At nine o'clock, the salon has an appointment available next Tuesday. At nine-oh-one, someone holds it while deciding. At nine-oh-six, that hold expires. Nothing about next Tuesday's opening hours changed, but the answer to “can I book this?” changed twice in…
The nail salon has two manicure seats, and one is empty. Can it take a gel appointment at ten? Perhaps. Someone qualified to provide that service must be working, free for the whole treatment, and allowed to serve this client. An empty seat answers only one of…
You have a collection of things and somewhere to put them. Parcels into boxes. Images into a sprite sheet. Jobs onto machines. Meetings into a calendar. The awkward bit is that “there's enough space” doesn't necessarily mean everything will fit. Over the years…
You search for “deploy an application in a container”. The article you need is called “Getting Started with Docker”. A useful search system should connect those ideas, even when the words don't match exactly. NOTE: Updated 5 November 2026. Rebuilt for .NET 10…
What centuries of payments, promises and disputes can teach developers building systems in the AI age. Traditional banking didn't evolve on the assumption that humans were trustworthy. Much of its machinery exists because they aren't. People lie, forget,…
Behavioural inference, controlled decoys, and some rather sneaky 404s. Someone requests a PHP file from your site. It doesn't exist. You return a 404. A little later, someone else requests the same file. Different address, different user agent. Same small…
Updated - 27 October 2026. Original was published Nov 2025 - Corrected bundle options and added current EF Core 9/10 guidance, Aspire integration and clearly marked EF Core 11 preview features. See the errata at the end for corrections to the original version.…
COMING SOON - Working on the nuget package, stay tuned! In Part 4, the recommendation became an intervention. We characterised a proposed change, applied it under an experiment and learned from the observed response. An email could be a candidate in the same…
The “mind control” in the title is a joke about a familiar ambition: put the right thing in front of someone at the right moment and change what they do next. Most of us have ignored enough perfectly timed marketing emails to know how unreliable that ambition…
In Part 2, we turned an entity's characterisation into recommendations. We could watch a session change, find eligible products, and explain which representations contributed to the ranking. Now we want to use that history to answer a more useful business…