I cannot speak for Jane Street, in particular, but I have spent many years working at a very similar firm, and Investment is not Technology.

There are engineers working in Investment, yes, but the risk profiles, the payout profiles and the focus of their work is very different. Investment deals with getting and analysing data, understanding the market and their algos, coming up with trading ideas, handling their PB relationships, doing the actual trading (e.g. portfolio optim, factor hedging, worrying about financing and borrow costs) etc. Technology deals with all things infra and (in most places) ingesting data and making it easily available internally.

In particular, I would be surprised if the interns in this article were on the Investment side - a fund would rarley publish anything remotely resembling research. In fact:

"Yulan ended up working with both the trading desk that was running this process, as well as the research group, which pointed her at some cleaner cost functions to optimize, as well as encouraging her to try out simulated annealing in addition to the greedy algorithm she started with."

The "research group" and the "trading desk" are Investment.

It's too hard to fully explain how wrong this is, so just leaving the comment in case someone else reads it and thinks it might be right.

The investors are engineers. Full stop. They write code. The code makes trades. Everything else is noise to support the engineers writing code to make trades.

You can tell someone worked on the old wallstreet when they jump to explain that engineers are not a part of the core finance business. I've seen this trope a million times, and it used to be true. In 2020, the hedge funds making the most money are the ones treating their technology people like they treat their investment people. They interact, receive similar (though not 2M+) pay, and the programmer often has a part in analyzing the data and building the libraries to push the research forwards.

You're basing your assumptions on very little information. In particular, my position was with a buy-side fund set up in the last 5-10 years. It was definitely not "old wallstreet".

I worked at a well known hft prop trading firm, and then at an asset manager. The asset manager was staffed by mostly ex two sigma software engineers, a few from tower research. You basically cant even get an interview there unless you already worked with someone working there. A regular engineer there, a few years of experience made around 650k. I know the industry extremely well, and I know your type. I've watched so many buy side firms fall to the wayside because "good tech doesnt help investing, I will hire the humanities degree from princeton instead". Meanwhile, run through the top returning firms in the last decade, they all also happen to be the firms that pay their engineers the most.

When I worked on Wall Street even the IT guys and the doorman had their personal accounts invested at the firm which was a significant perk given that the firm was closed to new customers.