Bloomberg London New Grad SWE Interview: Coding, System Design, Behavioral

BloombergSoftware Engineer, New Grad 2021·London·Interviewed February 2021Offer

Updated July 17, 2026

The candidate, a new graduate with a BEng in Computer Science from a top-10 school in Asia, had two prior summer internships (including one at a fast-growing hedge fund) but no big-name internship on the resume. A recruiter reached out through LinkedIn; the candidate then applied through Bloomberg's own careers page and received an interview invitation a few days later for the Software Engineer New Grad 2021 role in London.

The process ran four rounds spread across several months, from a first coding interview in November through a behavioral round in February, all conducted over video call. The candidate described the questions throughout as standard and the interviewers as businesslike at first but warmer once technical competence was demonstrated. Bloomberg's HR team turned around updates within one to two working days at each stage, and an offer followed the final round within two business days.

How the process went

Sourcing and application
A Bloomberg recruiter reached out via LinkedIn. The candidate applied through Bloomberg's website and received an interview invitation a few days later.
First coding round (November)
One software engineer conducted a two-question coding interview. The candidate coded in Python and was not expected to run the code or produce perfect syntax.
Second coding round (December)
Two software engineers conducted a second two-question coding interview, again focused on problem-solving and complexity analysis rather than working code.
System design round (January)
A senior engineer led a single system design problem, probing the candidate's reasoning on data modeling, APIs, and scaling trade-offs.
Behavioral round (February)
An HR representative and a senior engineer jointly ran a non-technical round covering teamwork scenarios, motivation for joining Bloomberg, and any competing offers.
Outcome
The candidate received an email about two working days after the behavioral round confirming Bloomberg wanted to extend an offer.

First Coding Round

Data structures and algorithms, two problems with one interviewer

A variation of the 'Consecutive Characters' problem
Number of Islands

Solutions were typed in Python; running the code or having perfect syntax was not required.

The candidate walked through a full solution verbally before writing code, and was slower on the second problem but stayed calm and narrated the approach throughout.

The interviewer asked for time and space complexity on each question.

Second Coding Round

Data structures and algorithms with two interviewers

Design Underground System
Populating Next Right Pointers in Each Node

The interviewer also asked the candidate to justify why the algorithm for the second question must process nodes strictly left to right.

The candidate again described the full solution before coding and fixed minor bugs quickly once prompted.

System Design Round

Designing a video download-and-watch platform with a senior engineer

Design a platform where users can download videos to watch, which also remembers what users have watched, tracks viewing progress, and recommends videos to new and existing users
How does your recommendation system work?
You mentioned pre-computing a ranked list of recommended videos per user, but there could be millions of users and tens of thousands of videos — do you store an ordered list per user, and what problems does that raise?
How do you handle unstable internet connections while a user is downloading a video?

The candidate started by identifying what data needed to persist, sketched a database schema (e.g., a USER table and a VIDEO table), then listed key APIs such as login, recommendation, and download before drawing a rough architecture diagram.

The candidate's approach was to design something that could fit on a single machine first, then discuss caching for performance, and only then consider multi-machine scaling.

The candidate found it useful to ask the interviewer clarifying questions about data freshness and accuracy requirements rather than assuming them.

Behavioral Round

Non-technical conversation with HR and a senior engineer

What would you do if you and a coworker had different opinions on how to solve a problem?
Why Bloomberg?
Do you have any competing offers?

No technical questions were asked in this round.

Key takeaways

Narrate a complete solution approach before writing any code; explaining reasoning clearly mattered even when execution had minor bugs or was slower than ideal.
In system design, start with a version that fits on a single machine, add caching next, and only then discuss multi-machine scaling — jumping straight to scaling was not what this interviewer was looking for.
Ask clarifying questions in system design rounds (e.g., how fresh or accurate data needs to be) instead of assuming requirements and over-engineering a solution.
Be ready to justify correctness, not just complexity — this candidate credited a school algorithms course focused on proof-writing more than LeetCode volume for handling 'why does this work' follow-ups.
A less prestigious internship history or an average GPA did not block this candidate from an offer — in their own words, GPA isn't everything, so it is worth believing in yourself and going for it.

Practice a Bloomberg interview

Rehearse out loud against the kinds of questions in this story — with an AI interviewer that asks follow-ups.

Practice this interview

Source

The questions and process facts come from the candidate's public write-up, linked below. The retelling above is our own summary.

Candidate's public write-up on LeetCode Discuss