What might an "urgent new feature" consist of? Well...
The Swiss Franc is no longer pegged to the Euro, so our trading software needs to track a separate currency, and also we need to stop trading EUR/CHF forex pairs as if they were still pegged; we lost $2 million before I turned the system off this morning. The new version of IOS doesn't support the old SNMP MIB, and our customer has already installed it. The vid.me domain has been bought by a porn spammer and now we have hardcore porn ads on all our news articles.
YouTube revved their AJAX and our video metadata scraper stopped working. We're being hit by an 0.1Mbps DoS because this one page takes a whole CPU second to render. The new satellite downlink site came online six months earlier than expected, so our comms software needs that multisite feature next week instead of in six months, or we're paying a shitload of rent for nothing. Modi demonetized large bills last night, so we need to stop accepting them at our ATMs. Apple told us yesterday they won't approve our update to the iOS app unless we add in-application purchases (and disable every other payment method).
We signed a contract to provide security for a new film, but they're filming onsite at an Air Force Base, so we need a field in the database for which security guards are cleared to go on the base, and filming starts on Monday. Turkey just ran all their ISPs through CGNAT, which means we need to fix our NAT traversal strategy so it works through two layers of NAT, or we lose half our Turkish users. Russia is fining us $100,000 a day until we move all the data about Russian users onto our Russian server.
Our popular webcam software just doesn't work with this popular new webcam. We've identified a new signal in the market that we think will give us 0.7ยข per trade, but someone else will probably exploit it within the next two weeks, and then it won't be profitable anymore. It looks like Berkshire Hathaway is going to break US$671088.64 per share this month, and we need to be able to handle that. Apple just announced that in iOS 11 the default video codec is HEVC, so unless we tell our users how to reconfigure the Camera app (and they reshoot their videos) we need to be able to handle HEVC uploads before people upgrade their phones to iOS 11.
NCMEC just gave us the new version of their damn fuzzy hashing algorithm; they'll start giving us hashes in that format next month, and if we don't support it by then, we're kiddy porn purveyors. Oh, Argentina canceled daylight savings time with 11 days of warning, so all those calendar entries our users scheduled two weeks from now, they now have the wrong UTC time and need to be fixed, plus we need to roll a timezone update. We finally signed the deal with Nicki Minaj to make her a character in the game we were about to ship, but we can't slip the ship date past Black Friday or our sales will take a huge hit.
(Names and details have been changed to protect the guilty. Some events haven't happened yet.)
I have no idea what project you work on, but that sounds like 30 different teams each experiencing:
1. Rare actual urgent issues
2. Shit leadership adding last minute requirements (that no scrum or waterfall or agile whatever would help with)
3. A bunch of config changes (I worked on payments systems in the past. We had some contractors who would basically mess with config files all day as countries changed laws, etc).
4. Stuff that only quant firms care about
Regardless, you didn't address the second part of my comment: What does the fact that we'd have to stop other work have to do with anything? That'd be the case for any workflow structure.
As someone who has spent most of their 7 year career at big companies that follow "plan build ship" cycles, I don't understand this post.
What abrupt new feature with urgent deadlines? Why can't this hypothetical feature wait?
Sure, for Coronavirus teams spun up and other work stopped, but that's a pretty big outlier. Most features are planned a quarter or so ahead.
> Do you just keep a copy of your old work, and start working on this new stuff
Sure why not? I don't understand how any "abrupt new feature with urgent deadlines" wouldn't require stopping what you're currently doing.
Besides, it's not like I sit on massive code changes for weeks. I submit code incrementally.