Palantir
Hard
Software EngineerDesign an internal interest-matching platform
System Design
52
0
July 15, 2025
Scalability Interview Questions
Scalability questions test whether you can design systems that handle growing load without degrading performance.
Expect questions on horizontal vs vertical scaling, database sharding, data partitioning strategies, and capacity planning.
Interviewers look for awareness of bottlenecks, trade-offs between consistency and throughput, and practical experience with scaling patterns.
1121Questions
202Companies
Easy 55 • Medium 583 • Hard 483Difficulty mix
Common scalability interview patterns
- Horizontal vs vertical scaling trade-offs
- Database sharding strategies (hash, range, geographic)
- Read replicas and write scaling
- Stateless service design for horizontal scaling
- Auto-scaling policies and capacity planning
- Data partitioning and rebalancing
Scalability interview questions
Filter and sort
Anthropic
Medium
Software EngineerDesign an LLM-based binary classifier
ML System Design
29
0
September 6, 2025
Snowflake
Easy
Software EngineerDesign a disk-backed KV store under contention
System Design
67
0
March 1, 2026
OpenAI
Medium
Software EngineerDesign a distributed crossword fill solver
System Design
36
0
January 17, 2026
Uber
Medium
Software EngineerDesign an Uber Eats Cart Service
System Design
68
0
May 7, 2026
Snowflake
Hard
Software EngineerDesign a multi-tenant quota system
System Design
39
0
September 6, 2025
Rippling
Medium
Software EngineerDesign centralized log ingestion and query system
System Design
61
0
January 22, 2026
Brex
Hard
Software EngineerDesign Points-from-Transactions Service
System Design
63
0
August 14, 2025
Uber
Hard
Software EngineerDesign Uber Eats-style search function
System Design
42
0
November 11, 2025
Databricks
Hard
Software EngineerDesign a thread-safe bounded queue
System Design
37
0
September 6, 2025
Airbnb
Hard
Software EngineerDesign rental watchlist and notification system
System Design
64
0
September 6, 2025
Parafin
Hard
Software EngineerDesign loan application system
System Design
63
0
August 4, 2025
OpenAI
Easy
Machine Learning EngineerHow would you build an image classifier with dirty data?
ML System Design
48
0
January 6, 2026
Rippling
Medium
Software EngineerDesign a User Behavior Tracking (Clickstream Analytics) System
System Design
41
1
June 23, 2026
OpenAI
Hard
Software EngineerDesign a Cloud DevBox Platform
System Design
54
0
April 20, 2026
Roblox
Hard
Software EngineerDesign sliding-window rate limiter with multi-keys
System Design
50
0
July 16, 2025
Datadog
Hard
Software EngineerDesign log-query stream processor
System Design
67
0
July 29, 2025
Salesforce
Medium
Software EngineerDesign a configurable monthly API rate limiter
System Design
52
0
February 12, 2026
DoorDash
Medium
Software EngineerDesign Food Ratings and Driver Payouts
System Design
61
0
February 3, 2026
Airbnb
Hard
Software EngineerDesign an Airbnb wallet with holds and payouts
System Design
41
0
September 6, 2025
Common mistakes in scalability discussions
- Jumping to scaling solutions before estimating actual load
- Ignoring the consistency implications of horizontal scaling
- Overlooking hot partition problems in sharding schemes
- Not considering the operational complexity of distributed systems
- Assuming vertical scaling is always simpler
How scalability questions are evaluated
Structured reasoning about load estimation and bottleneck identification matters most.
Show awareness of trade-offs rather than presenting a single solution.
Discuss failure modes and how the system degrades under extreme load.