on holiday. Some walking, some paddleboarding, some running.

Weeknotes for the week finishing Friday, 18th October 2024.

I’m back after a two-week hiatus.

Katie and I have reduced the frequency of our meetings, which I think has helped each of us focus on our other tasks. We’re now meeting on Monday, Wednesday, and Friday mornings for …

Weeknotes for the week finishing Friday, 27th September 2024.

This was my third full week as Katie’s buddy. We covered:

• When QuerySets are evaluated
• The nature of the SQL statements generated by Django’s ORM
• List comprehensions (listcomps)
• Breakpoints, the Python debugger, and pdb++
• Django Debug Toolbar
• Django …

Weeknotes for the week finishing Friday, 20th September 2024.

This was my second full week as Katie’s buddy. We covered:

• the Django shell (manage.py shell)
• the database shell (manage.py dbshell)
• displaying two shells in one window with Terminator
• creating and saving models with managers and instances
• environment …

Weeknotes for the week finishing Friday, 13th September 2024.

This was my first full week as Katie’s buddy. We covered:

• setting up a GPG key
• the differences between a GPG key and an SSH key
• signing commits
• the pros and cons of HTTP and SSH for communicating with a …

I gave a talk today at the NHS-R conference. It was called Less neat, less tidy, and more unpredictable: Improving your code with property-based tests.

Abstract

As conscientious data scientists, we know that it’s good practice to write unit tests to check that our code is working correctly …

I gave a talk today at the NHS-R conference. It was called Code Reuse in a Trusted Research Environment: Reusable Actions in OpenSAFELY.

Abstract

OpenSAFELY is a secure, transparent, open-source software platform for analysis of electronic health records data. It can be deployed to create a Trusted Research Environment …

I gave a short talk today called A Constellation of Data Visualization Tools: Vega, Vega-Lite, and Altair.

The first part of the talk was a brief history of data visualization tools. I described how the ideas in Leland Wilkinson’s The Grammar of Graphics are related to those in ggplot2 …