Val on Software Engineering and Collaboration at Jane Street

A London developer explains how colleagues teach new hires, review production code, and work across teams.

VaValIntervenant · Jane Street
Chaîne
Jane Street
Publié
10 mai 2023
Vidéo
3:48
Lecture
2 min
Original
anglais
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RÉSUMÉ

En 30 secondes

Val, a software developer in Jane Street’s London office, describes her path into the firm and the knowledge developers learn on the job. She explains internships as a two-way assessment, the shared responsibility of code review, and how social connections help engineers collaborate across teams.

  1. 1Fundamentals and learning on the jobVal found her computer science degree useful but does not consider it essential. Developers need some knowledge of data structures and algorithms, and colleagues have helped her learn what she did not study.
  2. 2No finance background requiredVal arrived knowing neither finance nor OCaml. She says the firm teaches people the knowledge they need, including basic financial concepts.
  3. 3Internships work both waysInterns are placed in situations that show them what working at Jane Street is like, so they can decide whether they want the full-time job.
  4. 4Shared responsibility in code reviewMost code is written by one person and reviewed by another. The reviewer signs off through a process called seconding, sharing responsibility with the author.
  5. 5Cross-team connectionsAs a desktop developer, Val works closely with traders but also uses libraries and applications from other teams. Engineers can approach library authors for help or reviews, and social connections make collaboration easier.

À retenir

  1. Computer science fundamentals are useful, while colleagues can teach skills that a new developer has not yet learned.
  2. Val joined without knowledge of finance or OCaml and learned what she needed at the firm.
  3. Internships let candidates assess the full-time job as well as letting the firm evaluate candidates.
  4. Code authors and reviewers share responsibility for production code through a review and sign-off process.
  5. Informal relationships across engineering teams make it easier to ask questions and help one another.
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Transcription seule
01

Background and learning

Val introduces her software development role and explains how her computer science background helped. She describes learning unfamiliar technical and financial concepts from colleagues.

I’m Val, a software developer in Jane Street’s London office. I started here in 2018.

I studied computer science at university, which was good preparation, although I don’t think it’s completely necessary. A developer at Jane Street needs to know some things, such as data structures and algorithms. Whenever I’ve encountered something I didn’t learn at university, people here have been willing to teach me.

I didn’t have any finance experience when I joined, and that was fine. We tend to teach people what they need to know. I knew neither OCaml nor finance coming in; even if you don’t know what a share in a company represents or other financial basics, that’s fine.

02

Internships as a two-way decision

Jane Street aims to give interns a realistic view of the work. Candidates can then decide whether the full-time role suits them.

For internships, we try to put people in situations that show them what working at Jane Street is really like. We don’t think of an internship solely as evaluating a candidate over a summer and deciding whether we want them to work for us. It’s a two-way street: interns also need to understand the full-time job well enough to decide whether it’s something they actually want.

03

Reviewing production code

Val describes code review and the reviewer’s sign-off, called seconding. The author and reviewer share responsibility for the result.

Code review is one of the main ways we make sure production code works. For most code, one person writes it and another reviews it. It also goes through a process called seconding, in which the reviewer signs off that they think the code is good. The reviewer and the author therefore share responsibility.

04

Working across teams

Val works near traders and draws on software from other groups. Informal conversations and social relationships help developers ask questions and cooperate.

As a desktop developer, I work closely with traders, who are my end users. But that doesn’t mean I’m removed from the rest of our development ecosystem: I use libraries and applications from other parts of the firm. It’s completely normal to approach a library’s developer and ask how to use it, or ask whether you can extend it and have them review your code.

We also socialise with other developers and often have lunch together. You might have five developers from different groups talking about general things, not necessarily code. Knowing colleagues socially makes it easier to ask questions, proactively fix things for one another, and want to work together.

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