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Neighbor Software Engineer Interview Guide

Neighbor Software Engineer interview guide: reported rounds, questions and how candidates describe the process.

The 60-second brief

As a Software Engineer at Neighbor, you are responsible for building and scaling the "Airbnb of storage"—a peer-to-peer marketplace that connects people with unused space to those in need of storage. This role is central to Neighbor’s mission of providing affordable, hyper-local storage solutions while enabling hosts to earn passive income. Your work directly impacts the core marketplace mechanics, including search and matching algorithms, trust and safety infrastructure, payment processing, and localized map interfaces. The engineering team at Neighbor operates in a fast-paced, high-ownership startup environment. Because the platform relies heavily on trust, seamless user experiences, and real-time transaction processing, engineers must balance rapid feature delivery with robust, high-quality code.

This guide is scoped to a Software Engineer candidate at Neighbor.

Focus areas

  • Behavioral Interviewing
  • Coding Challenges (Timed)
  • Interview Process Design (Multi-round Interviews)

The Neighbor interview process

Neighbor candidates report 4 rounds over 3-5 weeks. The stages below are what candidates describe, not a published process.

Recruiter Call

Initial conversation focused on your background and interest in Neighbor.

What to demonstrate

  • Initial conversation focused on your background and interest in Neighbor
  • Depth in Behavioral Interviewing

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 Screening

Complete a timed online coding challenge or a take-home technical project.

What to demonstrate

  • Complete a timed online coding challenge or a take-home technical project
  • Depth in Behavioral Interviewing

How to prepare

  • Answer aloud and timed: Given an array of booking intervals, determine if there are any overlapping schedules for a specific storage space.
  • Answer aloud and timed: Optimize a search query algorithm to rank listings based on distance, price, and host responsiveness.

Comprehensive Interview Round

Deep dives into coding, system architecture, and behavioral interviews with team members.

What to demonstrate

  • Deep dives into coding, system architecture, and behavioral interviews with team members
  • Depth in Behavioral Interviewing

How to prepare

  • Answer aloud and timed: How would you design a real-time messaging system between hosts and renters that ensures privacy and safety?
  • Answer aloud and timed: Design a scalable payment and payout system that handles security deposits, monthly recurring billing, and host disbursements.

CEO Interview

Final behavioral interview focusing on career alignment and commitment to company growth.

What to demonstrate

  • Final behavioral interview focusing on career alignment and commitment to company growth
  • Depth in Behavioral Interviewing

How to prepare

  • Answer aloud and timed: How would you architect a geospatial search service to handle rapid queries for listings within a highly populated metropolitan area?
  • Answer aloud and timed: Describe how you would handle race conditions when two renters attempt to book the same storage space simultaneously.

Where candidates lose points

Do your homework on the marketplace model

Be ready to discuss the unique challenges of peer-to-peer platforms, such as managing supply and demand, building trust, and optimizing local search.

Showcase your drive and passion

During your conversations, explicitly highlight your motivation, your work ethic, and your excitement about building a major tech company based in Utah.

Be transparent about your expectations

Since Neighbor emphasizes an in-office culture and a high-commitment work style, ensure these expectations align with your personal career goals before moving deep into the process.

Prepare structured behavioral examples

Use the STAR method (Situation, Task, Action, Result) to describe how you have successfully navigated tight deadlines, technical debt, and team collaboration in past roles.

Questions & practice

Implement a function to find the shortest path between host locations and a renter's search coordinate within

Medium · Coding & Algorithmic Problem Solving

Implement a function to find the shortest path between host locations and a renter's search coordinate within a specific radius.

Approach

  1. Restate the input: its shape, its size, and what is guaranteed about it.
  2. Name the brute-force solution and its complexity before improving on it.
  3. Choose the data structure from the access pattern, not from familiarity.
  4. 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 booking intervals, determine if there are any overlapping schedules for a specific storage s

Medium · Coding & Algorithmic Problem Solving

Given an array of booking intervals, determine if there are any overlapping schedules for a specific storage space.

Approach

  1. Restate the input: its shape, its size, and what is guaranteed about it.
  2. Name the brute-force solution and its complexity before improving on it.
  3. Choose the data structure from the access pattern, not from familiarity.
  4. 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 how you would handle race conditions when two renters attempt to book the same storage space simultan

Medium · System Design & Marketplace Architecture

Describe how you would handle race conditions when two renters attempt to book the same storage space simultaneously.

Approach

  1. Say what the runtime actually does before reasoning about the code.
  2. Name what is shared across threads and what owns each piece of state.
  3. Identify the window where an invariant is briefly untrue.
  4. 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?

Optimize a search query algorithm to rank listings based on distance, price, and host responsiveness.

Medium · Coding & Algorithmic Problem Solving

Approach

  1. Name the grain you start from and join outward from it.
  2. Check whether any join is one-to-many before aggregating, or the sums inflate.
  3. Say which index the query would use, and what makes it unusable.
  4. 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?

Stop tag and share joins from fanning out a page

Medium · join fan-out · semi-joins · many-to-many

resource_tag is (resource_id, tag_id) with PK (resource_id, tag_id); resource_share is (resource_id, shared_with_user_id, permission). The tagged-and-shared listing inner-joins resource to both, filters tenant_id, tag_id = ANY($2) and shared_with_user_id = $3, orders by updated_at DESC and takes 50. Pages come back with fewer than 50 distinct resources and the total in the header is far too high. Explain the row multiplication, rewrite both the page query and the count query so each is correct, and name the index each one needs. PostgreSQL 16.

Approach

  1. Do the arithmetic against the predicates that are actually there. An inner join emits one row per matching child row, and both joins are filtered: tag_id = ANY($2) admits only the requested tags, shared_with_user_id = $3 admits one user's share rows. So a resource holding three of the requested tags and shared with $3 once yields three rows, not one — the multiplier is its count of matching tags times its share rows for that single user, and that second factor is 1 unless the table admits duplicate (resource_id, shared_with_user_id) pairs. LIMIT 50 then limits rows rather than resources, and COUNT(*) counts pairs — the header is the product, not the population.
  2. Reject DISTINCT as the fix. It deduplicates after the product has been built, so the planner must materialise and sort the fanned-out set before the LIMIT can apply, and it leaves any SUM or AVG in the same select list wrong.
  3. Rewrite both filters as semi-joins, keeping resource as the only row source: AND EXISTS (SELECT 1 FROM resource_tag rt WHERE rt.resource_id = r.resource_id AND rt.tag_id = ANY($2)) and the same shape against resource_share. A semi-join stops at the first match per resource and preserves the driving index order, so ORDER BY updated_at DESC, resource_id DESC LIMIT 50 still stops after 50 rows.
  4. Count with the same predicates and no join at all: SELECT count(*) FROM resource r WHERE r.tenant_id = $1 AND r.status = 'active' AND EXISTS (...) AND EXISTS (...). Nothing multiplies a resource, so the number is the population.

Follow-up

  • The filter changes from 'any of these tags' to 'all of these tags'. Rewrite it and state what it costs relative to the ANY form.
  • A resource can be shared with the same user twice under different permissions. Does your count change, and should it?

Design an algorithm to detect duplicate listings or fraudulent host accounts based on shared metadata.

Medium · Coding & Algorithmic Problem Solving

Approach

  1. Fix the scope first: who calls this, how often, and what they do when it fails.
  2. Name the read and write paths separately; they rarely have the same bottleneck.
  3. Choose a partition key and say what query it makes expensive.
  4. 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 design a real-time messaging system between hosts and renters that ensures privacy and safety?

Medium · System Design & Marketplace Architecture

Approach

  1. Fix the scope first: who calls this, how often, and what they do when it fails.
  2. Name the read and write paths separately; they rarely have the same bottleneck.
  3. Choose a partition key and say what query it makes expensive.
  4. 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?

Design a scalable payment and payout system that handles security deposits, monthly recurring billing, and hos

Medium · System Design & Marketplace Architecture

Design a scalable payment and payout system that handles security deposits, monthly recurring billing, and host disbursements.

Approach

  1. Fix the scope first: who calls this, how often, and what they do when it fails.
  2. Name the read and write paths separately; they rarely have the same bottleneck.
  3. Choose a partition key and say what query it makes expensive.
  4. 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 architect a geospatial search service to handle rapid queries for listings within a highly popul

Medium · System Design & Marketplace Architecture

How would you architect a geospatial search service to handle rapid queries for listings within a highly populated metropolitan area?

Approach

  1. Fix the scope first: who calls this, how often, and what they do when it fails.
  2. Name the read and write paths separately; they rarely have the same bottleneck.
  3. Choose a partition key and say what query it makes expensive.
  4. 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?

Every query on one table stalls for forty seconds mid-deploy

Medium · lock contention · ddl · migrations

During a release on PostgreSQL, every query touching resource times out for about 40 seconds and then recovers with no intervention. The release ran one migration, ALTER TABLE resource ADD COLUMN archived_reason TEXT, and the migration log shows it completing in 6 ms. Unrelated tables showed no change in error rate. Explain how a 6 ms statement caused a 40-second stall, give the ordered checks you would run on a live system to confirm it, and give the migration procedure that prevents a repeat.

Approach

  1. Separate the statement's duration from the lock's duration. ADD COLUMN with no default is a catalogue-only change and genuinely runs in milliseconds, but it requires ACCESS EXCLUSIVE, and it cannot acquire that until every transaction already touching the table has finished.
  2. Account for the queueing, which is the part that surprises people. A lock request that is waiting blocks later requests for conflicting modes behind it rather than letting them overtake, so one long-open transaction holds the DDL and the DDL holds all the traffic. The stall length is set by the longest open transaction, not by the size of the change.
  3. Confirm on a live system in this order: pg_stat_activity for that table ordered by xact_start, looking for the oldest transaction and specifically for state = idle in transaction; then pg_locks where granted = false to find the waiter; then join them on pid to name blocker and blocked. pg_blocking_pids() does that join for you and is the fastest single call.
  4. Prevent rather than merely time it better. Set lock_timeout to a second or two on the migration session so the DDL abandons the queue after a bounded wait and is retried, instead of holding it for as long as the oldest transaction lives. Be exact about what that buys: queries arriving during the wait still queue behind the pending ACCESS EXCLUSIVE request, so each attempt costs them up to one lock_timeout of added latency. The outage goes from 40 seconds to about one second per attempt, not to zero. Also run migrations away from deploy-time peaks, and put a statement timeout and an idle-in-transaction timeout on the analytics role that opens the long transactions.

Follow-up

  • The same release also wants NOT NULL on that column. What is the sequence that gets there without a long lock?
  • Your lock_timeout retry fails ten times in a row because the analytics transaction is always open. What do you change?

Suggested practice checklist

Built from the rounds and topics Neighbor candidates report.

Day 1 — Map the Neighbor loop

  • Write out the reported sequence: Recruiter Call, Technical Screening, Comprehensive Interview Round, CEO 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 4 reported rounds, with the weakest marked.

Day 2 — Work Behavioral Interviewing

  • Spend the session on Behavioral Interviewing, which Neighbor candidates report being tested on.
  • Write one worked example in Behavioral Interviewing and time yourself on it.

Deliverable: One timed worked example in Behavioral Interviewing.

Day 3 — Work Coding Challenges (Timed)

  • Spend the session on Coding Challenges (Timed), which Neighbor candidates report being tested on.
  • Write one worked example in Coding Challenges (Timed) and time yourself on it.

Deliverable: One timed worked example in Coding Challenges (Timed).

Day 4 — Work Interview Process Design (Multi-round Interviews)

  • Spend the session on Interview Process Design (Multi-round Interviews), which Neighbor candidates report being tested on.
  • Write one worked example in Interview Process Design (Multi-round Interviews) and time yourself on it.

Deliverable: One timed worked example in Interview Process Design (Multi-round Interviews).

Day 5 — Answer out loud: Coding & Algorithmic Problem Solving

  • Answer aloud, timed: Implement a function to find the shortest path between host locations and a renter's search coordinate within a specific radius.
  • Answer aloud, timed: Design an algorithm to detect duplicate listings or fraudulent host accounts based on shared metadata.

Deliverable: Spoken answers to 2 reported Coding & Algorithmic Problem Solving question(s), under time.

Day 6 — Answer out loud: System Design & Marketplace Architecture

  • Answer aloud, timed: How would you design a real-time messaging system between hosts and renters that ensures privacy and safety?
  • Answer aloud, timed: Design a scalable payment and payout system that handles security deposits, monthly recurring billing, and host disbursements.

Deliverable: Spoken answers to 2 reported System Design & Marketplace Architecture question(s), under time.

Day 7 — Answer out loud: Behavioral & Cultural Alignment

  • Answer aloud, timed: Why are you specifically interested in Neighbor, and how do you see yourself contributing to our marketplace growth?
  • Answer aloud, timed: Describe a time when you had to work long hours or go above and beyond to meet a critical project deadline. What was the outcome?

Deliverable: Spoken answers to 2 reported Behavioral & Cultural Alignment question(s), under time.

Behavioural preparation

Behavioural rounds judge the decision you made and what it cost.

Why are you specifically interested in Neighbor, and how do you see yourself contributing to our marketplace g

Medium · Behavioral & Cultural Alignment

Why are you specifically interested in Neighbor, and how do you see yourself contributing to our marketplace growth?

Approach

  1. Pick a story where you made the decision, not one where you watched it.
  2. State the situation in two sentences and spend the rest on the reasoning.
  3. Give the blast radius: what could have broken, and what you measured.
  4. 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 had to work long hours or go above and beyond to meet a critical project deadline. Wh

Medium · Behavioral & Cultural Alignment

Describe a time when you had to work long hours or go above and beyond to meet a critical project deadline. What was the outcome?

Approach

  1. Pick a story where you made the decision, not one where you watched it.
  2. State the situation in two sentences and spend the rest on the reasoning.
  3. Give the blast radius: what could have broken, and what you measured.
  4. 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 ambiguity when project requirements change rapidly or are not fully defined?

Medium · Behavioral & Cultural Alignment

Approach

  1. Pick a story where you made the decision, not one where you watched it.
  2. State the situation in two sentences and spend the rest on the reasoning.
  3. Give the blast radius: what could have broken, and what you measured.
  4. 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 disagreed with a technical decision made by a manager or peer. How did you resolve it

Medium · Behavioral & Cultural Alignment

Tell me about a time you disagreed with a technical decision made by a manager or peer. How did you resolve it?

Approach

  1. Pick a story where you made the decision, not one where you watched it.
  2. State the situation in two sentences and spend the rest on the reasoning.
  3. Give the blast radius: what could have broken, and what you measured.
  4. 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 drives your passion for software engineering, and how do you balance high-volume output with code quality

Medium · Behavioral & Cultural Alignment

What drives your passion for software engineering, and how do you balance high-volume output with code quality?

Approach

  1. Pick a story where you made the decision, not one where you watched it.
  2. State the situation in two sentences and spend the rest on the reasoning.
  3. Give the blast radius: what could have broken, and what you measured.
  4. 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?