DAZN · Software Engineer
Updated · 2026-10-02

DAZN Software Engineer
Interview Guide

THE 60-SECOND BRIEF

As a Software Engineer at DAZN, you are at the heart of the world’s leading sports streaming platform. Your work directly impacts how millions of fans experience live sports, requiring you to build and maintain systems that handle massive concurrency, low-latency video streaming, and highly available architecture. You aren't just writing code; you are solving complex challenges related to scale, real-time data processing, and distributed systems to ensure a seamless viewing experience under intense load. The role demands a blend of technical depth and product intuition. Whether you are working on the backend infrastructure that powers global broadcasts, optimizing front-end performance for a smooth user interface, or designing scalable microservices, your contributions are critical to DAZN’s growth.

This guide is scoped to a Software Engineer candidate at DAZN.

DAZN candidates report 5 rounds over 4-6 weeks. The stages below are what candidates describe, not a published process.

Data Structures & Algorithms (DSA)Coding Interviews / Problem SolvingSQL

23 min read

Browse Software Engineer questions

See the practice prompts

19Practice promptsAcross five skill areas

As a Software Engineer at DAZN, you are at the heart of the world’s leading sports streaming platform. Your work directly impacts how millions of fans experience live sports, requiring you to build and maintain systems that handle massive concurrency, low-latency video streaming, and highly available architecture. You aren't just writing code; you are solving complex challenges related to scale, real-time data processing, and distributed systems to ensure a seamless viewing experience under intense load. The role demands a blend of technical depth and product intuition. Whether you are working on the backend infrastructure that powers global broadcasts, optimizing front-end performance for a smooth user interface, or designing scalable microservices, your contributions are critical to DAZN’s growth. You will collaborate with cross-functional teams, including product managers and operations, to deliver features that keep the platform competitive, reliable, and user-centric. ##### Tip DAZN values practical problem-solving over rote memorization. During your interviews, focus on explaining your thought process clearly, even if you are unsure of the exact syntax or a specific framework keyword.

01

Recruiter Screening

reported

Initial screening to align on your experience and expectations.

What to demonstrate

  • Initial screening to align on your experience and expectations
  • Depth in Data Structures & Algorithms (DSA)

How to prepare

  • Be able to walk your CV end to end in two minutes, and say why this company specifically.
  • Have your salary expectations, notice period and location constraints ready, and ask for the rest of the loop in writing.
DAZN Software Engineer candidate reports ↗
02

Online Assessments

reported

Assessment tasks to evaluate your technical skills.

What to demonstrate

  • Assessment tasks to evaluate your technical skills
  • Depth in Data Structures & Algorithms (DSA)

How to prepare

  • Answer aloud and timed: What are the key differences between SQL and NoSQL databases, and when would you choose one over the other?
  • Answer aloud and timed: Explain core concepts in Operating Systems and Computer Networks (e.g., latency, throughput, TCP/IP).
DAZN Software Engineer candidate reports ↗
03

Machine Coding Tasks

reported

Practical coding tasks to demonstrate your programming abilities.

What to demonstrate

  • Practical coding tasks to demonstrate your programming abilities
  • Depth in Data Structures & Algorithms (DSA)

How to prepare

  • Answer aloud and timed: What is the difference between Sharding and Replication in database design?
  • Answer aloud and timed: Implement a solution for the Longest Increasing Subsequence problem.
DAZN Software Engineer candidate reports ↗
04

Technical Discussions

reported

In-depth technical discussions with engineering managers or senior developers.

What to demonstrate

  • In-depth technical discussions with engineering managers or senior developers
  • Depth in Data Structures & Algorithms (DSA)

How to prepare

  • Answer aloud and timed: Write a function to check if a string is a Palindrome.
  • Answer aloud and timed: Given a list of lists (e.g., color: [ORANGE, RED]), how would you map inputs to their respective categories?
DAZN Software Engineer candidate reports ↗
05

Behavioral Fit Assessment

reported

Evaluation of your fit within the company culture and team.

What to demonstrate

  • Evaluation of your fit within the company culture and team
  • Depth in Data Structures & Algorithms (DSA)

How to prepare

  • Prepare three examples from your own work, each with a decision you made and an outcome you can quantify.
  • Re-read the description of the behavioral fit assessment above and write down what you would ask to confirm before it.
DAZN Software Engineer candidate reports ↗

PracHub editorial advice for the preparation topics above.

01

Show Your Thought Process

Always talk through your code. Interviewers want to see how you break down problems and handle constraints.

02

Know Your Resume

Be prepared to explain every project you listed. If you mention a technology, expect a question about how you used it.

03

Prepare for Behavioral Rounds

Be ready to share examples of how you handled conflict, technical challenges, or tight deadlines.

04

Focus on Foundations

If you are a beginner, focus on mastering the basics of JavaScript, Node.js, and databases, as these are frequent evaluation points.

Choose a category, try a prompt, then open its approach, worked solution or follow-up when you need it.

16 technical prompts0 include a worked solution

How do you handle asynchronous operations in JavaScript (Promises, async/await)?

medium
Technical Fundamentals & Core Subjects

How do you handle asynchronous operations in JavaScript (Promises, async/await)?

Approach
  1. Say what the runtime actually does before reasoning about the code.
  2. Name what is shared across threads and what owns each piece of state.
  3. Identify the window where an invariant is briefly untrue.
  4. Distinguish a value from a reference to it, and say which one you handed out.
Follow-up
  • What happens if two callers reach this at the same time?
  • Where could this allocate more than you expect?

Implement a solution for the Longest Increasing Subsequence problem.

medium
Coding & Problem Solving

Implement a solution for the Longest Increasing Subsequence problem.

Approach
  1. Restate the input: its shape, its size, and what is guaranteed about it.
  2. Name the brute-force solution and its complexity before improving on it.
  3. Choose the data structure from the access pattern, not from familiarity.
  4. State the target complexity and say which constraint rules the naive version out.
Follow-up
  • How does this change if the input no longer fits in memory?
  • What is the worst case, and how likely is it on real data?

Write a function to check if a string is a Palindrome.

medium
Coding & Problem Solving

Write a function to check if a string is a Palindrome.

Approach
  1. Restate the input: its shape, its size, and what is guaranteed about it.
  2. Name the brute-force solution and its complexity before improving on it.
  3. Choose the data structure from the access pattern, not from familiarity.
  4. State the target complexity and say which constraint rules the naive version out.
Follow-up
  • How does this change if the input no longer fits in memory?
  • What is the worst case, and how likely is it on real data?

Given a list of lists (e.g., color: [ORANGE, RED]), how would you map inputs to their respective categories?

medium
Coding & Problem Solving

Given a list of lists (e.g., color: [ORANGE, RED]), how would you map inputs to their respective categories?

Approach
  1. Restate the input: its shape, its size, and what is guaranteed about it.
  2. Name the brute-force solution and its complexity before improving on it.
  3. Choose the data structure from the access pattern, not from familiarity.
  4. State the target complexity and say which constraint rules the naive version out.
Follow-up
  • How does this change if the input no longer fits in memory?
  • What is the worst case, and how likely is it on real data?

How would you optimize a given code snippet for better performance or memory usage?

medium
Coding & Problem Solving

How would you optimize a given code snippet for better performance or memory usage?

Approach
  1. Say what the runtime actually does before reasoning about the code.
  2. Name what is shared across threads and what owns each piece of state.
  3. Identify the window where an invariant is briefly untrue.
  4. Distinguish a value from a reference to it, and say which one you handed out.
Follow-up
  • What happens if two callers reach this at the same time?
  • Where could this allocate more than you expect?

Can you explain your approach to handling exceptions and retries in a live coding environment?

medium
Coding & Problem Solving

Can you explain your approach to handling exceptions and retries in a live coding environment?

Approach
  1. Restate the input: its shape, its size, and what is guaranteed about it.
  2. Name the brute-force solution and its complexity before improving on it.
  3. Choose the data structure from the access pattern, not from familiarity.
  4. State the target complexity and say which constraint rules the naive version out.
Follow-up
  • How does this change if the input no longer fits in memory?
  • What is the worst case, and how likely is it on real data?

How would you handle high concurrency during a major live sports event?

medium
System Design & Architecture

How would you handle high concurrency during a major live sports event?

Approach
  1. Say what the runtime actually does before reasoning about the code.
  2. Name what is shared across threads and what owns each piece of state.
  3. Identify the window where an invariant is briefly untrue.
  4. Distinguish a value from a reference to it, and say which one you handed out.
Follow-up
  • What happens if two callers reach this at the same time?
  • Where could this allocate more than you expect?

Built from the rounds and topics DAZN candidates report.

Small steps. Visible outcomes.0 / 7 completed
ONE WEEK · YOUR PACE

Prepare, practise & reflect

One practical outcome each day. Spend longer where you need it.

0 / 7 done
01Map the DAZN loop
  • Write out the reported sequence: Recruiter Screening, Online Assessments, Machine Coding Tasks, Technical Discussions, Behavioral Fit Assessment.
  • For each round, write one sentence on what it is judging, from the description above, and mark the one you are least ready for.

Deliverable: A one-page map of the 5 reported rounds, with the weakest marked.

02Work Data Structures & Algorithms (DSA)
  • Spend the session on Data Structures & Algorithms (DSA), which DAZN candidates report being tested on.
  • Write one worked example in Data Structures & Algorithms (DSA) and time yourself on it.

Deliverable: One timed worked example in Data Structures & Algorithms (DSA).

03Work Coding Interviews / Problem Solving
  • Spend the session on Coding Interviews / Problem Solving, which DAZN candidates report being tested on.
  • Write one worked example in Coding Interviews / Problem Solving and time yourself on it.

Deliverable: One timed worked example in Coding Interviews / Problem Solving.

04Work SQL
  • Spend the session on SQL, which DAZN candidates report being tested on.
  • Write one worked example in SQL and time yourself on it.

Deliverable: One timed worked example in SQL.

05Answer out loud: Technical Fundamentals & Core Subjects
  • Answer aloud, timed: Explain the Event Loop and the Node.js architecture.
  • Answer aloud, timed: How do you handle asynchronous operations in JavaScript (Promises, async/await)?

Deliverable: Spoken answers to 2 reported Technical Fundamentals & Core Subjects question(s), under time.

06Answer out loud: Coding & Problem Solving
  • Answer aloud, timed: Implement a solution for the Longest Increasing Subsequence problem.
  • Answer aloud, timed: Write a function to check if a string is a Palindrome.

Deliverable: Spoken answers to 2 reported Coding & Problem Solving question(s), under time.

07Answer out loud: System Design & Architecture
  • Answer aloud, timed: Design an architecture for a 1-minute active e-commerce platform.
  • Answer aloud, timed: How would you handle high concurrency during a major live sports event?

Deliverable: Spoken answers to 2 reported System Design & Architecture question(s), under time.

Expand any day for tasks and deliverables. Your progress is saved on this device.

Behavioural rounds judge the decision you made and what it cost.

Estimate work you have never done and defend the range

hard
estimationbackfillsexpand-contract

You are asked to estimate a change you have never attempted: add a column to a 100-million-row table, populate it, move reads across, and drop the old shape. Give a range with the assumptions that generate it, including batch size, the signal your backfill throttles on, and wall-clock hours, and name the three unknowns that would move the number most. Then describe a real estimate you gave under comparable ignorance: how you expressed its uncertainty, what you committed to, and how wrong you turned out to be.

Approach
  1. Decompose into independently deployable steps before estimating anything: add the column nullable, write both shapes, backfill in batches, verify, move reads, stop writing the old shape, drop it. That is four deploys spread over days, and the calendar estimate is dominated by them rather than by the loop's runtime.
  2. Do the arithmetic aloud for the part that has arithmetic in it: batch size times number of batches times per-batch duration, at a write rate the primary can absorb alongside roughly 1.2k writes per second of production traffic. The loop is throttled by replication lag and lock waits, not by how fast it can issue statements.
  3. Price the schema step by its lock rather than its statement duration. In PostgreSQL an ALTER TABLE taking ACCESS EXCLUSIVE waits for every open transaction on that table while later queries queue behind it, so a millisecond change issued during a thirty-second analytics query stalls that table for thirty seconds. Adding a nullable column with a non-volatile default avoids a rewrite from version 11; a new index wants CREATE INDEX CONCURRENTLY, which cannot run inside a transaction block and leaves an invalid index behind if it fails.
  4. Express the answer as a range whose endpoints each trace to a stated assumption, then name the cheapest experiment that collapses it, which is almost always running one real batch against the real table and multiplying.
Follow-up
  • How do you verify the backfill genuinely finished, given rows written by production traffic while it ran?
  • Where does the backfill resume from after a worker is killed mid-batch, and what makes that resume point trustworthy?

Ship under a deadline and bound the debt you chose

medium
paginationtechnical debttradeoffs

You have four days to ship a tenant-facing listing endpoint. The version you would defend uses keyset pagination over (tenant_id, status, updated_at DESC, resource_id DESC); the version you can finish uses LIMIT/OFFSET with no matching index. Describe a deadline call you actually made of this shape: what you shipped, what you knowingly deferred, how you bounded the damage with a mechanism rather than an intention, and the specific numeric condition that would force the follow-up. Name who you told and where you wrote it down.

Approach
  1. Name the deferred failure precisely instead of calling it slow. OFFSET n makes the database produce and discard n rows, so cost grows with page depth; without an index matching the sort, every matching row is read and sorted before the limit applies; and rows inserted between two page fetches shift across the boundary so items are skipped or repeated with nothing in the response to signal it.
  2. Bound the blast radius with something mechanical rather than a promise: cap maximum page depth, cap page size, restrict the endpoint to one internal caller, or keep it behind a flag. State which failure each cap removes and which it leaves standing.
  3. Attach a number to the trigger and wire it to an alarm: the first tenant crossing N resources, or the endpoint's p99 crossing its share of the 400 ms budget, so the debt announces itself instead of waiting to be remembered.
  4. Write it where the next engineer looks, which is the code and the ticket, not a chat message: what was deferred, why, the cap, and the trigger.
Follow-up
  • At what page depth does the offset version breach your latency budget, given your page size and row counts?
  • What breaks first when you switch to keyset pagination later, and what does a client holding an old page token see?

Tell callers you do not own that their integration breaks

medium
deprecationcompatibilitystakeholders

A field in a write endpoint's response must change shape. You own the endpoint; you do not own the four internal callers or the outbound webhook consumers who read it. Describe a deprecation you were responsible for: what you shipped first, how you established who was actually reading the field, the window you gave and what set its length, what you did about the consumer who never moved, and how you decided removal was safe. Name the signal you used, not the announcement you sent.

Approach
  1. Establish the reader set empirically rather than from a wiki of owners: per-field usage counters keyed by principal, or access logs attributed to a consumer. State the blind spot of whichever you pick, since a consumer that reads the field only on a monthly job will not appear in a week of logs.
  2. Ship additive first. Populate the new field alongside the old one so no reader is forced to move, which is also what keeps a rolling deploy safe, because old and new instances answer the same requests at the same time and a rollback must still find the old shape present.
  3. Set the window from the slowest legitimate consumer's release cadence, not from your calendar, and decide separately what to do for a consumer with no release process at all, such as an external webhook endpoint you can only email.
  4. Convert silence into evidence before you rely on it: a short, low-traffic removal window that makes a still-dependent consumer fail visibly and loudly while you are watching, rather than at three in the morning after you have moved on.
Follow-up
  • How would you detect a consumer that reads the field only during a monthly export?
  • One caller refuses to move and has a commercial relationship behind it. What changes in your plan and what does not?
  • 01

    You are asked to estimate a change you have never attempted: add a column to a 100-million-row table, populate it, move reads across, and drop the old shape. Give a range with the assumptions that generate it, including batch size, the signal your backfill throttles on, and wall-clock hours, and name the three unknowns that would move the number most. Then describe a real estimate you gave under comparable ignorance: how you expressed its uncertainty, what you committed to, and how wrong you turned out to be.

  • 02

    You have four days to ship a tenant-facing listing endpoint. The version you would defend uses keyset pagination over (tenant_id, status, updated_at DESC, resource_id DESC); the version you can finish uses LIMIT/OFFSET with no matching index. Describe a deadline call you actually made of this shape: what you shipped, what you knowingly deferred, how you bounded the damage with a mechanism rather than an intention, and the specific numeric condition that would force the follow-up. Name who you told and where you wrote it down.

  • 03

    A field in a write endpoint's response must change shape. You own the endpoint; you do not own the four internal callers or the outbound webhook consumers who read it. Describe a deprecation you were responsible for: what you shipped first, how you established who was actually reading the field, the window you gave and what set its length, what you did about the consumer who never moved, and how you decided removal was safe. Name the signal you used, not the announcement you sent.

PracHub preparation framework ↗
Is the interview process difficult?

It is generally considered average to challenging. The focus is on your ability to apply fundamentals to real-world scenarios rather than just solving abstract puzzles.

DAZN Software Engineer candidate reports ↗
How much time should I spend preparing?

Dedicate enough time to review your own projects in depth, as these are frequent topics of discussion. Brush up on your core language concepts and basic system design principles.

DAZN Software Engineer candidate reports ↗
What is the culture like at DAZN?

DAZN is a fast-paced environment. They value professionalism, technical curiosity, and the ability to work well within a collaborative team. ##### Tip Compensation for senior roles can be highly competitive. When discussing salary, research the market rate for your specific location and be prepared to discuss your expectations clearly based on your value and experience.

DAZN Software Engineer candidate reports ↗
How hard are DAZN Software Engineer interviews, based on candidate reports?

That suggests steady preparation without assuming everything will be either very easy or extremely technical from the start.

DAZN Software Engineer candidate reports ↗
What are the interview rounds for DAZN Software Engineer roles, and how does the loop run?

The process typically starts with a recruiter screening to align on your experience and expectations. After that, you can expect online assessments, machine coding tasks, technical discussions with engineering managers or senior developers, and a final behavioral fit assessment.

DAZN Software Engineer candidate reports ↗
What topics does DAZN test for Software Engineer interviews?

Expect a mix of coding and core systems topics, including Data Structures and Algorithms, coding interviews or problem solving, and SQL. System design and database fundamentals also show up, along with areas like scalability, microservices, and concurrency. The guide also highlights practical problem-solving, including explaining your thought process clearly during the interview.

DAZN Software Engineer candidate reports ↗
What should I prioritize when preparing for DAZN Software Engineer interviews?

Prioritize being able to articulate the “why” behind your coding and design decisions, because interviewers probe for depth in your specific tech stack and past projects. For technical prep, focus on core foundations that match the role themes: async behavior, concurrency, SQL and DBMS concepts, and system design for scalability and high availability. For the interview format itself, be ready to start by clarifying requirements, outlining your strategy, and then moving into implementation.

DAZN Software Engineer candidate reports ↗
What coding questions are publicly listed for DAZN Software Engineer interviews?

Public sample questions include “String Permutation” and “Missing Minimum in Array.” These align with the broader emphasis on Data Structures and Algorithms and coding interview style problem solving.

DAZN Software Engineer candidate reports ↗
Sources & methodology 3 sources ↗

No official company page is cited. Rounds and questions come from candidate reports and PracHub editorial material; each source shows the date it was read.