HCLTech

Global IT services and consulting company.

4 Rounds ~21 Days Medium
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The Interview Loop

Recruiter Screen (30 min)

Standard fit check, behavioral questions, and resume overview.

Technical Loop (3-4 Rounds)

Deep dive into domain knowledge, coding, and system design.

Interview Question Bank

Backend Engineer System Design hard

Design an API Rate Limiter for a multi-tenant enterprise application to prevent abuse.

#Distributed Systems #Algorithms #Redis
Backend Engineer System Design medium

Compare Kafka and RabbitMQ. When would you choose Kafka over RabbitMQ for an event-driven architecture?

#Message Brokers #Event Streaming #Kafka
Backend Engineer System Design medium

Explain the Circuit Breaker pattern. How does it work, and how would you implement it in a Spring Boot application?

#Fault Tolerance #Resilience4j #Microservices
Backend Engineer System Design hard

How do you ensure idempotency in a REST API, specifically for a payment processing endpoint?

#API Design #Idempotency #Payments
Backend Engineer System Design medium

Explain the API Gateway pattern. What cross-cutting concerns should be handled at the API Gateway level versus the Microservice level?

#Architecture #Security #Routing
Backend Engineer System Design medium

How would you design a highly available and scalable notification service that sends Emails, SMS, and Push Notifications?

#Asynchronous Processing #Message Queues #Microservices
Backend Engineer System Design medium

Design a URL Shortener service like Bitly. Focus on the data model and the algorithm for generating the short URL.

#Scalability #Hashing #Database Design
Data Engineer System Design hard

Design a fault-tolerant data ingestion pipeline using Apache Kafka. How do you ensure exactly-once processing?

#Kafka #Fault Tolerance #Exactly-once Semantics
Data Engineer System Design hard

Design a batch processing system to ingest 5TB of application log data daily, clean it, and make it available for reporting.

#Batch Processing #Data Lake #ETL
Data Engineer System Design hard

How would you design the data model for a data warehouse supporting an e-commerce platform's sales analytics?

#Data Modeling #Star Schema #E-commerce
Data Engineer System Design hard

Design a real-time streaming pipeline to process IoT sensor data, detect anomalies, and store the results for dashboarding.

#Streaming #Kafka #Spark Streaming #NoSQL
Data Scientist System Design hard

Design a real-time fraud detection system for credit card transactions. Focus on the data ingestion, feature engineering latency, and model serving.

#Streaming Data #Real-time Processing #Kafka #MLOps
Data Scientist System Design hard

Design a personalized product recommendation system for a large retail client. Walk me through the data pipeline, model selection, and serving architecture.

#Recommendation Systems #Architecture #Scalability
DevOps Engineer System Design hard

How do you design a highly available Kubernetes cluster for a stateful application requiring persistent storage across multiple availability zones?

#Kubernetes #High Availability #StatefulSets #StorageClasses
Frontend Engineer System Design hard

Design a scalable Micro-Frontend architecture for a large enterprise e-commerce platform. How do you handle shared state and routing?

#Micro-frontends #Module Federation #Architecture
Frontend Engineer System Design medium

Design a client-side logging and error tracking system for a distributed frontend application.

#Error Handling #Logging #Monitoring
Frontend Engineer System Design hard

Design a real-time chat application interface. How do you handle state management, WebSocket connections, and offline mode?

#WebSockets #Real-time #Offline Storage
Frontend Engineer System Design medium

Design an image carousel/slider component. What data structures would you use, and how would you optimize for performance and accessibility?

#Component Design #Performance #Accessibility
Full Stack Engineer System Design medium

How would you design a scalable notification system (Email, SMS, Push) for a large enterprise client?

#Microservices #Asynchronous Processing #Third-party Integration
Full Stack Engineer System Design medium

Design a URL shortening service like Bitly. Focus on the database schema and the encoding algorithm.

#Scalability #Hashing #Database Design
Full Stack Engineer System Design hard

Design an e-commerce checkout system that can handle high traffic during a flash sale.

#High Availability #Message Queues #Concurrency
Machine Learning Engineer System Design medium

How do you deploy a PyTorch model as a scalable REST API using FastAPI and Docker?

#MLOps #Deployment #Docker #FastAPI
Machine Learning Engineer System Design hard

Design an end-to-end machine learning system to predict equipment failure (predictive maintenance) for an industrial client.

#IoT #Predictive Maintenance #Architecture
Machine Learning Engineer System Design medium

What is a Feature Store, and why is it important in enterprise ML architectures?

#MLOps #Feature Engineering #Data Architecture
Machine Learning Engineer System Design medium

How would you orchestrate a daily batch scoring pipeline on a cloud platform like Azure Machine Learning or AWS SageMaker?

#Cloud #Batch Processing #Azure/AWS
Machine Learning Engineer System Design hard

Explain your approach to setting up a CI/CD pipeline for machine learning models using GitHub Actions and MLflow.

#MLOps #CI/CD #MLflow
Machine Learning Engineer System Design hard

Design a real-time recommendation engine for an e-commerce platform. How do you handle low-latency requirements?

#Recommendation Systems #Latency #Architecture
Machine Learning Engineer System Design medium

What is the difference between concept drift and data drift? How do you monitor for them in a production ML system?

#MLOps #Model Monitoring
Product Manager System Design medium

Design a notification system that sends alerts via email, SMS, and push notifications for a critical enterprise monitoring dashboard.

#Asynchronous Processing #Message Queues #Scalability
Product Manager System Design hard

Design a high-level architecture for a B2B ticketing system used by IT support agents.

#Microservices #Databases #Scalability
Product Manager System Design hard

Design a scalable document storage and retrieval system for a legal compliance product.

#Storage #Search #Security
Product Manager System Design hard

Design an API rate-limiting system for a SaaS product to prevent abuse by free-tier users.

#APIs #Security #Algorithms

Difficulty Radar

Based on recent AI-sourced data.

Meet Your Interviewers

The "Standard" Interviewer

Senior Engineer

Focuses on core competencies, system constraints, and clear communication.

Simulate

Unwritten Rules

Think Out Loud

Always explain your thought process before writing code or drawing architecture.

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