Why some DVLA digital services don't work at night

Something is missing here, why do batch jobs take 13 hours? If this thing was started on an old mainframe why isn't the downtime just 5 minutes at 3:39 AM?

Exactly how much data is getting processed?

Edit: Why does rebuilding take a decade or more? This is not a complex system. It doesn't need to solve any novel engineering challenges to operate efficiently. Article does not give much insight into why this particular task couldn't be fixed in 3 months.

It’s funny to me that I would never ask those questions. I’ve specialized in legacy rehab projects (among other things) and there seems to be no upper bound on how bad things can be or how many annoying reasons there are for why we can’t “just fix it.” Those “just” questions—which I ask too—end up being hopelessly naive. The answers will crush your soul if you let them, so you can’t let them, and you should always assume things are worse than you think.

TFA is spot on - the way to make progress is to cut problems up and deliver value. The unfortunate consequence is that badness gets more and more concentrated into the systems that nobody can touch, sort of like the evolution of a star into an eventual black hole.

I made a lot of money moving mid size enterprises from legacy ERP systems to custom in house ones.

The DVLA dataset and the computations that are run on it can be studied and replicated in 3 months by a competent team. From there it can be improved.

There is no way that this system requires 13 hours of downtime. If it required two hours - even if the code was generated through automation it can be reverse engineered and optimized.

It is absolute rubbish that this thing is still unavailable outside of 8am-7pm.

I maintain my position that it could be replaced in 3 months.

I got my start in this business when I was in university and they told us our online learning software was going offline for 3 days for an upgrade. Those are the gatekeepers and low achievers we fight against. Think bigger.