Meta interview notes, page 24 of 238

FAANG / Big Tech

Most of these Meta write-ups come from Software Engineers (1,194), then Data Scientists (489) and Product Managers (453). The most reported rounds are the technical phone screen (1,190), the product sense round (466), the system design round (255) and the behavioral / leadership round (205).

2377 interview notes · updated Jul 2026

Meta·Software Engineer·Onsite - Coding / Algorithms

Apr 2026

Meta SWE coding round, one question the whole time, pretty focused on array manipulation and then they pushed into a generalization discussion at the end. Felt manageable but the heap follow-up is where things got interesting.

Given three sorted arrays, merge them into a single sorted array in O(n_a + n_b + n_c) time using three pointers. Then generalize your approach to merging k sorted arrays.

“Three pointers part was fine, I'd done something similar before.”

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Meta·Software Engineer·Technical Phone Screen

Apr 2026

Meta Research Scientist interview with a pretty meaty algorithms question about sparse data structures. One question but it had a lot of layers to it, and the follow-up on matrices caught me a bit flat-footed.

Given two sparse vectors (and as a follow-up, two sparse matrices), design a data representation and an algorithm to compute their dot product or matrix product efficiently. Walk through your choice of representation, time and space complexity in terms of non-zero entries, and the trade-offs involved.

“I went with list of (index, value) pairs for the vector case and talked through a two-pointer merge approach.”

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Meta·Software Engineer·Online Assessment (OA)

Apr 2026

Meta SWE coding round with an AI-assisted twist. The task was to take source code or an IR representation of a small compiled language and apply compiler optimizations to cut memory and runtime. Felt more like a compilers course exam than a typical coding interview, which I did not fully anticipate.

Given the source code or intermediate representation of a small compiled language, implement compiler optimizations to reduce both memory usage and execution time. Sub-tasks include constant folding and propagation, dead-code elimination, common subexpression elimination, variable reuse, and reordering of independent operations. Pass as many test cases as possible within the time limit. An AI coding assistant is allowed but not required.

“I leaned on the AI assistant more than I should have for the dead-code elimination part and it gave me something that passed maybe two thirds of the cases but missed edge cases around loops.”

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Meta·Product Manager·Onsite - Behavioral / Leadership

Apr 2026

Interviewed at Meta for what seemed like a leadership-focused round. Just one question but it was meaty enough to take up a good chunk of time.

How do you get a team excited about and aligned on an idea you're pushing?

“I went with a story about a time I had to convince a skeptical engineering lead on a roadmap shift.”

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Meta·Software Engineer·Onsite - System Design / Architecture

Apr 2026

Meta system design round, just one question about building an LRU cache. Felt pretty short but they go deep fast.

Design an LRU cache.

“Started with a hashmap plus doubly linked list, which is the obvious path, and they pushed pretty quickly on eviction edge cases and thread safety.”

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Meta·Software Engineer·Onsite - Behavioral / Leadership

Apr 2026

Meta behavioral round for a software engineer role, four questions all in the standard ownership-and-impact mold. Nothing shocking but you really do need concrete stories ready, vague answers get probed hard.

What project are you most proud of, and what made it meaningful to you?
Tell me about a conflict you had with a peer or someone from another team, and how you handled it.
Describe a time when project requirements were unclear and you had to figure out what to actually build.
What feedback have you gotten from managers or peers, and what did you actually do with it?

“This sounds easy until you're sitting there and every project suddenly feels either too small or too hard to explain quickly.”

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Meta·Software Engineer·Technical Phone Screen

Apr 2026

Short Meta SWE coding round, just one tree problem. Nothing crazy but it's the kind of question that feels easy until you're actually writing it out.

Given a binary tree, print its left view (the first node visible at each level when viewed from the left side).

“My first instinct was DFS and just tracking the first node at each depth, which works fine.”

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Meta·Software Engineer·Onsite - System Design / Architecture

Apr 2026

Meta system design round focused entirely on building an auction platform layered on top of a social network. Dense problem with a lot of moving parts, and I felt like I was playing catch-up the whole time.

Design an auction platform built on top of a social network like Instagram, where sellers list items with a start/end time and reserve price, bidders place bids during the active window, and the highest valid bid at close wins.
How would you handle anti-sniping rules and ensure fairness for bids placed in the final seconds of an auction?
Walk through how you'd hand off payment processing once an auction closes, and how you'd handle failures in that flow.
How would you design the notification system to alert bidders and sellers about auction events in real time?
How would you scale this system to support a large number of concurrent auctions running simultaneously?

“I started with the data model because it felt like the safest ground.”

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Meta·Software Engineer·Technical Phone Screen

Apr 2026

Meta SWE coding round focused on extending a maze solver with direction-restricted cells. Pretty much a pure algorithmic problem with a clear setup but a tricky extension that required thinking carefully about state and BFS traversal logic.

You have a working BFS-based maze solver on a 2D grid with walls, open cells, a start, and an end. Some cells now have movement restrictions, like blocking backward movement or only allowing certain directions. Modify the BFS expansion logic so it only enqueues neighbors that are permitted from the current cell, and update the tests to cover the new behavior.

“The base BFS part was fine, I've done that enough times.”

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Meta·Product Manager·Onsite - Product Sense / Strategy

Apr 2026

Interviewed at Meta for a product role and got hit with a misinformation measurement question that felt deceptively open-ended. Not a lot of context in what I can share but it was a product sense round and it pushed hard on metrics thinking.

How would you measure the success of initiatives aimed at reducing misinformation on Facebook?

“I went straight to engagement metrics and then realized mid-answer that was probably the wrong instinct for a trust and safety problem.”

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