As a Software Engineer at Quest Analytics, you play a vital role in shaping the technological backbone of the organization. Your engineering expertise contributes directly to the development of innovative software solutions that enhance data analytics for healthcare providers and payers. In this position, you will be part of a dynamic team that leverages cutting-edge technologies to create products that improve healthcare outcomes and streamline operations. You will be responsible for designing, developing, testing, and maintaining scalable software applications that support Quest Analytics' mission of empowering healthcare decision-making through data. The complexity and scale of the systems you will work on are significant; they impact not only the company's operations but also the broader healthcare ecosystem. Your contributions will help drive strategic initiatives and ensure that our products meet the needs of our users, making this role both challenging and rewarding.
Phone Screen
reportedInitial call conducted by a recruiter to gauge your background and interest in the role.
What to demonstrate
- Initial call conducted by a recruiter to gauge your background and interest in the role
- Depth in Software Engineering (Core)
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
reportedIn-depth technical interview with the hiring manager and possibly a lead engineer.
What to demonstrate
- In-depth technical interview with the hiring manager and possibly a lead engineer
- Depth in Software Engineering (Core)
How to prepare
- Answer aloud and timed: How do you ensure code quality and maintainability in your work?
- Answer aloud and timed: Can you explain a complex technical problem you solved and the approach you took?
Final Interview
reportedInterview with higher management, such as the VP or CTO, combining conversational and technical elements.
What to demonstrate
- Interview with higher management, such as the VP or CTO, combining conversational and technical elements
- Depth in Software Engineering (Core)
How to prepare
- Answer aloud and timed: What strategies do you use for debugging and troubleshooting software issues?
- Answer aloud and timed: How would you approach optimizing a slow-running application?
PracHub editorial advice for the preparation topics above.
Practice coding challenges
Regularly solve coding problems on platforms like LeetCode or HackerRank to sharpen your skills and gain confidence.
Prepare for behavioral questions
Use the STAR method (Situation, Task, Action, Result) to structure your responses and highlight relevant experiences.
Research the company
Familiarize yourself with Quest Analytics' products and mission to articulate how your skills align with the company's goals.
Engage with your interviewer
Treat interviews as a two-way conversation. Ask insightful questions about the team dynamics and company culture to demonstrate your interest.
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?
How would you implement a binary search algorithm? Explain its time complexity.
How would you implement a binary search algorithm? Explain its time complexity.
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 algorithms and discuss their efficiency.
Solve a problem involving sorting algorithms and discuss their efficiency.
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?
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?
What programming languages are you proficient in, and how have you used them in past projects?
What programming languages are you proficient in, and how have you used them in past 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 do you ensure code quality and maintainability in your work?
How do you ensure code quality and maintainability in your 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?
Can you explain a complex technical problem you solved and the approach you took?
Can you explain a complex technical problem you solved and the approach you took?
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 optimizing a slow-running application?
How would you approach optimizing a slow-running application?
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 a situation where you had to balance competing priorities. How did you manage it?
Describe a situation where you had to balance competing priorities. How did you manage 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?
If faced with a tight deadline, how would you prioritize tasks to ensure project completion?
If faced with a tight deadline, how would you prioritize tasks to ensure project completion?
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 system for managing user data while ensuring security and privacy.
Design a system for managing user data while ensuring security and privacy.
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 structure a microservices architecture for a new application?
How would you structure a microservices architecture for a new 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?
Discuss the trade-offs between monolithic and microservices architectures.
Discuss the trade-offs between monolithic and microservices architectures.
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 strategies do you use for debugging and troubleshooting software issues?
What strategies do you use for debugging and troubleshooting software issues?
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 Quest Analytics candidates report.
Prepare, practise & reflect
One practical outcome each day. Spend longer where you need it.
0 / 7 done01Map the Quest Analytics loop
- Write out the reported sequence: Phone Screen, Technical Interview, Final 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 Software Engineering (Core)
- Spend the session on Software Engineering (Core), which Quest Analytics candidates report being tested on.
- Write one worked example in Software Engineering (Core) and time yourself on it.
Deliverable: One timed worked example in Software Engineering (Core).
03Work Software Architecture
- Spend the session on Software Architecture, which Quest Analytics candidates report being tested on.
- Write one worked example in Software Architecture and time yourself on it.
Deliverable: One timed worked example in Software Architecture.
04Work Technical Interviewing (Coding/Problem Solving)
- Spend the session on Technical Interviewing (Coding/Problem Solving), which Quest Analytics candidates report being tested on.
- Write one worked example in Technical Interviewing (Coding/Problem Solving) and time yourself on it.
Deliverable: One timed worked example in Technical Interviewing (Coding/Problem Solving).
05Answer out loud: Technical / Domain Questions
- Answer aloud, timed: What programming languages are you proficient in, and how have you used them in past projects?
- Answer aloud, timed: Describe your experience with RESTful API design and implementation.
Deliverable: Spoken answers to 2 reported Technical / Domain Questions question(s), under time.
06Answer out loud: Problem-Solving / Case Studies
- Answer aloud, timed: How would you approach optimizing a slow-running application?
- Answer aloud, timed: Describe a situation where you had to balance competing priorities. How did you manage it?
Deliverable: Spoken answers to 2 reported Problem-Solving / Case Studies question(s), under time.
07Answer out loud: Behavioral / Leadership Questions
- Answer aloud, timed: Tell me about a time you had a conflict with a colleague. How did you resolve it?
- Answer aloud, timed: How do you handle feedback about your work? Can you provide an example?
Deliverable: Spoken answers to 2 reported Behavioral / Leadership Questions 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 your experience with RESTful API design and implementation.
Describe your experience with RESTful API design and implementation.
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 a conflict with a colleague. How did you resolve it?
Tell me about a time you had a conflict with a colleague. 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?
How do you handle feedback about your work? Can you provide an example?
How do you handle feedback about your work? Can you provide an example?
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 how you have influenced a team or project in your previous roles.
Describe how you have influenced a team or project in your previous roles.
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 your experience with RESTful API design and implementation.
- 02
Tell me about a time you had a conflict with a colleague. How did you resolve it?
- 03
How do you handle feedback about your work? Can you provide an example?
- 04
Describe how you have influenced a team or project in your previous roles.
What is the typical interview difficulty, and how much preparation time is recommended?
The interview process is generally considered average in difficulty. Candidates should allocate several weeks for preparation, focusing on the key areas outlined in this guide.
Quest Analytics Software Engineer candidate reports ↗What differentiates successful candidates at Quest Analytics?
Successful candidates tend to demonstrate a strong technical foundation, effective problem-solving skills, and a collaborative mindset that aligns with the company’s values.
Quest Analytics Software Engineer candidate reports ↗Can you describe the culture and working style at Quest Analytics?
The culture at Quest Analytics emphasizes teamwork, innovation, and a commitment to improving healthcare through technology. Collaboration is encouraged across all levels of the organization.
Quest Analytics Software Engineer candidate reports ↗What is the typical timeline from the initial screen to an offer?
The timeline can vary, but candidates can expect the entire process to take anywhere from two to four weeks, depending on the availability of interviewers and candidates.
Quest Analytics Software Engineer candidate reports ↗Are there remote work opportunities or hybrid expectations?
Quest Analytics offers remote work options for certain positions, allowing for flexible work arrangements while maintaining strong team collaboration.
Quest Analytics Software Engineer candidate reports ↗What topics does Quest Analytics test in interviews?
Quest Analytics interviews most often cover Behavioral Interviewing, Problem Solving, Requirements Clarification, Account Executive (AE) Sales, and Software Engineering (Core). The exact emphasis depends on the specific role you apply for.
Quest Analytics 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.
- 01Quest Analytics 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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