Nextdoor Interview Questions
Practice 20 real interview questions from Nextdoor. Covers Coding & Algorithms, System Design, Behavioral & Leadership, Machine Learning. For roles including Machine Learning Engineer, Software Engineer, Data Engineer, Data Scientist.

"I got asked a hardcore MCM DP question and I saw it on PracHub as well. Solved that question in 5 minutes. Without PracHub I doubt I could solve it in 5 hours. Though somehow didn't get hired, perhaps I guess I solved it too fast? /s"

"Believe me i'm a student here jn US. Recently interviewed for MSFT. They asked me exact question from PracHub. I saw it the night before and ignored it cause why waste time on random sites. I legit wanna go back and redo this whole thing if I had chance. Not saying will work for everyone but there is certainly some merit to that website. And i'm gonna use it in future prep from now on like lc tagged"

"10 years of experience but never worked at a top company. PracHub's senior-level questions helped me break into FAANG at 35. Age is just a number."

"I was skeptical about the 'real questions' claim, so I put it to the test. I searched for the exact question I got grilled on at my last Meta onsite... and it was right there. Word for word."

"Got a Google recruiter call on Monday, interview on Friday. Crammed PracHub for 4 days. Passed every round. This platform is a miracle worker."

"I've used LC, Glassdoor, and random Discords. Nothing comes close to the accuracy here. The questions are actually current — that's what got me. Felt like I had a cheat sheet during the interview."

"The solution quality is insane. It covers approach, edge cases, time complexity, follow-ups. Nothing else comes close."

"Legit the only resource you need. TC went from 180k -> 350k. Just memorize the top 50 for your target company and you're golden."

"PracHub Premium for one month cost me the price of two coffees a week. It landed me a $280K+ starting offer."

"Literally just signed a $600k offer. I only had 2 weeks to prep, so I focused entirely on the company-tagged lists here. If you're targeting L5+, don't overthink it."

"Coaches and bootcamp prep courses cost around $200-300 but PracHub Premium is actually less than a Netflix subscription. And it landed me a $178K offer."

"I honestly don't know how you guys gather so many real interview questions. It's almost scary. I walked into my Amazon loop and recognized 3 out of 4 problems from your database."

"Discovered PracHub 10 days before my interview. By day 5, I stopped being nervous. By interview day, I was actually excited to show what I knew."

"I recently cleared Uber interviews (strong hire in the design round) and all the questions were present in prachub."
"The search is what sold me. I typed in a really niche DP problem I got asked last year and it actually came up, full breakdown and everything. These guys are clearly updating it constantly."
Build a model using only pandas/numpy
You are given a tabular dataset as a pandas DataFrame df with: - Feature columns (numeric and/or categorical) - A target column y (either binary class...
Design a Scalable Job Scheduler
Design a job scheduler for a small startup, then explain how you would evolve it to support roughly 100x more scheduled tasks. The system should: - Al...
Merge Weekly Time Intervals
You are given a list of time intervals within a single week. Each time is written as a day-of-week plus a 24-hour clock, for example Sat 13:00 or Mon ...
Merge overlapping weekly time intervals
You are given a list of time intervals representing meetings. Each interval is a pair of strings in the format: - "<Day> <H>:<MM>" (24-hour time) - <D...
Write SQL for app metrics
You are given a simplified schema for a photo-sharing app: - users(user_id, user_name, joined_at) - photos(photo_id, user_id, created_at) - follows(fo...
Measure Local News Launch Success
Nextdoor is considering launching a Local News feature that recommends neighborhood-specific news articles inside the app. The goal is to increase use...
Design tables for KPI dashboard
You need to design the analytical data model behind a KPI dashboard for a large-scale photo-sharing app. Raw source tables: - users(user_id, user_name...
Design KPI tables, retention, rollups, timezone
You are building a fast KPI dashboard for Nextagram. The raw tables are: - users(user_id PK, username, created_at TIMESTAMP) - photos(photo_id PK, use...
Flatten Nested Comments
You are given a list of top-level posts, where each post may contain a list of nested comments, and each comment may itself contain more nested replie...
Write SQL for basic user metrics
You are given a simplified schema for a fictional social app called Nextagram: - users(user_id PK, username, created_at TIMESTAMP) - follows(follower_...
Describe CAP, distributed systems, multithreading experience
CAP Theorem, Distributed Systems Design Decisions, and Multithreading Context Provide a structured answer that both explains the concepts and shows ho...
Build Ranked Feed With Photo Batching
You are given a list of feed objects. Each object has: - id: a unique string - type: one of Normal, Video, or Photo - score: a numeric ranking score C...
Implement ordering with dependency constraints
You are given n items labeled 0..n−1 and a list of precedence constraints edges[i] = [u, v] meaning u must appear before v. Return a valid ordering of...
Implement and use a version comparator
You are given up to 100,000 version-like identifiers (e.g., "1.0", "01.2.0", "2.0.0-alpha", "1.10.3"). Implement compare(a, b) that orders identifiers...
Which culture principle resonates and why
Culture-Fit Reflection: Principle, Evidence, and Thoughtful Critique Prompt After watching the company’s culture-fit video: 1. Select one specific pri...
Build an end-to-end ML classification pipeline
End-to-End Tabular Classification Pipeline (Python) Context You are given a tabular dataset in a CSV file and asked to build an end-to-end machine lea...
Build and evaluate a Colab classification model
End-to-End Tabular Classification Workflow in Google Colab You are asked to design and implement a complete classification workflow for a tabular data...
Implement version string comparator with extensions
Implement a function compareVersions(a, b) that compares two software version strings. Each version consists of dot-separated numeric components (e.g....
Answer HR motivation and project experience questions
You are interviewing for a technical role (e.g., software engineer, data scientist, or research engineer) at a tech company. In an HR screen, the recr...
Describe resume highlights and confirm logistics
Behavioral: Walk Through 2–3 ML Projects + Logistics Context You are interviewing for a Machine Learning Engineer role in a technical screen that emph...