Week 910

Week beginning Monday, 22nd June 2026.

I was out for a chunk of the week due to tooth pain, but Chris L & Chris R continued to work on performance-related improvements for the Mavis project for NHS Digital. Chris L identified a small change to a gnarly SQL query used to search for patients which led to a significant improvement in performance.

Chris R shipped a change to use Sidekiq Pro in all environments which was a bit tricky because it means we now require some credentials wherever we need to run bundle install. We’ve chose to use mise with fnox backed by encrypted values in the AWS Parameter Store to avoid every developer having to store the credentials locally.

Chris L attended Brighton Ruby on Thursday. He said there were some interesting and relevant talks on Sidekiq and performance testing. He also got to catch up with lots of familiar faces from the Government Digital Service, FutureLearn, Nesta and the Raspberry Pi Foundation. I was pleased to hear that the venue was air-conditioned this time which must have been a mercy given the record temperatures in the UK.

Chris L has also been busy this week sorting out a bunch of admin for the Scaling Co-operation event that he helped organise a couple of weeks ago.

I spent some time last weekend trying to ship the Stripe Connect changes for Jam I’ve been working on for months on & off. While I did end up merging the changes (behind a feature flag), I’ve slightly lost confidence that the current iteration of the implementation is sensible.

This latest doubt came from looking at the way DoubleAgent’s Stripe integration works - it has built-in support for application fees. While originally we had hoped to use these application fees to account for Jam’s platform fees, our latest implementation doesn’t use them, because it was the only way we could get Stripe Connect not to pass the VAT paid by the customer to the artist.

To be honest I’m a bit baffled why Stripe Connect makes this (seemingly very common) use case so hard. Anyway, hopefully I can chat to the others and work out a way forward.

Until next time!

– James