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Growth · Software Engineer Interview Guide

Applies via Proprietary

How to Pass the Adfin Software Engineer Interview in 2026

The Adfin DNA (TL;DR)

Adfin highly values candidates who demonstrate strong analytical problem-solving skills, a deep understanding of financial workflows or data, and an ability to navigate complex, regulated environments. They seek individuals who are proactive, detail-oriented, and can clearly articulate their thought process and solutions.

The Adfin 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 Adfin interview outcomes, avoid these common traps:

  • Not demonstrating an understanding of Adfin's business model or growth strategies.
  • Focusing only on the 'what' (the technology) and not the 'how' (the learning process).
  • Underestimating the complexity of distributed message queues and stream processing.
  • Choosing a batch processing system for real-time requirements.

Test Yourself: Real Adfin Questions

Three real prompts pulled from our database.

Type · algorithms

A/B testing is crucial for growth. You are given two sets of user data, 'control' and 'treatment', each with a list of conversion events. Write a function to determine if the conversion rate difference is statistically significant using a standard hypothesis test (e.g., z-test for proportions).

Type · Past Experience

Tell me about a time you had to influence a team or stakeholder who was resistant to your idea or proposed direction. How did you approach it, and what was the outcome?

Type · Ownership

Tell me about a time you took initiative to solve a problem that wasn't explicitly part of your job description. What was the situation, what did you do, and what was the outcome?

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Adfin 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 joining Adfin, a fintech company focused on growth and user acquisition, as a Software Engineer?
2

Coding Screen

3
  1. 2

    Type · data-structures

    Given a stream of financial transactions, implement a data structure that can efficiently calculate the moving average of the transaction amounts over the last N transactions.
  2. 3

    Type · algorithms

    A/B testing is crucial for growth. You are given two sets of user data, 'control' and 'treatment', each with a list of conversion events. Write a function to determine if the conversion rate difference is statistically significant using a standard hypothesis test (e.g., z-test for proportions).
  3. + 1 more questions in this round (sign up to unlock)
3

System Design

3
  1. 4

    Type · api-design

    Design an API for Adfin's core transaction processing service. Consider aspects like idempotency, rate limiting, request/response formats, and error handling for a high-throughput fintech environment.
  2. 5

    Type · scalability

    Adfin's user base is growing rapidly. How would you design a system to handle a 10x increase in concurrent users accessing their financial dashboards, ensuring low latency and high availability?
  3. + 1 more questions in this round (sign up to unlock)
4

Onsite Coding

3
  1. 6

    Type · debugging

    A critical bug is reported: users are sometimes seeing incorrect balances on their dashboard. The backend logs show intermittent `NaN` values being returned for balance calculations. Debug this issue and propose a fix. Assume the calculation involves multiple microservices.
  2. 7

    Type · algorithms

    Implement a function to detect fraudulent transactions based on a set of rules. For example, flag transactions exceeding a certain amount, occurring in rapid succession from the same user, or originating from a known suspicious IP address. Optimize for performance as transaction volume is high.
  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 team or stakeholder who was resistant to your idea or proposed direction. How did you approach it, and what was the outcome?
  2. 9

    Type · Ownership

    Tell me about a time you took ownership of a problem or project that wasn't explicitly assigned to you. What was the situation, and what was the outcome?
  3. + 8 more questions in this round (sign up to unlock)

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Interview tracks at Adfin

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

Adfin SWEs are evaluated on their proficiency in building robust, scalable, and secure financial systems, often involving real-time data processing and complex algorithms. Expect deep dives into system design for high-transaction fintech platforms and coding challenges focused on data integrity.

algorithms

A/B testing is crucial for growth. You are given two sets of user data, 'control' and 'treatment', each with a list of conversion events. Write a function to determine if the conversion rate difference is statistically significant using a standard hypothesis test (e.g., z-test for proportions).

Past Experience

Tell me about a time you had to influence a team or stakeholder who was resistant to your idea or proposed direction. How did you approach it, and what was the outcome?

+ 1 more

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Compare Adfin with similar employers

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

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