Scale AI Interview Questions
Practice 34 real Scale AI interview questions for 2026. Scale AI interview questions for Software Engineer and Machine Learning Engineer roles with detailed solutions — a focused guide to interview preparation that emphasizes coding, system design, and production ML skills. Expect a heavy coding and architecture bar: Coding & Algorithms and ML System Design questions appear first in onsite loops, followed by Behavioral & Leadership, Machine Learning, and Software Engineering Fundamentals rounds. For Software Engineer candidates you’ll be evaluated on algorithmic correctness, API and data-pipeline design, production-quality implementation, and clear impact storytelling during behavioral rounds. Drill the recurring technical themes shown here: for Software Engineers, common problems center on designing LLM API pipelines and CSV ingestion endpoints that call classification/embedding services, building task scheduling and task-processor logic, implementing data-aggregation/time-window computations and tree/graph algorithms like LCA via DFS, plus leadership/STAR impact questions. For Machine Learning Engineers, expect Transformer internals and implementations (multi-head attention, decoding and sampling), post-training methods and tradeoffs (fine-tuning, RL variants), adversarial robustness experiments, and ML-pipeline debugging and text parsing. Prepare by coding end-to-end systems, practicing architecture sketches, and quantifying past impact in clear metrics.
"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."
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"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."
Design an Embedding and Classification API
Design an Embedding and Classification API Design a service that accepts text items, generates vector embeddings, and optionally classifies each item ...
Build a CSV-to-JSON Classification Service
Build a CSV-to-JSON Classification Service Build a backend service in stages. First, an HTTP request supplies a server-visible CSV path and the servic...
Design a Durable Task Scheduling Service
Design a Durable Task Scheduling Service The initial prompt is “design a task scheduler.” Begin by distinguishing an in-process timer, a durable delay...
Present a Metrics-Driven Technical Project
Present a Metrics-Driven Technical Project Choose one project you personally worked on and present it to a general software-engineering audience. The ...
Design a Streaming Job Scheduler
Design and incrementally build a streaming job scheduler: a service (and supporting class) that continuously ingests tasks and dispatches them to work...
Design an LLM API pipeline
You are asked to build a small application feature that calls a hosted large language model (LLM) API to solve a user task. The interviewer is not int...
Connect Your Hardest Project to Your Interest in a Role
Connect Your Hardest Project to Your Interest in a Role Give a concise self-introduction that explains why this company and role interest you. Then us...
Design pipeline using classification and embedding services
You are given two black-box ML services: 1. Classification Service - Input: One or more text documents. - Output: A label for each document (e.g...
Design CSV upload endpoint with GPT classification
This question evaluates backend engineering skills including HTTP API design, multipart file handling, CSV parsing and serialization, local JSON persi...
Debug ML pipeline and build text parser
You are in a hands-on, hour-long ML-engineering working session (Scale AI, Machine Learning Engineer loop). You are given a small ML project — data lo...
Debug a Project Assignment Codebase
This question evaluates debugging, state management, test-driven troubleshooting, data filtering correctness, and the ability to maintain a public API...
Implement a Dependency-Aware Task Scheduler
Implement a TaskManager class with two methods: - AddTasks(tasks): add one or more tasks into the system. - ConsumeTask(): return and remove the execu...
Explain worker state machine load balancer design
You are designing a lightweight load balancer for a Python-based backend service that dispatches tasks to a pool of worker processes. Describe how you...
Answer common project leadership questions
Prepare concise, structured answers for a behavioral interview covering these themes: - A project you are most proud of - Feedback you received and ho...
Handle customer engagement and manager-rating questions
In a behavioral round focused on customer engagement / leadership principles, you are asked questions like: - “Tell me about a time you worked directl...
Explain LLM post-training methods and tradeoffs
This question evaluates a practitioner's knowledge of LLM post-training methods—including supervised fine-tuning, preference optimization approaches (...
Describe how you learn quickly in new domains
Interview-style behavioral question: "Tell me about a time you had to learn something very quickly in order to succeed in a project or role. How did y...
Design a large-scale ticketing system
Design an online ticketing system similar to Ticketmaster that supports very high concurrency for popular events where many users try to purchase tick...
Explain Transformers, attention, decoding, RL, and evaluation
Technical Screen: Transformers, Attention, Decoding, RLHF, Evaluation, and Optimization Context: Assume a modern decoder-only LLM unless stated otherw...
Quantify impact of your projects using STAR
Interview-style behavioral prompt: "Pick one or two of your impactful projects and walk me through them in detail. Focus on what you did and how you m...