Airbnb Senior+ Software Engineer Interview Experience — Passed Every Round, Then the Role Was Filled

Background: US bachelor's degree, 4.5 years of experience.

Timeline

• Mid-October: mass-applied on LinkedIn to Airbnb Beijing (the "air mattress" company) — got a recruiter email the same day.
• A week later: 15-minute HR Screen introducing the role.
• Late October: 45-minute Tech Screen.
• Early November: VO1 (Coding 1) and VO2 (Coding 2), 45 minutes each.

Suggest a split stay where you stay at 2 different houses, one for the first part of your trip and the other for the remainder. Make an API endpoint that will return all possible combos of split stays across 2 listings for a given date range. Give each listing a name ("A", "B", etc.) and our availability will just be a list of day numbers.

For example: A - [1,2,3,6,7,10,11]; B - [3,4,5,6,8,9,10,13]; C - [7,8,9,10,11]

Given the date range [3-11], the expected result is all sets of two Airbnbs that could form a split stay: [B, C]

Brute force solution; extra credit for writing a bitmask solution.

Reference brute-force solution:

from itertools import combinations

def find_splits(listings, start_date, end_date):
    desired_days = set(range(start_date, enddate+1))
    splits = []
    for a,b in combinations(listings.keys(), 2):
        a_set = set(listings[a])
        b_set = set(listings[b])
        if desired_days.issubset(a_set) or desired_days.issubset(b_set):
            continue
        combined_days = set(listings[a]) | set(listings[b])
        if desired_days.issubset(combined_days):
            splits.append((a,b))
    for a in listings.keys():
        a_set = set(listings[a])
        if desired_days.issubset(a_set):
            splits.append((a))
    return splits

listings = {"A": [1,2,3,6,7,10,11], "B":[3,4,5,6,8,9,10,13], "C":[7,8,9,10,11]}
print(find_splits(listings, 3,11))
print(find_splits(listings, 11,11))

• Mid-November: VO3 (Tech Experience Interview), 45 minutes, deep dive into resume projects.
• Mid-November: VO4 (45-minute System Design).
  • Host page — pick a date range, aggregate info: nights booked out; average price.
  • Assume 3 tables: Listings; Reservations; Pricing.
  • When a host has 100+ listings, the page gets slow — how would you optimize the underlying design?
• Late November: 45-minute HM interview, deep dive into resume projects + behavioral.
  • Describe an experience collaborating with other teams / where an internal ETA wasn't met and it caused impact, or the timeline slipped or scope got cut.
  • How did you identify the root cause?
  • How was the team divided up on the project?
  • Was there a backup plan to unblock at the time?
• Late November: VO5, 45-minute Core Values Interview, behavioral.
  • Walk through your background.
  • Any hobbies outside of work, or fun stories from school?
  • Why Airbnb?
  • A memorable experience using Airbnb while traveling.
  • Any tips for picking an Airbnb listing? Any bad experiences?
  • An example of communicating with yourself or across different teams.
  • How do you make sure a design project and its later rollout stay in sync with teams across different timezones/cultural backgrounds? What problems came up along the way?
  • When you started working, was there a senior who helped you a lot?
  • In an emergency, do you make sure you get dedicated communication time with your senior?
  • Looking back, what could you have done better / improved?
  • How do you manage the gap between expectations (work/life)?
  • Any adventurous moments/decisions in your life? How do you approach taking risks?
  • What's the biggest obstacle in going from just writing code to owning an entire project?
  • What obstacles/challenges/biggest uncertainties do you expect at Airbnb?
• Early December: heard back that I passed every interview, but the position had been filled — I can stay in the pool for a year.