As a Software Engineer at Air Apps, you will play a pivotal role in shaping the digital products that define our users' experiences. Your work will directly influence the development of applications that are not only functional but also engaging and user-friendly. This position is vital in driving innovation, as you will collaborate with cross-functional teams to create solutions that meet the evolving needs of our customers. At Air Apps, you will be involved in projects that span various domains, from mobile applications to web-based platforms, contributing to products that serve a wide range of users. The complexities of these products require a strong technical foundation, creative problem-solving skills, and a commitment to quality. This role offers the opportunity to tackle significant challenges while working in a collaborative and supportive environment, making your contributions not only impactful but also rewarding.
Phone Screen
reportedInitial phone screen with a recruiter to evaluate your background and role fit.
What to demonstrate
- Initial phone screen with a recruiter to evaluate your background and role fit
- Depth in Programming (general problem solving)
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 Interviews
reportedInterviews that may include coding challenges and discussions about past projects.
What to demonstrate
- Interviews that may include coding challenges and discussions about past projects
- Depth in Programming (general problem solving)
How to prepare
- Answer aloud and timed: Can you describe the SOLID principles of software development?
- Answer aloud and timed: How would you optimize a slow-running SQL query?
Behavioral Questions
reportedAssessment of teamwork and adaptability through behavioral questions.
What to demonstrate
- Assessment of teamwork and adaptability through behavioral questions
- Depth in Programming (general problem solving)
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 questions above and write down what you would ask to confirm before it.
PracHub editorial advice for the preparation topics above.
Practice Coding Questions
Regularly solve coding challenges to build confidence and fluency in your programming skills.
Understand the Company Culture
Research Air Apps to ensure your values align with the company’s mission and work environment.
Prepare Questions for Interviewers
Have thoughtful questions ready to demonstrate your interest and engagement during interviews.
Be Ready to Discuss Past Experiences
Prepare concise stories that highlight your contributions to previous projects and how they relate to the role.
Choose a category, try a prompt, then open its approach, worked solution or follow-up when you need it.
Explain how garbage collection works in Java.
Explain how garbage collection works in Java.
Approach
- Say what the runtime actually does before reasoning about the code.
- Name what is shared across threads and what owns each piece of state.
- Identify the window where an invariant is briefly untrue.
- 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?
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?
Implement a binary search algorithm in your preferred programming language.
Implement a binary search algorithm in your preferred programming language.
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?
How would you find the first non-repeating character in a string?
How would you find the first non-repeating character in a string?
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?
Write a program to sort an array using quicksort.
Write a program to sort an array using quicksort.
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?
How would you optimize a slow-running SQL query?
How would you optimize a slow-running SQL query?
Approach
- Name the grain you start from and join outward from it.
- Check whether any join is one-to-many before aggregating, or the sums inflate.
- Say which index the query would use, and what makes it unusable.
- Handle the rows that do not match: that is usually the actual question.
Follow-up
- How does the query change if that join becomes one-to-many?
- What happens to this when the table is ten times larger?
Write the update path that detects a concurrent edit
resource carries version INT NOT NULL DEFAULT 1. resource_revision holds revision_id, resource_id, version, actor_user_id, change_kind, patch JSONB, request_id, created_at with UNIQUE (resource_id, version). outbox_event holds aggregate_type, aggregate_id, aggregate_version, event_type, payload, status. A PUT carries the version the client read. Write the exact statements for the single transaction that applies the edit, records the revision and enqueues 'resource.updated', and give the handler's branch on zero affected rows. Then say what PostgreSQL 16 does under READ COMMITTED when two of these updates hit one row at once.
Approach
- One transaction, three writes, no network call inside it: UPDATE resource SET title = $3, version = version + 1, updated_at = now() WHERE resource_id = $1 AND tenant_id = $4 AND version = $2; then INSERT the resource_revision row at version $2 + 1; then INSERT the outbox_event row at the same aggregate_version. The event goes to a table rather than a broker because no transaction spans both.
- Branch on the affected-row count before doing anything else. Zero has three causes — stale version, wrong tenant, row gone — so re-read once and map to 409 carrying the current version, or 404 for an id outside the caller's tenant, which also stops the endpoint confirming that another tenant's id exists.
- State the engine behaviour instead of assuming it. Under READ COMMITTED the second UPDATE blocks on the row lock, and when the first commits PostgreSQL re-evaluates the WHERE clause against the newly committed row, so the version predicate now fails and the statement reports zero rows. Under REPEATABLE READ the identical collision raises SQLSTATE 40001 instead, so the handler must fold both shapes into one conflict response.
- Keep UNIQUE (resource_id, version) even though the predicate already serialises writers. It is what makes a lost update unwritable if any other path ever reaches the revision table, and it converts a logic bug into 23505 rather than into a silently missing history row.
Follow-up
- A client sends the version it read ten minutes ago and the resource has moved three versions. What is in your 409 so it can resolve the conflict without a full re-fetch?
- Two editors, two disjoint fields, no overlap. Does your answer still refuse the second write, and should it?
What are the key differences between object-oriented programming and functional programming?
What are the key differences between object-oriented programming and functional programming?
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?
Can you describe the SOLID principles of software development?
Can you describe the SOLID principles of software development?
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 is the difference between a stack and a queue?
What is the difference between a stack and a queue?
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?
Given a hypothetical scenario, how would you approach the design of a new feature?
Given a hypothetical scenario, how would you approach the design of a new feature?
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 handle a situation where a project is falling behind schedule?
How would you handle a situation where a project is falling behind schedule?
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 steps would you take to ensure code quality in a large codebase?
What steps would you take to ensure code quality in a large codebase?
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 approach learning a new programming language or framework?
How do you approach learning a new programming language or framework?
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 approach to debugging a complex application.
Describe your approach to debugging a complex application.
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 Air Apps candidates report.
Prepare, practise & reflect
One practical outcome each day. Spend longer where you need it.
0 / 7 done01Map the Air Apps loop
- Write out the reported sequence: Phone Screen, Technical Interviews, Behavioral Questions.
- 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 3 reported rounds, with the weakest marked.
02Work Programming (general problem solving)
- Spend the session on Programming (general problem solving), which Air Apps candidates report being tested on.
- Write one worked example in Programming (general problem solving) and time yourself on it.
Deliverable: One timed worked example in Programming (general problem solving).
03Work Object-Oriented Programming (OOP) principles
- Spend the session on Object-Oriented Programming (OOP) principles, which Air Apps candidates report being tested on.
- Write one worked example in Object-Oriented Programming (OOP) principles and time yourself on it.
Deliverable: One timed worked example in Object-Oriented Programming (OOP) principles.
04Work Java
- Spend the session on Java, which Air Apps candidates report being tested on.
- Write one worked example in Java and time yourself on it.
Deliverable: One timed worked example in Java.
05Answer out loud: Technical / Domain Questions
- Answer aloud, timed: What are the key differences between object-oriented programming and functional programming?
- Answer aloud, timed: Explain how garbage collection works in Java.
Deliverable: Spoken answers to 2 reported Technical / Domain Questions question(s), under time.
06Answer out loud: Coding / Algorithms
- Answer aloud, timed: Write a function to reverse a linked list.
- Answer aloud, timed: Implement a binary search algorithm in your preferred programming language.
Deliverable: Spoken answers to 2 reported Coding / Algorithms question(s), under time.
07Answer out loud: Behavioral / Leadership
- Answer aloud, timed: Describe a challenging project you worked on and how you overcame obstacles.
- Answer aloud, timed: How do you prioritize tasks when working on multiple projects?
Deliverable: Spoken answers to 2 reported Behavioral / Leadership 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.
Describe a challenging project you worked on and how you overcame obstacles.
Describe a challenging project you worked on and how you overcame obstacles.
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 working on multiple projects?
How do you prioritize tasks when working on multiple projects?
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?
Can you give an example of how you handled a conflict within a team?
Can you give an example of how you handled a conflict within a team?
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?
What motivates you to achieve your goals in a technical environment?
What motivates you to achieve your goals in a technical environment?
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 keep up with new technologies and industry trends?
How do you keep up with new technologies and industry trends?
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
Describe a challenging project you worked on and how you overcame obstacles.
- 02
How do you prioritize tasks when working on multiple projects?
- 03
Can you give an example of how you handled a conflict within a team?
- 04
What motivates you to achieve your goals in a technical environment?
How difficult are the interviews, and what preparation time is typical?
Interviews at Air Apps can vary in difficulty. Candidates typically spend several weeks preparing, focusing on technical skills and coding challenges. Familiarity with common algorithms and data structures is crucial.
Air Apps Software Engineer candidate reports ↗What differentiates successful candidates?
Successful candidates demonstrate not only technical proficiency but also strong problem-solving skills and a collaborative mindset. They align with Air Apps’ values and show a genuine interest in contributing to the team.
Air Apps Software Engineer candidate reports ↗What is the culture and working style at Air Apps?
Air Apps fosters a collaborative and innovative culture, where team members are encouraged to share ideas and learn from one another. Open communication and teamwork are key components of the work environment.
Air Apps Software Engineer candidate reports ↗What is the typical timeline from initial screen to offer?
The timeline can vary, but candidates often receive feedback within a few weeks after the initial interview stages. The entire process may take 4 to 6 weeks.
Air Apps Software Engineer candidate reports ↗Are there remote work opportunities?
Air Apps offers flexible work arrangements, including options for remote work, depending on the team's needs and project requirements.
Air Apps Software Engineer candidate reports ↗What topics does Air Apps test in interviews?
Air Apps interviews most often cover Java, Object-Oriented Programming (OOP), Programming (general problem solving), Coding Practice, and Quality Assurance (QA) Engineering. The exact emphasis depends on the specific role you apply for.
Air Apps 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.
- 01Air Apps 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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