Comment by abigail95 2 days ago
The code will be spaghettified and hideous. The queries will be nonsense.
That doesn't change the fact that the ultimate goal of the system is to manage drivers licenses.
> In my experience you can't rebuild such a thing "in 3 months".
Me and my team rebuilt the core stack for the central bank of a developing country. In 3 months. The tech started in the 70s just like this. Think bigger.
For some reason those comments always seem to imply that every business doesn't have these problems too.
Every business has these problems. In most cases, the ones who don't change get swept away. The places that do not change are usually ones that can't go out of business. But every place has systems like this, you have to rebuild them, it isn't fun but there is no choice.
A tiny system like the DVLA is complex, hilarious (this is the same place that has had to reduce service provision because some staff just stopped turning up for weeks after Covid, public-sector productivity in the UK is at the same level as 1997, to just get to the same level as the private sector...which isn't growing productivity very fast...you would need to fire ~2m workers, the total workforce in the UK is 30m btw).
I worked for an aircraft parts manufacturer, they closed an entire factory / production site rather than try and upgrade the manufacturing system or move the part production onto the new one they had implemented.
500 people out of work. Tell me again how simple everything is to fix.
> 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?
Yeah, I always raise an eyebrow at attitudes like that too.
I've also reimplemented or gradually replaced several out-of-date systems. Albeit on a smaller scale.
In my experience, when you start picking the programs apart you find 90% of the code is redundant or boilerplate. Much of it isn't even called from anywhere, abandoned code, and can be deleted en masse. A lot of programmers don't clean code up "just in case" and then no-one else deletes it.
They can also often be vastly simplified because programmers back then didn't have the patterns and knowledge to write consisely.
I often find myself simplifying the original code first, which gets rid of 50% of it. Then I can see what the code actually does and rewrite it which gets rid of the other 40%.
On the other hand, many programmers don't have the patience, stubbornness or skill to do this kind of work.
And the ability to get through the major panic you have when you're half way through and wondering if you were mad to even start.
> And the ability to get through the major panic you have when you're half way through and wondering if you were mad to even start.
I feel seen, thank you.
Good for you, it means either your system was sufficiently simple to be fully implemented in 3 months from scratch including all business rules, or you build a new system which left out some amount of rules from the original system without this posing a problem. I don't know much about how central banks work so that might be possible. But not all systems present those characteristics.