As a Software Engineer at Qantas, you play a pivotal role in shaping the technological landscape of one of Australia's leading airlines. This position holds significant importance not only within the engineering teams but also across the organization, as it directly impacts operational efficiency, customer experience, and the overall success of Qantas's digital initiatives. Your work will contribute to a range of projects, from enhancing booking systems to developing innovative solutions for flight management and customer service. The complexity and scale of the projects at Qantas provide a unique opportunity for engineers to tackle real-world challenges in a dynamic, fast-paced environment. You will work alongside cross-functional teams, including product managers, designers, and business analysts, to deliver high-quality software solutions that meet the needs of millions of travelers. The role demands a combination of technical expertise, creativity, and a passion for improving technology that supports the airline's mission to provide a seamless travel experience. In this role, you can expect to engage with cutting-edge technologies and methodologies, such as agile development practices, cloud computing, and data analytics. As a, you will not only be instrumental in coding and system design but also in driving innovation and influencing the strategic direction of technology at. Software Engineer Qantas
Phone Screening
reportedInitial discussion about your background and motivations.
What to demonstrate
- Initial discussion about your background and motivations
- Depth in React
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.
Technical Interview
reportedSolve coding challenges or explain your approach to software development.
What to demonstrate
- Solve coding challenges or explain your approach to software development
- Depth in React
How to prepare
- Answer aloud and timed: Explain the concept of RESTful services and how they work.
- Answer aloud and timed: How do you ensure code quality and maintainability in your projects?
Behavioral Interviews
reportedEvaluate your problem-solving skills and teamwork capabilities.
What to demonstrate
- Evaluate your problem-solving skills and teamwork capabilities
- Depth in React
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 interviews above and write down what you would ask to confirm before it.
Case Studies
reportedAssess your problem-solving skills through real-world scenarios.
What to demonstrate
- Assess your problem-solving skills through real-world scenarios
- Depth in React
How to prepare
- Answer aloud and timed: Describe a situation where you had to lead a project under tight deadlines.
- Answer aloud and timed: How do you prioritize tasks when faced with multiple project demands?
PracHub editorial advice for the preparation topics above.
Familiarize Yourself with Qantas' Culture
Understanding the company's values and mission can help you align your answers during the interview.
Practice the STAR Technique
Use the STAR (Situation, Task, Action, Result) method to structure your responses to behavioral questions effectively.
Prepare for Technical Assessments
Brush up on core programming concepts and practice coding challenges to build confidence.
Engage in Mock Interviews
Conduct practice interviews with peers or mentors to refine your responses and improve your presentation.
Choose a category, try a prompt, then open its approach, worked solution or follow-up when you need it.
Write a function to reverse a linked list.
Write a function to reverse a linked list.
Approach
- Restate the input: its shape, its size, and what is guaranteed about it.
- Name the brute-force solution and its complexity before improving on it.
- Choose the data structure from the access pattern, not from familiarity.
- 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 integers, find the two that sum up to a specific target.
Given a list of integers, find the two that sum up to a specific target.
Approach
- Restate the input: its shape, its size, and what is guaranteed about it.
- Name the brute-force solution and its complexity before improving on it.
- Choose the data structure from the access pattern, not from familiarity.
- 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?
Explain the time complexity of your solution.
Explain the time complexity of your solution.
Approach
- Restate the input: its shape, its size, and what is guaranteed about it.
- Name the brute-force solution and its complexity before improving on it.
- Choose the data structure from the access pattern, not from familiarity.
- 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?
Hold a per-tenant active cap against concurrent creates
A tenant on the standard plan may hold at most 50 resources with status='active'. The create handler runs SELECT count(*) FROM resource WHERE tenant_id = $1 AND status = 'active', compares to 50, then inserts. Two creates arrive 3 ms apart on different instances and the tenant lands at 51. Name the anomaly, say whether PostgreSQL 16 READ COMMITTED or REPEATABLE READ prevents it and why, then give an implementation that holds the cap at READ COMMITTED with the exact statements. Finally, say what changes when the cap is 'at most one running export per tenant' on job_run.
Approach
- Name it: write skew. The two transactions read an overlapping set and write disjoint rows, so there is no row-level conflict for the engine to detect and each commit is individually legal.
- Rule out the levels precisely. READ COMMITTED takes a fresh snapshot per statement and takes no lock on the counted rows, so both see 49. PostgreSQL's REPEATABLE READ is snapshot isolation: it removes non-repeatable reads and phantoms within the snapshot but still admits write skew, because the anomaly is not a re-read of a changed row, it is a read of a set that a concurrent transaction invalidates. Only SERIALIZABLE closes it, by tracking the read dependency and aborting one transaction with SQLSTATE 40001 — a guarantee that exists only if the application re-runs the whole transaction from the read.
- Convert the set predicate into a single-row conflict: keep tenant.active_resource_count and run UPDATE tenant SET active_resource_count = active_resource_count + 1 WHERE tenant_id = $1 AND active_resource_count < 50 in the same transaction as the INSERT. Zero affected rows is the cap, returned as 409. The row lock serialises the decision at any isolation level, and contention is bounded to one tenant's row — which is also the fair-scheduling unit, unlike a global counter that would convoy every tenant behind one row.
- State the cost you just took on: a counter is a second source of truth that can drift, so every path that changes status must adjust it inside the same transaction, and a periodic reconciliation has to exist, with resource_revision as the authority for what the count should have been.
Follow-up
- A resource moves from archived back to active. Which statements change, and what breaks if the counter update and the status change land in different transactions?
- The cap becomes plan-dependent and a plan can change mid-month. Where does the number 50 live, and who reads it?
Stop tag and share joins from fanning out a page
resource_tag is (resource_id, tag_id) with PK (resource_id, tag_id); resource_share is (resource_id, shared_with_user_id, permission). The tagged-and-shared listing inner-joins resource to both, filters tenant_id, tag_id = ANY($2) and shared_with_user_id = $3, orders by updated_at DESC and takes 50. Pages come back with fewer than 50 distinct resources and the total in the header is far too high. Explain the row multiplication, rewrite both the page query and the count query so each is correct, and name the index each one needs. PostgreSQL 16.
Approach
- Do the arithmetic against the predicates that are actually there. An inner join emits one row per matching child row, and both joins are filtered: tag_id = ANY($2) admits only the requested tags, shared_with_user_id = $3 admits one user's share rows. So a resource holding three of the requested tags and shared with $3 once yields three rows, not one — the multiplier is its count of matching tags times its share rows for that single user, and that second factor is 1 unless the table admits duplicate (resource_id, shared_with_user_id) pairs. LIMIT 50 then limits rows rather than resources, and COUNT(*) counts pairs — the header is the product, not the population.
- Reject DISTINCT as the fix. It deduplicates after the product has been built, so the planner must materialise and sort the fanned-out set before the LIMIT can apply, and it leaves any SUM or AVG in the same select list wrong.
- Rewrite both filters as semi-joins, keeping resource as the only row source: AND EXISTS (SELECT 1 FROM resource_tag rt WHERE rt.resource_id = r.resource_id AND rt.tag_id = ANY($2)) and the same shape against resource_share. A semi-join stops at the first match per resource and preserves the driving index order, so ORDER BY updated_at DESC, resource_id DESC LIMIT 50 still stops after 50 rows.
- Count with the same predicates and no join at all: SELECT count(*) FROM resource r WHERE r.tenant_id = $1 AND r.status = 'active' AND EXISTS (...) AND EXISTS (...). Nothing multiplies a resource, so the number is the population.
Follow-up
- The filter changes from 'any of these tags' to 'all of these tags'. Rewrite it and state what it costs relative to the ANY form.
- A resource can be shared with the same user twice under different permissions. Does your count change, and should it?
Describe a complex technical challenge you faced and how you resolved it.
Describe a complex technical challenge you faced and how you resolved it.
Approach
- Clarify what is being asked and what a complete answer contains.
- State your assumptions explicitly before working the problem.
- Say what you would check first and why it is the highest-information step.
- Work from the requirement backwards to the design.
Follow-up
- What assumption would you test first?
- How would you know your answer was wrong?
What programming languages are you most proficient in, and why?
What programming languages are you most proficient in, and why?
Approach
- Clarify what is being asked and what a complete answer contains.
- State your assumptions explicitly before working the problem.
- Say what you would check first and why it is the highest-information step.
- Work from the requirement backwards to the design.
Follow-up
- What assumption would you test first?
- How would you know your answer was wrong?
Explain the concept of RESTful services and how they work.
Explain the concept of RESTful services and how they work.
Approach
- Clarify what is being asked and what a complete answer contains.
- State your assumptions explicitly before working the problem.
- Say what you would check first and why it is the highest-information step.
- Work from the requirement backwards to the design.
Follow-up
- What assumption would you test first?
- How would you know your answer was wrong?
How do you ensure code quality and maintainability in your projects?
How do you ensure code quality and maintainability in your projects?
Approach
- Clarify what is being asked and what a complete answer contains.
- State your assumptions explicitly before working the problem.
- Say what you would check first and why it is the highest-information step.
- Work from the requirement backwards to the design.
Follow-up
- What assumption would you test first?
- How would you know your answer was wrong?
How would you approach a situation where a critical bug is found in production?
How would you approach a situation where a critical bug is found in production?
Approach
- Clarify what is being asked and what a complete answer contains.
- State your assumptions explicitly before working the problem.
- Say what you would check first and why it is the highest-information step.
- Work from the requirement backwards to the design.
Follow-up
- What assumption would you test first?
- How would you know your answer was wrong?
If tasked with improving the performance of an application, what steps would you take?
If tasked with improving the performance of an application, what steps would you take?
Approach
- Clarify what is being asked and what a complete answer contains.
- State your assumptions explicitly before working the problem.
- Say what you would check first and why it is the highest-information step.
- Work from the requirement backwards to the design.
Follow-up
- What assumption would you test first?
- How would you know your answer was wrong?
Describe your thought process when debugging a piece of software.
Describe your thought process when debugging a piece of software.
Approach
- Establish what changed and when, before forming any theory.
- Pick a bisection that eliminates candidates whichever way it turns out.
- Check the instrumentation before believing the symptom.
- Separate the trigger from the cause; the deploy is rarely the bug.
Follow-up
- What would you look at first, and what would it rule out?
- How would you tell a cause from a coincidence here?
Built from the rounds and topics Qantas candidates report.
Prepare, practise & reflect
One practical outcome each day. Spend longer where you need it.
0 / 7 done01Map the Qantas loop
- Write out the reported sequence: Phone Screening, Technical Interview, Behavioral Interviews, Case Studies.
- 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 4 reported rounds, with the weakest marked.
02Work React
- Spend the session on React, which Qantas candidates report being tested on.
- Write one worked example in React and time yourself on it.
Deliverable: One timed worked example in React.
03Work Behavioral interviewing
- Spend the session on Behavioral interviewing, which Qantas candidates report being tested on.
- Write one worked example in Behavioral interviewing and time yourself on it.
Deliverable: One timed worked example in Behavioral interviewing.
04Work STAR technique for behavioral answers
- Spend the session on STAR technique for behavioral answers, which Qantas candidates report being tested on.
- Write one worked example in STAR technique for behavioral answers and time yourself on it.
Deliverable: One timed worked example in STAR technique for behavioral answers.
05Answer out loud: Technical / Domain Questions
- Answer aloud, timed: Describe a complex technical challenge you faced and how you resolved it.
- Answer aloud, timed: What programming languages are you most proficient in, and why?
Deliverable: Spoken answers to 2 reported Technical / Domain Questions question(s), under time.
06Answer out loud: Behavioral / Leadership
- Answer aloud, timed: Tell me about a time you had to work with a difficult team member. How did you handle it?
- Answer aloud, timed: Describe a situation where you had to lead a project under tight deadlines.
Deliverable: Spoken answers to 2 reported Behavioral / Leadership question(s), under time.
07Answer out loud: Problem-Solving / Case Studies
- Answer aloud, timed: How would you approach a situation where a critical bug is found in production?
- Answer aloud, timed: If tasked with improving the performance of an application, what steps would you take?
Deliverable: Spoken answers to 2 reported Problem-Solving / Case Studies 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.
Discuss a time when you optimized an existing system or application.
Discuss a time when you optimized an existing system or application.
Approach
- Pick a story where you made the decision, not one where you watched it.
- State the situation in two sentences and spend the rest on the reasoning.
- Give the blast radius: what could have broken, and what you measured.
- Name the disagreement and how you resolved it with evidence.
Follow-up
- What would you do differently if you ran that again?
- How did you know your change caused the improvement?
Tell me about a time you had to work with a difficult team member. How did you handle it?
Tell me about a time you had to work with a difficult team member. How did you handle it?
Approach
- Pick a story where you made the decision, not one where you watched it.
- State the situation in two sentences and spend the rest on the reasoning.
- Give the blast radius: what could have broken, and what you measured.
- Name the disagreement and how you resolved it with evidence.
Follow-up
- What would you do differently if you ran that again?
- How did you know your change caused the improvement?
Describe a situation where you had to lead a project under tight deadlines.
Describe a situation where you had to lead a project under tight deadlines.
Approach
- Pick a story where you made the decision, not one where you watched it.
- State the situation in two sentences and spend the rest on the reasoning.
- Give the blast radius: what could have broken, and what you measured.
- Name the disagreement and how you resolved it with evidence.
Follow-up
- What would you do differently if you ran that again?
- How did you know your change caused the improvement?
How do you prioritize tasks when faced with multiple project demands?
How do you prioritize tasks when faced with multiple project demands?
Approach
- Pick a story where you made the decision, not one where you watched it.
- State the situation in two sentences and spend the rest on the reasoning.
- Give the blast radius: what could have broken, and what you measured.
- Name the disagreement and how you resolved it with evidence.
Follow-up
- What would you do differently if you ran that again?
- How did you know your change caused the improvement?
Give an example of how you contributed to a team’s success.
Give an example of how you contributed to a team’s success.
Approach
- Pick a story where you made the decision, not one where you watched it.
- State the situation in two sentences and spend the rest on the reasoning.
- Give the blast radius: what could have broken, and what you measured.
- Name the disagreement and how you resolved it with evidence.
Follow-up
- What would you do differently if you ran that again?
- How did you know your change caused the improvement?
How do you handle feedback and criticism from peers or managers?
How do you handle feedback and criticism from peers or managers?
Approach
- Pick a story where you made the decision, not one where you watched it.
- State the situation in two sentences and spend the rest on the reasoning.
- Give the blast radius: what could have broken, and what you measured.
- Name the disagreement and how you resolved it with evidence.
Follow-up
- What would you do differently if you ran that again?
- How did you know your change caused the improvement?
- 01
Discuss a time when you optimized an existing system or application.
- 02
Tell me about a time you had to work with a difficult team member. How did you handle it?
- 03
Describe a situation where you had to lead a project under tight deadlines.
- 04
How do you prioritize tasks when faced with multiple project demands?
How difficult are the interviews at Qantas?
The interview difficulty can vary by team and role, but generally, candidates report a mix of technical and behavioral questions. Preparation is crucial, as demonstrating both your technical knowledge and cultural fit is essential for success.
Qantas Software Engineer candidate reports ↗What differentiates successful candidates?
Successful candidates often showcase a strong grasp of technical concepts along with effective communication and problem-solving skills. Additionally, a clear alignment with Qantas' values and culture can set you apart.
Qantas Software Engineer candidate reports ↗What is the typical timeline from application to offer?
The process can take several weeks to a few months, depending on the number of candidates and the specific team. Candidates are encouraged to stay engaged and follow up for updates during the process.
Qantas Software Engineer candidate reports ↗Is remote work an option for this role?
Qantas is increasingly embracing flexible work arrangements. However, specifics will depend on team needs and project requirements. Discuss expectations during your interviews.
Qantas Software Engineer candidate reports ↗What topics does Qantas test in interviews?
Qantas interviews most often cover Problem Solving, Interview Process Management, Stakeholder Communication, Behavioral Interviewing, and Communication Skills. The exact emphasis depends on the specific role you apply for.
Qantas 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.
- 01Qantas Software Engineer candidate reports ↗
Company-reported rounds, questions and FAQ.
Candidate reports · Accessed 2026-09-22 - 02PracHub Software Engineer practice ↗
PracHub practice material, not company-reported.
PracHub page · Accessed 2026-09-22 - 03PracHub preparation framework ↗
PracHub preparation guidance.
PracHub page · Accessed 2026-09-22
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