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Growth · Software Engineer Interview Guide

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How to Pass the Qonto Software Engineer Interview in 2026

The Qonto DNA (TL;DR)

Qonto's commitment to empowering businesses drives its assessment of candidates' capacity to simplify complex financial workflows, particularly in areas like 'Tools Bookkeeping'. They look for individuals who can articulate how their contributions directly enhance the user experience and operational efficiency for SMBs.

The Qonto Interview Loop

Your onsite loop will typically consist of 5 rounds.

  1. 1

    Round 1

    Recruiter Screen
    Motivation, role fit, logistics.
  2. 2

    Round 2

    Coding Screen
    LeetCode-medium algorithmic problems under time pressure.
  3. 3

    Round 3

    System Design
    Distributed systems, trade-offs at scale, architecture under constraints.
  4. 4

    Round 4

    Onsite Coding
    LeetCode-hard, debugging, code clarity, edge cases.
  5. 5

    Round 5

    Behavioral / Leadership
    Past evidence of ownership, influence, resolving conflict.

The Danger Zone: Top Reasons Candidates Fail

Based on our database of Qonto interview outcomes, avoid these common traps:

  • Not providing specific examples of communication or data used
  • Incorrectly filtering for positive balances.
  • Describing a situation where the PM was passive or dictatorial
  • Failing to mention how trade-offs or disagreements were resolved

Test Yourself: Real Qonto Questions

Three real prompts pulled from our database.

Type · Past Experience

Tell me about a time you had to influence a stakeholder who disagreed with your product direction. How did you approach it, and what was the outcome?

Type · Algorithmic

Given a list of bank transactions, each with a timestamp, amount, and category, write a function to calculate the total spending for each category within a given date range. Optimize for performance.

Type · Motivation

Why are you interested in Qonto, and what specifically about our SWE role excites you?

+ many more questions, signals, and worked examples

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Qonto Interview Question Bank

A sample from our database, grouped by round. Sign up to see the full set.

9 of 20 questions shown

1

Recruiter Screen

1
  1. 1

    Type · Motivation

    Why are you interested in Qonto, and what specifically about our SWE role excites you?
2

Coding Screen

3
  1. 2

    Type · Algorithmic

    Given a list of bank transactions, each with a timestamp, amount, and category, write a function to calculate the total spending for each category within a given date range. Optimize for performance.
  2. 3

    Type · Algorithmic

    Implement a function that takes a list of user IDs and returns a list of unique user IDs that have performed more than K transactions in the last 30 days. Assume you have access to a `getUserTransactions(userId, startDate, endDate)` function.
  3. + 1 more questions in this round (sign up to unlock)
3

System Design

3
  1. 4

    Type · System Design

    Design a system to detect and flag potentially fraudulent bank transfers in real-time for Qonto users. Consider the data sources, processing pipeline, and alerting mechanisms.
  2. 5

    Type · System Design

    Design a notification service for Qonto that can send various types of notifications (e.g., successful payment, low balance, new feature announcement) to users via email, SMS, and in-app push notifications. Consider scalability and reliability.
  3. + 1 more questions in this round (sign up to unlock)
4

Onsite Coding

3
  1. 6

    Type · Algorithmic

    Write a function to process a stream of incoming bank account balance updates. The function should maintain the current balance for each account and be able to answer queries about the balance at a specific point in time in the past. Assume updates are not necessarily ordered by time.
  2. 7

    Type · Debugging

    A user reports that their recent payments are not showing up in their transaction history. Here is a simplified version of the code responsible for processing and displaying transactions. Find and fix the bug.
  3. + 1 more questions in this round (sign up to unlock)
5

Behavioral / Leadership

10
  1. 8

    Type · Past Experience

    Tell me about a time you had to influence a stakeholder who disagreed with your product direction. How did you approach it, and what was the outcome?
  2. 9

    Type · Collaboration

    Tell me about a time you had to work closely with engineers or designers on a complex feature. How did you ensure effective collaboration and alignment?
  3. + 8 more questions in this round (sign up to unlock)

Unlock the full Qonto question bank

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Interview tracks at Qonto

How Qonto's DNA translates across functions. Pick your role.

Compare Qonto with similar employers

Same DNA, different bar. Browse the closest companies in our database and see how their loops differ.

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