As a Software Engineer at Favor, you play a pivotal role in shaping the technology that powers one of Texas's leading delivery services. This position is integral to ensuring that our platform operates seamlessly, providing users with a reliable and efficient experience. You'll be at the forefront of innovation, tackling complex challenges that enhance our product offerings and improve user satisfaction. Your work will involve collaborating closely with cross-functional teams, including product managers and designers, to deliver features that meet customer needs. Expect to engage with a diverse tech stack and be involved in projects that require creative problem-solving and an understanding of user-centric design. This role is not just about writing code; it’s about building solutions that resonate with our users and drive the business forward. At Favor, you'll have the opportunity to work on exciting initiatives, from optimizing our logistics algorithms to enhancing the user interface of our mobile application. The impact you make here is significant, as your contributions directly influence our ability to deliver exceptional service and expand our market presence.
Phone Screening
reportedInitial call to assess your background and fit for the role.
What to demonstrate
- Initial call to assess your background and fit for the role
- Depth in Coding Interviews
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
reportedIncludes coding challenges and system design questions to evaluate technical skills.
What to demonstrate
- Includes coding challenges and system design questions to evaluate technical skills
- Depth in Coding Interviews
How to prepare
- Answer aloud and timed: How do you ensure your CSS is maintainable and scalable?
- Answer aloud and timed: Describe a time when you optimized a piece of code. What approach did you take?
Onsite Interviews
reportedIn-depth interviews focusing on technical abilities and behavioral assessments.
What to demonstrate
- In-depth interviews focusing on technical abilities and behavioral assessments
- Depth in Coding Interviews
How to prepare
- Answer aloud and timed: What are the key differences between REST and GraphQL?
- Answer aloud and timed: Design a system for a real-time chat application. What considerations would you take into account?
PracHub editorial advice for the preparation topics above.
Be transparent
Clearly communicate your thought process during coding interviews. This helps interviewers understand your approach and reasoning.
Prepare for behavioral questions
Familiarize yourself with Favor's core values and be ready to discuss how they align with your experiences.
Practice coding challenges
Utilize platforms like LeetCode or HackerRank to sharpen your coding skills and improve your speed.
Ask insightful questions
Show your interest in the role and company by preparing thoughtful questions for your interviewers about team dynamics or upcoming projects.
Choose a category, try a prompt, then open its approach, worked solution or follow-up when you need it.
Explain the concept of closure in JavaScript. Can you provide an example?
Explain the concept of closure in JavaScript. Can you provide an example?
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?
Implement a function to merge two sorted arrays into one sorted array.
Implement a function to merge two sorted arrays into one sorted array.
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 given string is a palindrome.
Write a function to check if a given 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?
Describe an algorithm to find the longest substring without repeating characters.
Describe an algorithm to find the longest substring without repeating characters.
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 stack using queues?
How would you implement a stack using queues?
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 the "food rating" problem as described in Leetcode 2353.
Solve the "food rating" problem as described in Leetcode 2353.
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?
Explain why the owner filter ignores the listing index
The only index on resource is (tenant_id, status, updated_at DESC, resource_id DESC). A new endpoint returns one user's resources across all statuses, newest created first: WHERE tenant_id = $1 AND owner_user_id = $2 ORDER BY created_at DESC LIMIT 20. On a tenant with 2M rows it takes 900 ms and EXPLAIN shows a sort above a large scan. Explain precisely why the existing index cannot serve it, give the index that can, and state which of these the new index still will not help: owner_user_id alone across tenants; the same query ordered by updated_at. PostgreSQL 16.
Approach
- Separate the two jobs an index does. For filtering, a composite btree is seekable only on a left prefix, so with no predicate on status the scan can at best range over tenant_id and test owner_user_id per row; PostgreSQL 16 has no btree skip scan to jump the unconstrained column.
- For ordering, the index is sorted by (status, updated_at) within a tenant and not by created_at, so the LIMIT cannot stop early: every matching row is read and then sorted. That is the 'Sort Method: top-N heapsort' line, and it is why the plan reads 2M rows to answer with 20.
- Derive the replacement from the access path — equality, equality, then the ordering column: CREATE INDEX CONCURRENTLY ON resource (tenant_id, owner_user_id, created_at DESC). The scan seeks to the (tenant, owner) range and walks 20 entries in order, so the Sort node disappears along with the row-read.
- Treat INCLUDE (title, status) as conditional, not free. An index-only scan still visits the heap for any row whose page is not marked all-visible, so on a table taking 1.2k writes/second the win depends on autovacuum keeping the visibility map current, and the wider index costs more on every insert.
Follow-up
- 90% of rows are status='active'. Would a partial index WHERE status = 'active' change your answer, and for which of the three queries?
- A dashboard runs this for 40 owners in one page load. What changes about the design?
How do you ensure your CSS is maintainable and scalable?
How do you ensure your CSS is maintainable and scalable?
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 are the key differences between REST and GraphQL?
What are the key differences between REST and GraphQL?
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?
Design a system for a real-time chat application. What considerations would you take into account?
Design a system for a real-time chat application. What considerations would you take into account?
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 building a food rating system that allows users to leave reviews?
How would you approach building a food rating system that allows users to leave reviews?
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 how you would structure a database for a delivery service platform.
Discuss how you would structure a database for a delivery service platform.
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 are some challenges you anticipate when transitioning from a monolithic architecture to microservices?
What are some challenges you anticipate when transitioning from a monolithic architecture to microservices?
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 ensure data consistency in a distributed system?
How would you 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?
If a feature you've developed is not performing as expected, what steps would you take to investigate?
If a feature you've developed is not performing as expected, what steps would you take to investigate?
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 evaluate the effectiveness of a new feature after deployment?
How do you evaluate the effectiveness of a new feature after deployment?
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 metrics would you consider when assessing the performance of a delivery application?
What metrics would you consider when assessing the performance of a delivery 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?
Given a problem where users are not receiving notifications, how would you troubleshoot and identify the issue
Given a problem where users are not receiving notifications, how would you troubleshoot and identify the 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?
Describe how you would approach debugging a complex issue in production.
Describe how you would approach debugging a complex issue in production.
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 Favor candidates report.
Prepare, practise & reflect
One practical outcome each day. Spend longer where you need it.
0 / 7 done01Map the Favor loop
- Write out the reported sequence: Phone Screening, Technical Interview, Onsite 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 3 reported rounds, with the weakest marked.
02Work Coding Interviews
- Spend the session on Coding Interviews, which Favor candidates report being tested on.
- Write one worked example in Coding Interviews and time yourself on it.
Deliverable: One timed worked example in Coding Interviews.
03Work React
- Spend the session on React, which Favor candidates report being tested on.
- Write one worked example in React and time yourself on it.
Deliverable: One timed worked example in React.
04Work CSS
- Spend the session on CSS, which Favor candidates report being tested on.
- Write one worked example in CSS and time yourself on it.
Deliverable: One timed worked example in CSS.
05Answer out loud: Technical / Domain Questions
- Answer aloud, timed: What is your experience with React and how have you utilized it in previous projects?
- Answer aloud, timed: Explain the concept of closure in JavaScript. Can you provide an example?
Deliverable: Spoken answers to 2 reported Technical / Domain Questions question(s), under time.
06Answer out loud: System Design / Architecture
- Answer aloud, timed: Design a system for a real-time chat application. What considerations would you take into account?
- Answer aloud, timed: How would you approach building a food rating system that allows users to leave reviews?
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, and how did you handle obstacles?
- Answer aloud, timed: How do you prioritize tasks when faced with multiple deadlines?
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.
What is your experience with React and how have you utilized it in previous projects?
What is your experience with React and how have you utilized it in previous 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?
Describe a time when you optimized a piece of code. What approach did you take?
Describe a time when you optimized a piece of code. What approach did you take?
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, and how did you handle obstacles?
Describe a challenging project you worked on. What was your role, and how did you handle 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 faced with multiple deadlines?
How do you prioritize tasks when faced with multiple 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?
Can you provide an example of how you dealt with a conflict in a team setting?
Can you provide an example of how you dealt with a conflict in a team setting?
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 role as a software engineer?
What motivates you to succeed in your role as a software engineer?
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 ensure effective communication when working with cross-functional teams?
How do you ensure effective communication when working with cross-functional teams?
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
What is your experience with React and how have you utilized it in previous projects?
- 02
Describe a time when you optimized a piece of code. What approach did you take?
- 03
Describe a challenging project you worked on. What was your role, and how did you handle obstacles?
- 04
How do you prioritize tasks when faced with multiple deadlines?
How difficult are the interviews, and how much preparation time is typical?
The interviews at Favor can be challenging, especially the technical assessments. Candidates typically spend several weeks preparing, focusing on coding challenges and system design principles.
Favor Software Engineer candidate reports ↗What differentiates successful candidates?
Successful candidates often demonstrate a strong technical foundation, effective problem-solving skills, and the ability to communicate their thought process clearly.
Favor Software Engineer candidate reports ↗What is the culture and working style at Favor?
Favor fosters a collaborative and innovative environment. Teamwork and open communication are highly valued, and employees are encouraged to take initiative and contribute ideas.
Favor Software Engineer candidate reports ↗What is the typical timeline from initial screen to offer?
The entire process can take several weeks, with candidates usually receiving feedback within a week after each interview stage.
Favor Software Engineer candidate reports ↗Are there remote work or hybrid expectations?
While many roles may offer remote or hybrid options, it’s essential to clarify expectations during your initial interviews.
Favor Software Engineer candidate reports ↗What topics does Favor test in interviews?
Favor interviews most often cover Panel Interviewing, System Design, Behavioral Interviewing, Communication Skills, and SQL. The exact emphasis depends on the specific role you apply for.
Favor 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.
- 01Favor 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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