Comment by mootothemax
1 day ago
> Think bigger.
One of the easier parts of this involves addressing, which in the UK is notoriously easy, reliable, and easy to process - especially the best-in-class Ordnance Survey stuff like AddressBase Premium, right?
A quick trawl of Github will shed some light on it - especially how much of a pain it is to get ABP into a usable state - and this is data that's core and integral to the service, the "are you a real user, a typo, a fraudster, a data supply issue, or getting things wrong in good or bad faith?" kind of business logic.
And it's doubly hard, because the government requires people to update their license when they change address - which often enough involves a new-build property, where the address (let alone UPRN - sometimes even the USRN!) is completely new to you.
Thinking bigger: imagine sitting at your desk during the first couple of weeks on the job, database validation checks running merrily in the background while you're staring at a screen. There's a mild frown forming on your face. You'd been scrolling over a list of rejected records in front of you, largely looking good - _how did they miss THAT fraud _ you'd briefly chuckled to yourself - but _this_ one...
It's a valid business entity, trading from the valid address, and you've hand-checked both _and_ got a junior who lives nearby to send you a photo of it, and, well, the wit running the business has decided to trade under the name _FUCKOFFEE_, and... that's... just going to have to be someone else's problem, you shrug.
(to be clear: the hard part of the DVLA project is _not_ implementing the coding, database, and systems design work)
You've sort of identified how to do it: break it up into problems.
Addresses are hard? Use https://postcodes.io or make your own - that's a project in its own right.
Separately out trading name from registered names needs to be an API from Companies House, or an internal service that API-ifies Companies House data.
Fraud detection? That needs to sit somewhere - let's break out all the fraud detection into a separate system that can talk to the other systems, and have it running continuously over the data. It'll need people to update fraud queries and also to make sure the other systems' data stays integrated with it.
Finally you need something on top that orchestrates the services and exposes them via a gov.uk website, and copes with things like "I don't have my address yet; can I use What3Words instead?" and another one with a UI and lots of RBAC and approvals for DVLA users to do lookups and internal admin.
Heh, you’ve fallen into the exact trap I was trying to expose, which is why I chose addresses as an illustration point :)
The first step with anything address-y is to try and nail down exactly what an address is in the project context. Quick example - property shells, a building at 1-2 Street Name that contains a bunch of flats, but doesn’t itself have residents or its own postal delivery point. They’re mega useful for an address autocomplete (sadly, the vast majority of geocoders are trash for the uk’s addresses), are they sth people should be able to use (without a flat number etc.) for their driving license? Probably not. Commercial venues? Maybe, what about pubs? Ok, so dual-use maybe, but man this stuff gets painful in a hurry.
Next up - historic addresses and how’re you going to link ‘em all together. It’s nasty, edge-case-strewn work - and for the most part, unavoidably so. It’s why people get their backs up when someone dismisses it out of turn, cos if they have worked with it in the past, they’d qualify anything they wrote with: * presuming a well-formed address source + pipeline.
Edit: for what it’s worth, companies house only lists corporate entities and partnerships as defined in whatever act of parliament. Self employed etc can call themselves whatever - and do! - and the only record of it can be as vague as a nondescript line from the VOA.
I like this trap. Why would you need historic addresses for this service? In my mind the main reason for the DVLA knowing your address at all is so they know where to post a fine and a new driving licence/car documentation to. Why do they need historic addresses in their core system?
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