As a Software Engineer at KLAS Research, you play a vital role in shaping the healthcare landscape through innovative software solutions. The position is not merely about writing code; it encompasses a critical responsibility for developing systems that enhance the efficiency and effectiveness of healthcare providers. Your contributions help create products that empower users to make informed decisions, ultimately impacting patient care and operational processes across the industry. This role demands a blend of technical acumen and a user-centric mindset, as you will be involved in designing, building, and maintaining software that serves a wide array of stakeholders. You will collaborate closely with cross-functional teams, including product managers and data analysts, to tackle complex challenges that require innovative thinking and a deep understanding of healthcare technology. The scale and complexity of KLAS Research’s projects offer a unique opportunity for growth and influence within a meaningful domain.
Phone Screen
reportedInitial discussion to review your background and gauge mutual interest.
What to demonstrate
- Initial discussion to review your background and gauge mutual interest
- Depth in Coding interviews (general)
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
reportedIn-depth interviews that may include coding challenges, system design discussions, and behavioral questions.
What to demonstrate
- In-depth interviews that may include coding challenges, system design discussions, and behavioral questions
- Depth in Coding interviews (general)
How to prepare
- Answer aloud and timed: Can you describe how you would optimize a slow-running SQL query?
- Answer aloud and timed: What are the principles of Object-Oriented Programming?
PracHub editorial advice for the preparation topics above.
Research the Company
Understanding KLAS Research’s mission and values will help you align your answers with their expectations during interviews.
Practice Coding
Be prepared to solve coding challenges on a whiteboard or coding platform. Regular practice is essential for success.
Prepare Questions
Have insightful questions ready for your interviewers. This shows your interest in the role and the organization.
Showcase Your Work
Be ready to discuss past projects and how they relate to the position you are applying for.
Choose a category, try a prompt, then open its approach, worked solution or follow-up when you need it.
How do you manage memory in your applications?
How do you manage memory in your applications?
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?
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?
Given an array of integers, find two numbers that add up to a specific target.
Given an array of integers, find two numbers that add 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?
Can you explain the time complexity of your solution?
Can you 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?
Can you describe how you would optimize a slow-running SQL query?
Can you describe how you would 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?
Replace offset paging on the resource feed with keyset
resource holds resource_id, tenant_id, owner_user_id, title, body_ref, version, status ('draft','active','archived','deleted'), created_at, updated_at, deleted_at, with an index on (tenant_id, status, updated_at DESC, resource_id DESC). The listing endpoint returns active resources for one tenant, newest update first, 50 per page, today with LIMIT 50 OFFSET n. Tenants reach page 400 and rows are created while they read. Write the keyset query, define what the cursor carries and how it is encoded, and say which part of the index each predicate uses. Assume PostgreSQL 16.
Approach
- Name the two failures separately. OFFSET 20000 makes the server produce and discard 20,000 rows, so page cost grows with depth rather than with page size. Independently, any write that changes how many rows sort above the offset moves the window between two fetches, and the direction decides which anomaly you get: an insert lands at the head of updated_at DESC and pushes already-returned rows down past the boundary, so they are returned a second time; a delete above the offset, or a row whose updated_at is bumped above the cursor, pulls rows up and one is never returned at all. Nothing in the response reveals either.
- Write the seek: WHERE tenant_id = $1 AND status = 'active' AND (updated_at, resource_id) < ($2, $3) ORDER BY updated_at DESC, resource_id DESC LIMIT 50. The row-value comparison is one index range rather than a disjunction, and both columns are NOT NULL, which is what makes that comparison well defined.
- Map each predicate onto the index: tenant_id and status are equality on the leading columns, (updated_at, resource_id) is the range, and the ORDER BY matches the index order so no Sort node appears and the scan stops after 50 rows. The DESC in the definition only matters for mixed directions — a plain ascending btree on the same columns is read backwards for this query.
- Put both sort columns in the cursor and nothing the client can tamper with into another tenant: base64 of (updated_at, resource_id), validated server-side, with tenant_id taken from the principal.
Follow-up
- The client asks for 'jump to page 400'. What do you offer instead, and what does the honest version cost?
- Sort order becomes user-selectable across four columns. How many indexes is that, and which would you refuse to add?
Explain the differences between REST and SOAP.
Explain the differences between REST and SOAP.
Approach
- Say who the caller is and what they do when the call fails halfway.
- Define the identity of a request so a retry cannot double-apply it.
- Separate accepted, pending, failed and confirmed; they are different facts.
- Design the error taxonomy before the success shape; callers branch on it.
Follow-up
- What happens if the caller retries after a timeout?
- How does a client discover it is on an old version of this contract?
What are the principles of Object-Oriented Programming?
What are the principles of Object-Oriented 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?
Describe a challenging bug you encountered and how you resolved it.
Describe a challenging bug you encountered 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?
How would you design a system to track patient data securely?
How would you design a system to track patient data securely?
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?
Given a set of requirements, how would you determine the best architecture for a new application?
Given a set of requirements, how would you determine the best 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?
If you were faced with a tight deadline, how would you ensure quality work?
If you were faced with a tight deadline, how would you ensure quality 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?
Walk me through your thought process for debugging a software issue.
Walk me through your thought process for debugging a software issue.
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 KLAS Research candidates report.
Prepare, practise & reflect
One practical outcome each day. Spend longer where you need it.
0 / 7 done01Map the KLAS Research loop
- Write out the reported sequence: Phone Screen, Technical Interviews.
- 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 2 reported rounds, with the weakest marked.
02Work Coding interviews (general)
- Spend the session on Coding interviews (general), which KLAS Research candidates report being tested on.
- Write one worked example in Coding interviews (general) and time yourself on it.
Deliverable: One timed worked example in Coding interviews (general).
03Work Problem-solving (coding)
- Spend the session on Problem-solving (coding), which KLAS Research candidates report being tested on.
- Write one worked example in Problem-solving (coding) and time yourself on it.
Deliverable: One timed worked example in Problem-solving (coding).
04Work Phone screening
- Spend the session on Phone screening, which KLAS Research candidates report being tested on.
- Write one worked example in Phone screening and time yourself on it.
Deliverable: One timed worked example in Phone screening.
05Answer out loud: Technical / Domain Questions
- Answer aloud, timed: Explain the differences between REST and SOAP.
- Answer aloud, timed: How do you manage memory in your applications?
Deliverable: Spoken answers to 2 reported Technical / Domain Questions question(s), under time.
06Answer out loud: Behavioral / Leadership Questions
- Answer aloud, timed: Tell me about a time you had a conflict with a team member. How did you handle it?
- Answer aloud, timed: Describe a project where you took the lead. What was the outcome?
Deliverable: Spoken answers to 2 reported Behavioral / Leadership Questions question(s), under time.
07Answer out loud: Problem-Solving / Case Studies
- Answer aloud, timed: How would you design a system to track patient data securely?
- Answer aloud, timed: Given a set of requirements, how would you determine the best architecture for a new application?
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.
Tell me about a time you had a conflict with a team member. How did you handle it?
Tell me about a time you had a conflict with a 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 project where you took the lead. What was the outcome?
Describe a project where you took the lead. What was the outcome?
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?
What motivates you to succeed in your work?
What motivates you to succeed 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?
Explain how you handle feedback or criticism.
Explain how you handle feedback or criticism.
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
Tell me about a time you had a conflict with a team member. How did you handle it?
- 02
Describe a project where you took the lead. What was the outcome?
- 03
How do you prioritize tasks when working on multiple projects?
- 04
What motivates you to succeed in your work?
How difficult are the interviews at KLAS Research?
The interviews are moderately challenging, focusing on both technical skills and cultural fit. Candidates should prepare thoroughly, especially in areas relevant to the role.
KLAS Research Software Engineer candidate reports ↗What differentiates successful candidates?
Successful candidates demonstrate a strong technical foundation, effective communication skills, and an alignment with the company’s values.
KLAS Research Software Engineer candidate reports ↗What is the typical timeline from initial screen to offer?
The timeline can vary, but candidates typically receive feedback within a few weeks after their final interview.
KLAS Research Software Engineer candidate reports ↗How does the company support remote work?
KLAS Research offers flexible working arrangements, including remote work options, depending on team needs and project requirements.
KLAS Research Software Engineer candidate reports ↗What is the company culture like?
The culture at KLAS Research emphasizes collaboration, innovation, and a strong commitment to improving healthcare outcomes through technology.
KLAS Research Software Engineer candidate reports ↗What topics does KLAS Research test in interviews?
KLAS Research interviews most often cover Presentation Skills, Stakeholder Communication, Time Management, UX/UI Design, and Business Analysis. The exact emphasis depends on the specific role you apply for.
KLAS Research 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.
- 01KLAS Research 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