Dataford
Top 11
Prep plan
Updated weekly · Last refresh Sep 24

Wise. Energy Backend Engineer Interview Questions

The questions to prepare for a Wise. Energy Backend Engineer interview. Questions from real interview reports rank first. Updated daily.

11questions
~2htotal time
Track your progressSign up free to work through all 11 questions and resume where you left off.
Start practicing free →
1
CodingStart here. 4 questions · ~33 min
Circuit Breaker for Remote CallsHard

Tests your ability to design resilient service-to-service communication and failure handling in a backend system.

javaWise. Energy
Exchange Rate Service ImplementationMedium

Evaluates your ability to design and implement core backend functionality for multi-currency transactions.

Wise. Energy
Thread Safety With Shared StateHard

Assesses your concurrency skills and ability to prevent race conditions and visibility issues.

thread safetyconcurrencyWise. Energy
More Coding questions with a free account
2
System Design4 questions · ~33 min
Choosing LRU Eviction PolicyMedium

Assesses your understanding of cache eviction trade-offs and workload-driven decision making.

performancelru cacheWise. Energy
Database Scaling BottlenecksMedium

Evaluates your knowledge of database scaling constraints and how they impact backend performance.

performancebottlenecksWise. Energy
Distributed Cache InvalidationHard

Tests your ability to maintain cache correctness under distributed concurrency and partial failures.

distributed systemsdata consistencyWise. Energy
More System Design questions with a free account

Sign up to see every question

Create a free account to unlock this list and practice real interview questions.

Get my prep plan
3
More topics3 questions · ~25 min
Composition vs Inheritance Trade-offsMedium

Assesses your ability to choose appropriate OOP design patterns and justify maintainability decisions.

project experienceWise. Energy
Optimizing Queries for Large DatasetsHard

Tests your ability to improve SQL performance using indexing, query planning, and data access strategies.

large datasetsperformancequery optimizationWise. Energy
More questions with a free account
Hands-on SQL practiceWrite and run real queries in the editor. 3 drills · ~30 min
7-Day Rolling Active UsersMedium
Practice
Practice drill

Compute daily active users and a 7-day rolling average using a CTE, distinct counts, and window functions.

Window FunctionsDate FunctionsRunning TotalsMetaSpotifyMeta IT
Compare Monthly User Retention CohortsMedium
Practice
Recently asked
Practice drill

Calculate month-1 retention for January vs February signup cohorts using joins, date filtering, and aggregation.

Window FunctionsDate FunctionsAggregationsTrideumZulilyeBay
Window Functions for Asset RankingMedium
Practice
Practice drill

Write a SQL query using window functions to find the top-performing energy assets per region over the last quarter. Use the energyassets and assetperforman...

Window FunctionsDate FunctionsRankingWise. Energy
The finish line: interview-readyComplete all 11 questions plus 3 hands-on drills to finish this plan.