Meta Interview Questions — Page 30

Meta·Data Scientist·Technical Phone Screen

Apr 2026

Meta data scientist SQL round, two questions back to back with a strict time window and some tricky edge cases baked in. The self-call exclusion and the double-counting trap in Q2 were clearly there to see if you'd actually read the problem.

Given a video_calls table, find the top 10 callers by number of distinct recipients they called over the last 7 days. Exclude self-calls. Break ties by total calls, then caller_id ascending. Return caller_id, distinct recipient count, and total calls.
Using a daily_users table joined with video_calls, calculate what percentage of active French users (dau_flag = 1) on a specific date appeared as either a caller or recipient in at least one call that same day. Return the numerator, denominator, and the percentage.

“The tie-breaking part is where I almost slipped up.”

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Meta·Software Engineer·Onsite - Behavioral / Leadership

Apr 2026

Behavioral round at Meta for a management consulting role. Just one question but it had some real teeth to it, the kind where you can tell they're probing for how you actually think about tradeoffs rather than just whether you can tell a tidy story.

Describe a situation where you pushed for a long-term approach even when there was pressure to go for a quick fix. How did you handle stakeholder expectations along the way?

“I had a decent example ready but fumbled the stakeholder piece a bit.”

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Meta·Software Engineer·Technical Phone Screen

Apr 2026

Meta SWE interview with a stack-based simulation problem. Pretty standard coding round, nothing too wild, but the details matter more than they look.

Given logs of function calls on a single-threaded CPU, each log containing a function ID, whether it's a start or end event, and a timestamp, compute the exclusive execution time for each function (not counting time spent in functions it called).

“The stack part clicked pretty fast for me but I fumbled the off-by-one on end timestamps for a bit.”

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Meta·Software Engineer·Onsite - Coding / Algorithms

Apr 2026

Meta SWE onsite coding round, basically a warm-up question that still has enough sharp edges to trip you up if you haven't drilled it recently. The follow-ups are where they actually separate candidates.

Implement an LRU Cache with O(1) get and put operations, including capacity-based eviction.
How would you make the LRU Cache thread-safe? What are the tradeoffs between a coarse lock and a more granular approach?
Can you extend this to an LFU Cache? How does the eviction logic change?
How would you add TTL (time-to-live) expiration to the cache?

“Classic LC 146.”

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Meta·Data Scientist·Technical Phone Screen

Apr 2026

Meta data science interview with a meaty stats/behavioral question about skewed distributions and cohort dynamics. Single question but it had four sub-parts that kept branching into more nuance than I expected.

Daily shares per user follow a right-skewed distribution with a long tail. On Day 1, split users into two cohorts based on where they fall in that distribution: around the median versus around the 95th percentile. Over the following two weeks, how would you expect each cohort's average daily shares to change, and what role does regression to the mean play versus actual behavioral differences? Which cohort would show more day-to-day variance and why? How would weekly seasonality show up in the cohort time series and how would you control for it? Finally, outline an approach to test whether these percentile-based cohorts remain stable over time.

“This one sprawled.”

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Meta·Product Manager·Onsite - Product Sense / Strategy

Apr 2026

PM interview at Meta focused on product analytics. Just the one question but it had a lot of layers to it and I felt like I only scratched the surface in the time I had.

As a PM at Meta, how would you define and measure success for Facebook's onboarding and sign-up experience?

“I jumped straight to activation rate and kind of stayed there too long.”

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Meta·Software Engineer·Onsite - System Design / Architecture

Apr 2026

Meta system design round focused entirely on the classic news feed problem. The depth of follow-up questions made it clear they weren't just looking for a textbook answer, they wanted you to actually defend your choices under pressure.

Design Instagram (or a Facebook-style news feed) with personalized ranking at scale, supporting photo/video posts, follows, likes, and comments for roughly a billion daily active users.
Walk through how you'd handle the 'hot key' problem when a single celebrity post goes viral and hammers your cache layer.
How would you design the ranking layer for a personalized feed? Walk through candidate generation through to the final ranked result.
How do you handle cache invalidation when a user unfollows someone or a post gets deleted?

“The part that tripped me up wasn't the storage or the read path, it was justifying the fan-out strategy without just reciting the hybrid answer.”

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Meta·Software Engineer·Technical Phone Screen

Apr 2026

Meta Research Scientist coding round, two problems back-to-back in 40 minutes. Pretty standard algorithmic stuff but the time pressure was real and I left feeling like I could've communicated my thinking better on the second one.

Given an array of k sorted linked lists, merge them all into a single sorted linked list.
Return the vertical order traversal of a binary tree, ordered from top to bottom within each column and left to right when nodes share the same row and column.

“I went straight for the min-heap approach and it landed fine.”

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Meta·Software Engineer·Onsite - Coding / Algorithms

Apr 2026

Six coding problems back to back for a Meta SWE round, heavy on trees and graphs with some greedy/DP mixed in. The questions weren't impossible but the breadth meant you had to context-switch fast, and a couple of the follow-ups (especially the flight cost one) required more thought than I expected.

Given the root of a binary search tree and two integers representing a range, return the sum of all node values that fall within that range. How would you use DFS with BST-specific pruning, and what are the time and space complexities?
Given a binary tree (not necessarily a BST) and two nodes p and q that are guaranteed to exist, return their lowest common ancestor. Walk through both recursive and iterative approaches and compare their complexities.
You have a list of departure flights and a list of return flights, each with a date and price. Find one departure and one return such that the return date is strictly after the departure date and the combined price is minimized. Design an O(n) solution if inputs are pre-sorted by date, and describe an O(n log n) approach otherwise.
Given a binary tree, count how many nodes have a value equal to the floor of the average of all values in their subtree (including themselves). Provide an O(n) solution.
Given a binary grid of 0s and 1s and a starting cell, return all cells 4-directionally connected to the starting cell with the same value. As a follow-up, return the border neighbors: cells adjacent to the component that are not part of it. Discuss BFS vs DFS trade-offs and analyze complexity.
Given a binary tree, determine whether it represents a valid max-heap. This requires checking both the completeness property (levels filled left to right with no gaps) and the heap-order property (every node is greater than or equal to its children). Implement an O(n) BFS-based solution and explain why DFS alone can fail to catch completeness violations.

“Pretty standard BST problem.”

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Meta·Technical Program Manager·Onsite - Behavioral / Leadership

Apr 2026

Interviewed at Meta for a TPM role and got hit with a negotiation-with-senior-leaders behavioral question. Pretty standard for the level but it still made me sweat a little.

Describe a difficult situation where you had to negotiate with senior leadership. What happened and what did you take away from it?

“I had a decent story ready but I spent too long on the setup and rushed the actual negotiation part, which is obviously the whole point of the question.”

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