A Software Engineer at SmarterTravel plays a pivotal role in developing and maintaining the technology that powers travel planning and booking experiences for users worldwide. This position is critical as it directly impacts the quality, performance, and scalability of our products, which serve millions of travelers seeking the best travel deals and experiences. As part of a dynamic team, you will work on complex systems that integrate data from various sources to deliver seamless user experiences that enhance travel planning. In this role, you'll contribute to innovative projects that include building robust web applications, optimizing backend services, and implementing solutions that improve user engagement and satisfaction. Your work will not only influence the technical landscape of SmarterTravel but also shape the way users interact with travel services. Expect to engage with cross-functional teams, tackle challenging problems, and contribute to a culture of continuous improvement and innovation.
Phone Screening
reportedInitial phone screening to assess candidate's background and fit for the role.
What to demonstrate
- Initial phone screening to assess candidate's background and fit for the role
- Depth in System design
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
reportedOne or more technical interviews focused on assessing problem-solving abilities and technical knowledge.
What to demonstrate
- One or more technical interviews focused on assessing problem-solving abilities and technical knowledge
- Depth in System design
How to prepare
- Answer aloud and timed: Describe a time when you encountered a significant bug. How did you resolve it?
- Answer aloud and timed: How do you ensure code quality and maintainability in your projects?
Onsite Interview
reportedEngagement with potential team members and stakeholders during an onsite interview.
What to demonstrate
- Engagement with potential team members and stakeholders during an onsite interview
- Depth in System design
How to prepare
- Answer aloud and timed: Discuss your experience with version control systems, such as Git.
- Answer aloud and timed: Design a URL shortening service. What are the key components?
PracHub editorial advice for the preparation topics above.
Practice coding challenges
Regularly engage with coding platforms to enhance your problem-solving skills and speed.
Review system design principles
Familiarize yourself with common design patterns and architectures, as these will be crucial during technical interviews.
Prepare behavioral stories
Use the STAR method to structure your responses to behavioral questions, ensuring you provide clear and concise examples.
Align with company values
Research SmarterTravel's mission and values to articulate how your personal values align with the company's culture.
Choose a category, try a prompt, then open its approach, worked solution or follow-up when you need it.
Explain the difference between synchronous and asynchronous programming.
Explain the difference between synchronous and asynchronous programming.
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 string.
Write a function to reverse 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?
How would you implement a binary search algorithm?
How would you implement a binary search algorithm?
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?
Solve a problem involving sorting a list of integers.
Solve a problem involving sorting a list of integers.
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?
Discuss the time complexity of your solutions.
Discuss the time complexity of your solutions.
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 function to check if a string is a palindrome.
Write a function to check if a string is a palindrome.
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?
Denormalise tenant onto revisions and backfill it live
resource_revision (revision_id, resource_id, version, actor_user_id, change_kind, patch, request_id, created_at) has 400M rows and no tenant column; tenant_id lives only on resource. Two reads need it: a tenant-scoped audit feed ordered by created_at DESC, and an offboarding purge. Both join back to resource today. Justify adding tenant_id to resource_revision against those two reads, name the anomaly the copy introduces and the constraint that prevents it, then give the ordered migration for a live table taking 1.2k writes/second — the lock each step takes, how the backfill is batched, and where each step stops being reversible. PostgreSQL 16.
Approach
- Justify from the access path rather than from taste. Without the column, the audit feed either scans resource_revision by created_at and discards other tenants' rows, or resolves the tenant's resource_ids first and probes with them — both proportional to the tenant's whole history rather than to one page. With (tenant_id, created_at DESC, revision_id DESC) it is a seek that stops at 50 rows, and the purge becomes a ranged delete instead of a join.
- Name the cost exactly: a second copy of a fact can disagree with the first. Make the disagreement unwritable rather than documented — add UNIQUE (resource_id, tenant_id) on resource so it can serve as a foreign-key target, then FOREIGN KEY (resource_id, tenant_id) REFERENCES resource (resource_id, tenant_id) on the revision table. A revision can then only ever carry its parent's tenant.
- Step one, expand: ALTER TABLE resource_revision ADD COLUMN tenant_id BIGINT NULL, with no default, so it is a catalogue change and no rewrite. It still needs ACCESS EXCLUSIVE for an instant, and that instant queues behind the longest open transaction on the table while every later query queues behind it — set lock_timeout to 2s and retry rather than wait.
- Step two, dual-write: deploy the writer that populates tenant_id on every new revision while reads still use the join. Reversible by redeploying the previous build, because nothing reads the column yet.
Follow-up
- The backfill is half finished and a rollback is required. What state is the table in, and what does the previous build do with a half-populated column?
- How do you verify the backfill actually finished, given rows are still being inserted while it runs?
Find version gaps and relay lag with window functions
outbox_event holds event_id, aggregate_type, aggregate_id, aggregate_version, event_type, payload, status ('pending','published','dead'), attempts, created_at, published_at. A projection is missing rows and you must decide whether the relay skipped events or the consumer dropped them. Write three queries over the last seven days: one listing every aggregate_id whose published aggregate_version sequence has a hole, one giving per-day counts with a running total, and one returning the newest published event per aggregate. For each, say where the window function is evaluated relative to WHERE and LIMIT. PostgreSQL 16.
Approach
- Gaps: compute lead(aggregate_version) OVER (PARTITION BY aggregate_id ORDER BY aggregate_version) in a subquery, then filter next_version <> aggregate_version + 1 in the outer query. Window functions are evaluated after WHERE, GROUP BY and HAVING and before the outer ORDER BY and LIMIT, so the predicate cannot sit in the same WHERE clause and PostgreSQL 16 has no QUALIFY.
- Say what the seven-day filter does to the answer: it truncates every partition, so the first row per aggregate has no predecessor inside the window and a hole spanning the boundary is invisible. Widen the window, or join to resource.version as the authority for the true maximum.
- Running total: SELECT date_trunc('day', created_at) AS d, count() AS n, sum(count()) OVER (ORDER BY date_trunc('day', created_at) ROWS UNBOUNDED PRECEDING). An aggregate inside a window call is legal because grouping runs before windowing. The grouping key is unique per row here so ROWS and RANGE agree, but write the frame anyway — over ungrouped rows with tied timestamps the default RANGE frame pulls in every peer row and the total jumps.
- Newest per aggregate: DISTINCT ON (aggregate_id) ... ORDER BY aggregate_id, aggregate_version DESC is the cheap PostgreSQL-only form when an index matches that order; row_number() OVER (PARTITION BY aggregate_id ORDER BY aggregate_version DESC) = 1 is the portable form and needs a subquery for the same evaluation-order reason as the gap query.
Follow-up
- Relay failover redelivers events. Does a duplicate break the gap query, and how would you detect one from this table alone?
- Turn the gap check into a continuous monitor rather than a query someone runs after an incident. What does it watch?
What are the advantages of using RESTful APIs?
What are the advantages of using RESTful APIs?
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?
Design a URL shortening service. What are the key components?
Design a URL shortening service. What are the key components?
Approach
- Fix the scope first: who calls this, how often, and what they do when it fails.
- Name the read and write paths separately; they rarely have the same bottleneck.
- Choose a partition key and say what query it makes expensive.
- State the consistency you need, and where you are willing to be stale.
Follow-up
- What breaks first when traffic grows ten times?
- How does this behave when that dependency is down for an hour?
How would you approach designing a system to handle real-time flight data?
How would you approach designing a system to handle real-time flight data?
Approach
- Fix the scope first: who calls this, how often, and what they do when it fails.
- Name the read and write paths separately; they rarely have the same bottleneck.
- Choose a partition key and say what query it makes expensive.
- State the consistency you need, and where you are willing to be stale.
Follow-up
- What breaks first when traffic grows ten times?
- How does this behave when that dependency is down for an hour?
Explain how you would ensure data consistency in a distributed system.
Explain how you would ensure data consistency in a distributed system.
Approach
- Fix the scope first: who calls this, how often, and what they do when it fails.
- Name the read and write paths separately; they rarely have the same bottleneck.
- Choose a partition key and say what query it makes expensive.
- State the consistency you need, and where you are willing to be stale.
Follow-up
- What breaks first when traffic grows ten times?
- How does this behave when that dependency is down for an hour?
What considerations would you take into account when designing a microservices architecture?
What considerations would you take into account when designing a microservices architecture?
Approach
- Fix the scope first: who calls this, how often, and what they do when it fails.
- Name the read and write paths separately; they rarely have the same bottleneck.
- Choose a partition key and say what query it makes expensive.
- State the consistency you need, and where you are willing to be stale.
Follow-up
- What breaks first when traffic grows ten times?
- How does this behave when that dependency is down for an hour?
Describe how you would optimize a slow-performing application.
Describe how you would optimize a slow-performing application.
Approach
- Fix the scope first: who calls this, how often, and what they do when it fails.
- Name the read and write paths separately; they rarely have the same bottleneck.
- Choose a partition key and say what query it makes expensive.
- State the consistency you need, and where you are willing to be stale.
Follow-up
- What breaks first when traffic grows ten times?
- How does this behave when that dependency is down for an hour?
If a client requests a feature that you believe is unnecessary, how would you address this?
If a client requests a feature that you believe is unnecessary, how would you address this?
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 how you would approach a situation where you have incomplete requirements.
Describe how you would approach a situation where you have incomplete requirements.
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 gather user feedback on a new feature?
What steps would you take to gather user feedback on 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 do you define success for a project?
How do you define success for a project?
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 troubleshoot a performance issue in a live application?
How would you troubleshoot a performance issue in a live 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 SmarterTravel candidates report.
Prepare, practise & reflect
One practical outcome each day. Spend longer where you need it.
0 / 7 done01Map the SmarterTravel loop
- Write out the reported sequence: Phone Screening, Technical Interviews, Onsite Interview.
- 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 System design
- Spend the session on System design, which SmarterTravel candidates report being tested on.
- Write one worked example in System design and time yourself on it.
Deliverable: One timed worked example in System design.
03Work Modern web fundamentals
- Spend the session on Modern web fundamentals, which SmarterTravel candidates report being tested on.
- Write one worked example in Modern web fundamentals and time yourself on it.
Deliverable: One timed worked example in Modern web fundamentals.
04Work Phone coding interviews
- Spend the session on Phone coding interviews, which SmarterTravel candidates report being tested on.
- Write one worked example in Phone coding interviews and time yourself on it.
Deliverable: One timed worked example in Phone coding interviews.
05Answer out loud: Technical / Domain Questions
- Answer aloud, timed: Explain the difference between synchronous and asynchronous programming.
- Answer aloud, timed: What are the advantages of using RESTful APIs?
Deliverable: Spoken answers to 2 reported Technical / Domain Questions question(s), under time.
06Answer out loud: System Design / Architecture
- Answer aloud, timed: Design a URL shortening service. What are the key components?
- Answer aloud, timed: How would you approach designing a system to handle real-time flight data?
Deliverable: Spoken answers to 2 reported System Design / Architecture question(s), under time.
07Answer out loud: Behavioral / Leadership
- Answer aloud, timed: Describe a challenging project you worked on. What was your role?
- Answer aloud, timed: How do you handle disagreements with team members?
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 time when you encountered a significant bug. How did you resolve it?
Describe a time when you encountered a significant bug. How did you resolve 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?
Discuss your experience with version control systems, such as Git.
Discuss your experience with version control systems, such as Git.
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 challenging project you worked on. What was your role?
Describe a challenging project you worked on. What was your role?
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 disagreements with team members?
How do you handle disagreements with team members?
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 led a project or initiative.
Give an example of how you led a project or initiative.
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 excel in your work?
What motivates you to excel in your work?
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?
- 01
Describe a time when you encountered a significant bug. How did you resolve it?
- 02
Discuss your experience with version control systems, such as Git.
- 03
Describe a challenging project you worked on. What was your role?
- 04
How do you handle disagreements with team members?
How difficult is the interview process, and how much preparation time is typical?
The interview process for the Software Engineer position at SmarterTravel can be challenging, requiring a solid understanding of technical concepts and problem-solving skills. Candidates typically spend several weeks preparing, focusing on coding exercises and system design principles.
SmarterTravel Software Engineer candidate reports ↗What differentiates successful candidates?
Successful candidates tend to demonstrate a strong technical foundation, an ability to communicate effectively, and an alignment with SmarterTravel's values. They often exhibit curiosity and a willingness to learn, which are highly valued in our collaborative environment.
SmarterTravel Software Engineer candidate reports ↗What is the culture and working style at SmarterTravel?
SmarterTravel promotes a culture of collaboration, innovation, and continuous learning. Engineers are encouraged to share ideas, take initiative, and contribute to a supportive team environment. Flexibility and adaptability are also essential traits in our fast-paced industry.
SmarterTravel Software Engineer candidate reports ↗What is the typical timeline from the initial screen to an offer?
The timeline can vary, but candidates can generally expect the process to take 3-4 weeks from the initial phone screen to receiving an offer. Timely communication and feedback are important aspects of our process.
SmarterTravel Software Engineer candidate reports ↗Are there remote work or hybrid expectations?
While SmarterTravel embraces flexible work arrangements, specific expectations may vary by team and project. It is advisable to discuss your preferences during the initial stages of the interview process.
SmarterTravel Software Engineer candidate reports ↗What topics does SmarterTravel test in interviews?
SmarterTravel interviews most often cover Business Analysis, Account Executive (Sales) Role Fundamentals, System design, Project-based interviewing (resume-driven technical discussion), and Project Documentation & Storytelling. The exact emphasis depends on the specific role you apply for.
SmarterTravel 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.
- 01SmarterTravel 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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