Backend Engineer • Behavioral • hard

Describe a situation where a production deployment caused a major outage. How did you debug, resolve, and prevent it from happening again?

#Incident Management #Debugging #Post-mortems

Practice

Backend Engineer • Behavioral • medium

Give an example of a time you went above and beyond to improve the performance, scalability, or reliability of a backend system.

#Proactivity #Performance Optimization #Ownership

Practice

Backend Engineer • Behavioral • medium

Tell me about a time you had to push back on a product manager's timeline because of technical debt or architectural concerns.

#Communication #Stakeholder Management #Prioritization

Practice

Backend Engineer • Coding • medium

Machine Coding: Design a Splitwise-like application for splitting food bills among friends with exact, percentage, and equal split strategies.

#OOD #Algorithms #Design Patterns

Practice

Backend Engineer • Coding • medium

Machine Coding: Implement a cache with an LRU eviction policy and Time-To-Live (TTL) for each key.

#Doubly Linked List #HashMap #Concurrency

Practice

Backend Engineer • Coding • medium

Given a grid representing a city map with restaurants, customers, and roadblocks, find the shortest path for a delivery executive to pick up and deliver the food.

#Graphs #BFS #Shortest Path

Practice

Backend Engineer • Coding • medium

Merge K sorted arrays/lists. (Context: Merging timestamped logs from different microservices).

#Heaps #Divide and Conquer #Pointers

Practice

Backend Engineer • Coding • medium

Find the Top K frequent elements in a stream of data (e.g., finding top K trending dishes in a locality).

#Heaps #HashMaps #Bucket Sort

Practice

Backend Engineer • Coding • medium

Given an array of integers representing restaurant ratings over time, find the sliding window maximum of size K.

#Sliding Window #Deque #Arrays

Practice

Backend Engineer • Coding • easy

Find the longest palindromic substring in a given string.

#Strings #Dynamic Programming #Two Pointers

Practice

Backend Engineer • Coding • hard

You have a list of delivery executives and a list of orders. Assign orders to executives such that the total distance traveled is minimized.

#Graphs #Bipartite Matching #Hungarian Algorithm #Greedy

Practice

Backend Engineer • Coding • medium

Given a list of orders with their preparation start and end times, find the maximum number of concurrent orders being prepared at any given time.

#Arrays #Sorting #Sweep Line Algorithm

Practice

Backend Engineer • Coding • medium

Implement a Trie data structure to support fast prefix search for restaurant names.

#Trie #Trees #Strings

Practice

Backend Engineer • Coding • hard

Machine Coding: Design and implement an in-memory Food Delivery System. It should support adding restaurants, updating menus, placing orders, and assigning the nearest delivery agent.

#Object-Oriented Design #Design Patterns #Concurrency

Practice

Backend Engineer • Coding • medium

Machine Coding: Design a Promo Code / Coupon Engine. Support rules like flat discount, percentage discount, maximum cap, and user-specific usage limits.

#Strategy Pattern #Rule Engine #OOD

Practice

Backend Engineer • System Design • hard

Design a surge pricing engine for Swiggy that dynamically adjusts delivery fees based on weather, traffic, and real-time demand-supply gaps in specific geohashes.

#Stream Processing #Distributed Systems #Event-Driven Architecture

Practice

Backend Engineer • System Design • medium

Design a system to handle Swiggy One memberships, ensuring benefits (like free delivery) are applied correctly at checkout with minimal latency.

#Caching #Microservices #Rule Engines

Practice

Backend Engineer • System Design • hard

Design a location-based service to find the nearest delivery executives for order assignment.

#Geospatial Indexing #QuadTrees #Geohash #Redis Geospatial

Practice

Backend Engineer • System Design • hard

Design a payment processing gateway integration system that handles third-party gateway timeouts and failures gracefully.

#Payments #Idempotency #Reconciliation #State Machines

Practice

Backend Engineer • System Design • medium

Design a highly available notification system to send SMS, Email, and Push notifications for order lifecycle events.

#Asynchronous Processing #Message Queues #Retry Mechanisms

Practice

Backend Engineer • System Design • hard

Design Swiggy's cart and checkout service. How do you handle concurrent modifications from multiple devices and out-of-stock scenarios during checkout?

#State Management #Data Consistency #Saga Pattern

Practice

Backend Engineer • System Design • hard

Design a restaurant search and recommendation system that supports typo-tolerance, prefix matching, and personalized ranking.

#Elasticsearch #Information Retrieval #Microservices

Practice

Backend Engineer • System Design • medium

Design a distributed rate limiter for Swiggy's public APIs to prevent abuse and manage tiered API access.

#Rate Limiting #Redis #Algorithms

Practice

Backend Engineer • System Design • hard

Design Swiggy Instamart's inventory management system to handle high concurrency during flash sales or peak hours without overselling.

#Concurrency #Distributed Locks #Database Isolation #Caching

Practice

Backend Engineer • System Design • hard

Design Swiggy's real-time delivery tracking system where customers can see the live location of their delivery executive.

#WebSockets #Kafka #Redis #Geospatial Data

Practice

Backend Engineer • Technical • medium

What is the CAP theorem and how does it apply to Swiggy's cart service versus its payment service?

#CAP Theorem #Distributed Systems #Trade-offs

Practice

Backend Engineer • Technical • hard

How would you handle distributed transactions across the Order, Payment, and Inventory microservices at Swiggy?

#Microservices #Saga Pattern #Two-Phase Commit #Eventual Consistency

Practice

Backend Engineer • Technical • medium

Explain how you would optimize a slow-performing SQL query that fetches order history for a user.

#Database Indexing #Query Execution Plan #Partitioning

Practice

Backend Engineer • Technical • hard

Low-Level Design: Design a wallet system where users can add money and pay for orders. Ensure ACID properties are maintained.

#Database Design #Transactions #Concurrency

Practice

Backend Engineer • Technical • hard

How does Kafka ensure exactly-once semantics, and how would you use it for Swiggy's order state machine?

#Kafka #Messaging Systems #Idempotency

Practice

Backend Engineer • Technical • hard

Low-Level Design: Design a distributed task scheduler that can execute tasks at a given time or periodically (similar to Quartz).

#Priority Queues #Concurrency #Distributed Systems

Practice

Backend Engineer • Technical • medium

Explain the internal working of ConcurrentHashMap in Java and how it differs from Collections.synchronizedMap.

#Java #Concurrency #Data Structures

Practice

Backend Engineer • Technical • medium

Low-Level Design: Design an elevator system for a multi-story building that optimizes for minimum wait time.

#State Machine #Algorithms #OOD

Practice

Backend Engineer • Technical • medium

Low-Level Design: Design a thread-safe database connection pool from scratch.

#Concurrency #Multithreading #Resource Management

Practice

Backend Engineer • Technical • medium

How do you implement distributed locking using Redis to prevent double-booking of a limited Instamart item?

#Redis #Distributed Locks #Concurrency

Practice

Cloud Engineer • Behavioral • medium

At Swiggy, developers sometimes push back against security policies, asking for full admin access to production to debug faster. How do you handle this pushback?

#Communication #Security #Empathy

Practice

Cloud Engineer • Behavioral • easy

Describe a project where you significantly reduced cloud infrastructure costs. What was your approach?

#Cost Optimization #Initiative #Cloud Architecture

Practice

Cloud Engineer • Behavioral • medium

Tell me about a time you made a mistake that caused a production outage. How did you handle it, and what did you learn?

#Accountability #Learning #Incident Management

Practice

Cloud Engineer • Behavioral • medium

Tell me about a time you handled a major production incident. Walk me through your exact steps from the moment the pager went off to the post-mortem.

#Incident Response #Communication #Post-mortem

Practice

Cloud Engineer • Coding • medium

Write a Bash or Python script to find all unattached EBS volumes in an AWS region and delete them if they have been unattached for more than 7 days.

#Python #Boto3 #AWS EBS #Automation

Practice

Cloud Engineer • Coding • easy

Write a shell command or short script to parse an Nginx access log file and output the top 10 IP addresses that made the most requests.

#Bash #Linux #Log Parsing #Awk

Practice

Cloud Engineer • Coding • medium

Write a Terraform module to provision an S3 bucket that enforces Swiggy's compliance rules: it must be private, encrypted at rest with KMS, and have versioning enabled.

#Terraform #AWS S3 #KMS

Practice

Cloud Engineer • Coding • medium

Write a Python script using Boto3 to list all AWS IAM users who have access keys older than 90 days and output them to a CSV file.

#Python #Boto3 #AWS IAM #Security

Practice

Cloud Engineer • Coding • medium

Write a Bash or Python script that takes a list of 100 Swiggy API endpoints, checks their HTTP status concurrently, and prints only the ones that return a non-200 status.

#Python #Concurrency #Bash #Networking

Practice

Cloud Engineer • System Design • medium

Design a CDN and caching strategy to serve millions of restaurant menus and food images with ultra-low latency across India.

#CDN #CloudFront #Caching #S3

Practice

Cloud Engineer • System Design • medium

Design an auto-scaling strategy for background worker nodes that allocate delivery partners to orders, based on the backlog of orders in an SQS queue.

#AWS SQS #Auto Scaling #KEDA #Kubernetes

Practice

Cloud Engineer • System Design • hard

Design a multi-region active-active architecture on AWS for Swiggy's core order management system to ensure high availability during a regional outage.

#AWS #Global Accelerator #DynamoDB Global Tables #Route53

Practice

Cloud Engineer • System Design • hard

Design the cloud infrastructure for Swiggy Instamart's real-time inventory system. It needs to handle high read/write throughput and ensure items aren't oversold.

#AWS #Redis #Kafka #Databases

Practice

Cloud Engineer • System Design • hard

Design a rate-limiting service at the API Gateway level to protect Swiggy's backend services from abuse or DDoS attacks during New Year's Eve.

#Rate Limiting #API Gateway #Redis #Algorithms

Practice

Cloud Engineer • System Design • medium

Design a monitoring and alerting setup using Prometheus and Grafana to track the latency of Swiggy delivery partner location updates.

#Prometheus #Grafana #Metrics #SLIs/SLOs

Practice

Cloud Engineer • System Design • hard

Swiggy uses Kafka extensively for event streaming (e.g., order state changes). How do you architect a highly available Kafka cluster across multiple Availability Zones?

#Kafka #High Availability #Zookeeper/KRaft #AWS

Practice

Cloud Engineer • Technical • medium

For Swiggy's core checkout service, would you recommend a Blue/Green deployment or a Canary deployment? Explain how you would implement your choice in Kubernetes.

#Kubernetes #Canary #Blue/Green #Istio

Practice

Cloud Engineer • Technical • hard

An order placed on Swiggy touches 15 different microservices. How do you implement distributed tracing to find out exactly which service is causing a 3-second delay?

#Distributed Tracing #OpenTelemetry #Jaeger #Microservices

Practice

Cloud Engineer • Technical • medium

Swiggy engineers are complaining about 'alert fatigue' because they receive hundreds of PagerDuty alerts daily that resolve themselves. How do you fix this?

#Alerting #SRE #Incident Management

Practice

Cloud Engineer • Technical • medium

If a new deployment causes a severe memory leak in production, how do you ensure the system automatically rolls back to the previous stable version?

#Kubernetes #Argo Rollouts #Prometheus #Automated Rollback

Practice

Cloud Engineer • Technical • medium

How do you securely manage and inject secrets (like database passwords and API keys) into Kubernetes pods without hardcoding them in Git?

#Kubernetes #Secrets Management #HashiCorp Vault #AWS Secrets Manager

Practice

Cloud Engineer • Technical • medium

Design a modern GitOps CI/CD pipeline for a Golang microservice at Swiggy using tools like GitLab CI, Docker, and ArgoCD.

#GitOps #ArgoCD #Docker #Pipelines

Practice

Cloud Engineer • Technical • easy

A developer pings you saying their Kubernetes pod is stuck in a CrashLoopBackOff state. Walk me through the exact kubectl commands and steps you would use to debug this.

#Kubernetes #Debugging #kubectl

Practice

Cloud Engineer • Technical • medium

We have multiple AWS accounts for different Swiggy environments (Dev, QA, Prod) and business units. Would you use VPC Peering or AWS Transit Gateway to connect them, and why?

#AWS VPC #Transit Gateway #Network Architecture

Practice

Cloud Engineer • Technical • hard

Explain how you would handle a split-brain scenario in a distributed caching system like Redis, which Swiggy uses heavily for session management and menu caching.

#Redis #Distributed Systems #High Availability

Practice

Cloud Engineer • Technical • medium

Swiggy's AWS bill is growing rapidly. What strategies would you implement to optimize costs for our EC2 and EKS workloads without impacting performance?

#Cost Optimization #Spot Instances #Karpenter #Graviton

Practice

Cloud Engineer • Technical • medium

How would you implement IAM least privilege for a new Swiggy Instamart microservice running on EKS that needs access to a specific S3 bucket and DynamoDB table?

#AWS IAM #IRSA #EKS #Security

Practice

Cloud Engineer • Technical • medium

During an IPL final, Swiggy experiences a massive traffic spike. You notice a sudden surge of 5xx errors on an Application Load Balancer. How do you troubleshoot and resolve this?

#AWS ALB #CloudWatch #Auto Scaling #Networking

Practice

Cloud Engineer • Technical • medium

How do you manage Terraform state in a multi-developer environment, and what happens if two engineers try to apply changes to Swiggy's infrastructure simultaneously?

#Terraform #AWS S3 #DynamoDB #State Locking

Practice

Cloud Engineer • Technical • hard

Walk me through the strategy you would use to upgrade an Amazon EKS cluster running hundreds of Swiggy microservices with zero downtime.

#Kubernetes #EKS #Zero Downtime #Node Groups

Practice

Cloud Engineer • Technical • hard

Explain how you would implement mutual TLS (mTLS) between microservices in a Kubernetes cluster using Istio, and how you would verify it is working.

#Kubernetes #Istio #mTLS #Service Mesh

Practice

Cloud Engineer • Technical • hard

Several microservices in our EKS cluster are randomly failing to resolve internal DNS names. How do you troubleshoot CoreDNS performance issues?

#Kubernetes #CoreDNS #Networking

Practice

Cloud Engineer • Technical • medium

If we use DynamoDB to store user order history, how would you design the Partition Key and Sort Key to efficiently query a user's last 10 orders?

#DynamoDB #Data Modeling #NoSQL

Practice

Cloud Engineer • Technical • hard

You notice that an AWS RDS PostgreSQL read replica is experiencing high replication lag, causing stale data on the Swiggy app. How do you troubleshoot this?

#AWS RDS #PostgreSQL #Replication #Troubleshooting

Practice

Cloud Engineer • Technical • medium

How do you secure Swiggy's internal microservices so they can communicate with each other, but cannot be accessed directly from the public internet?

#VPC #Private Subnets #Security Groups #Service Mesh

Practice

Data Engineer • Behavioral • medium

Tell me about a time your pipeline failed in production and caused a data outage or incorrect metrics. What did you do?

#Incident Management #Ownership #Post-mortems

Practice

Data Engineer • Behavioral • medium

Tell me about a time you had to optimize a slow-running data pipeline. What was the root cause and the impact?

#Performance Tuning #Impact #Problem Solving

Practice

Data Engineer • Behavioral • medium

Describe a situation where you disagreed with a product manager or data scientist about a data metric definition. How did you resolve it?

#Communication #Conflict Resolution #Stakeholder Management

Practice

Data Engineer • Coding • hard

Implement a rate limiter using the Token Bucket algorithm to throttle incoming API requests from restaurant POS systems.

#Object-Oriented Programming #Concurrency #System Design

Practice

Data Engineer • Coding • medium

Given a list of delivery partner active hours as intervals [start_time, end_time], write a function to merge all overlapping intervals to find the total active duration.

#Arrays #Sorting #Intervals

Practice

Data Engineer • Coding • hard

Write a program to find the shortest delivery route for a delivery executive given a grid with obstacles, a starting point, a restaurant location, and a customer location.

#Graphs #BFS #Pathfinding

Practice

Data Engineer • Coding • easy

Given a massive web server log file, write a script to find the top 10 IP addresses making requests to the checkout API.

#File I/O #Hash Maps #Heaps

Practice

Data Engineer • Coding • easy

Given an array of integers representing daily order counts, write a function to find the maximum sum of a contiguous subarray (Kadane's Algorithm).

#Arrays #Dynamic Programming

Practice

Data Engineer • Coding • medium

Write a Python script to parse a deeply nested JSON payload representing a complex Swiggy order (multiple items, add-ons, taxes) and flatten it into a tabular format.

#Python #JSON Parsing #Recursion

Practice

Data Engineer • System Design • medium

How would you design a deduplication system for clickstream events coming from the Swiggy app?

#Deduplication #Bloom Filters #Stream Processing

Practice

Data Engineer • System Design • hard

Design a real-time dashboard pipeline for Swiggy's restaurant partners to see live orders and daily earnings.

#Real-time Analytics #Kafka #Stream Processing #Databases

Practice

Data Engineer • System Design • hard

Design the data pipeline for Swiggy Instamart's real-time inventory management system.

#Event Sourcing #Data Consistency #Architecture

Practice

Data Engineer • System Design • hard

Design a surge pricing data model and pipeline that updates delivery fees every 2 minutes based on demand and supply.

#Micro-batching #Geospatial Data #Machine Learning Pipelines

Practice

Data Engineer • System Design • medium

Design a data lake architecture for Swiggy to store and query historical geospatial data (delivery partner pings).

#Data Lake #AWS S3 #Partitioning #File Formats

Practice

Data Engineer • Technical • medium

For Swiggy Instamart, write a query to find items that went out of stock within 1 hour of being restocked.

#Self Joins #Datetime Manipulation #Event Logs

Practice

Data Engineer • Technical • medium

How do you handle data skewness in Spark when joining a massive 'orders' table with a smaller 'restaurants' table?

#Apache Spark #Performance Tuning #Data Skew

Practice

Data Engineer • Technical • easy

Explain the difference between repartition() and coalesce() in Spark. When would you use which in a daily batch pipeline?

#Apache Spark #Partitioning #Shuffling

Practice

Data Engineer • Technical • medium

How does Spark handle memory management? Explain the difference between execution memory and storage memory.

#Apache Spark #Memory Architecture #Internals

Practice

Data Engineer • Technical • hard

You have a Spark job failing with an OutOfMemory (OOM) error. Walk me through your debugging steps.

#Apache Spark #Troubleshooting #OOM

Practice

Data Engineer • Technical • medium

What is Adaptive Query Execution (AQE) in Spark 3.0, and how would it benefit Swiggy's ETL workloads?

#Apache Spark #AQE #Optimization

Practice

Data Engineer • Technical • hard

How do you ensure exactly-once processing in a Kafka to Spark Streaming pipeline for payment transactions?

#Apache Kafka #Spark Streaming #Exactly-Once Semantics

Practice

Data Engineer • Technical • medium

What happens if a Kafka consumer fails? How are offsets managed and reassigned?

#Apache Kafka #Consumer Groups #Fault Tolerance

Practice

Data Engineer • Technical • medium

How would you handle a sudden spike in order events (e.g., during IPL finals) causing severe Kafka consumer lag?

#Apache Kafka #Scaling #Monitoring

Practice

Data Engineer • Technical • hard

Explain how watermarks work in Apache Flink and how you would use them to handle late-arriving delivery status events.

#Apache Flink #Streaming #Event Time

Practice

Data Engineer • Technical • medium

How do you design an Airflow DAG to handle backfilling of 6 months of historical order data without overloading the production database?

#Apache Airflow #Backfilling #Database Load

Practice

Data Engineer • Technical • medium

Write a SQL query to find the top 3 restaurants by order volume in each city for the last 30 days.

#Window Functions #Aggregations #Ranking

Practice

Data Engineer • Technical • medium

Explain how you would handle a scenario in Airflow where a downstream task needs to wait for multiple asynchronous external APIs to finish.

#Apache Airflow #Sensors #Asynchronous Tasks

Practice

Data Engineer • Technical • medium

Design a dimensional model (Star Schema) for Swiggy's food delivery business. Identify the facts and dimensions.

#Star Schema #Fact Tables #Dimension Tables

Practice

Data Engineer • Technical • medium

How would you handle slowly changing dimensions (SCD Type 2) for a restaurant's menu prices in your data warehouse?

#SCD Type 2 #Data Warehousing #ETL

Practice

Data Engineer • Technical • easy

Explain how you would optimize Amazon S3 storage costs for Swiggy's massive volume of delivery proof images and application logs.

#AWS S3 #Cost Optimization #Lifecycle Policies

Practice

Data Engineer • Technical • easy

How do you securely manage database credentials and API keys in your data pipelines?

#Secret Management #AWS Secrets Manager #Airflow Connections

Practice

Data Engineer • Technical • hard

Write a SQL query to find the percentage of users who placed a second order within 7 days of their first order.

#Cohort Analysis #Self Joins #Window Functions

Practice

Data Engineer • Technical • medium

How do you ensure data quality and validate data before it is consumed by downstream machine learning models for Swiggy's recommendation engine?

#Data Validation #Great Expectations #Anomaly Detection

Practice

Data Engineer • Technical • hard

Given an orders table, write a SQL query to calculate the 7-day rolling average of order values for each user.

#Window Functions #Time Series #Moving Averages

Practice

Data Engineer • Technical • hard

Write a query to find delivery partners who have delivered more than 5 orders consecutively without any cancellations.

#Gaps and Islands #Window Functions #Conditional Logic

Practice

Data Scientist • Behavioral • medium

Tell me about a time you had to push back on a product manager's request because the data didn't support it.

#Communication #Stakeholder Management #Data-Driven Decision Making

Practice

Data Scientist • Behavioral • easy

Tell me about a time you had to explain a complex machine learning concept to a non-technical stakeholder.

#Communication #Storytelling #Business Acumen

Practice

Data Scientist • Behavioral • medium

Describe a situation where your deployed ML model's performance degraded over time. How did you detect and fix it?

#MLOps #Model Drift #Monitoring #Problem Solving

Practice

Data Scientist • Behavioral • medium

Tell me about a time you had to work with a highly imbalanced dataset. What techniques did you use and why?

#Imbalanced Data #SMOTE #Class Weights #Evaluation Metrics

Practice

Data Scientist • Behavioral • medium

Describe a time you took the initiative to optimize an existing process or model without being asked.

#Proactivity #Impact #Continuous Improvement

Practice

Data Scientist • Coding • medium

Given an array of integers representing order delivery times, write a function to find the longest contiguous subarray with an average delivery time below a given threshold.

#Sliding Window #Arrays #Prefix Sum

Practice

Data Scientist • Coding • easy

Write a Python function to calculate the Haversine distance between two GPS coordinates (restaurant and customer).

#Math #Geospatial #Python

Practice

Data Scientist • Coding • hard

Write a SQL query to calculate the median order value for each user segment (e.g., Swiggy One vs. Non-Swiggy One).

#Percentiles #Window Functions #Advanced SQL

Practice

Data Scientist • Coding • easy

Write a Python script to parse a large JSON log file of user clicks and return the top 5 most frequently clicked restaurant IDs.

#Data Parsing #Hash Maps #Heaps #Python

Practice

Data Scientist • Coding • hard

Write a SQL query to calculate the week-over-week retention rate of new users who joined in Q1.

#Cohort Analysis #Self Joins #Date Manipulation

Practice

Data Scientist • Coding • medium

Write a SQL query to find the top 3 restaurants in each city based on the number of completed orders in the last 30 days.

#Window Functions #Aggregations #Date Functions

Practice

Data Scientist • Coding • medium

Write a SQL query to find delivery executives who have a cancellation rate of more than 5% but have completed at least 100 orders.

#Filtering #Aggregations #Having Clause

Practice

Data Scientist • Coding • hard

Given a dataset of delivery coordinates, write an algorithm to find the optimal route for a delivery executive carrying batched orders.

#Graph Theory #Traveling Salesperson Problem #Heuristics #Dynamic Programming

Practice

Data Scientist • Coding • medium

Write a Python function to find the maximum overlapping active orders given a list of order start and end times.

#Sorting #Intervals #Sweep Line Algorithm

Practice

Data Scientist • System Design • hard

Design an ETA (Estimated Time of Arrival) prediction system for Swiggy food delivery.

#Machine Learning Architecture #Real-time Systems #Regression #Feature Engineering

Practice

Data Scientist • System Design • hard

How would you design a dynamic surge pricing model during peak hours or bad weather?

#Dynamic Pricing #Supply and Demand #Optimization #Reinforcement Learning

Practice

Data Scientist • System Design • medium

Explain how you would build a recommendation engine for Swiggy Instamart to cross-sell items during checkout.

#Recommender Systems #Collaborative Filtering #Market Basket Analysis #Deep Learning

Practice

Data Scientist • System Design • medium

Design a machine learning model to detect promo code abuse by users creating multiple accounts.

#Fraud Detection #Anomaly Detection #Graph Neural Networks #Classification

Practice

Data Scientist • System Design • hard

How would you build a search ranking algorithm for restaurants when a user searches for a generic term like 'Biryani'?

#Information Retrieval #Learning to Rank #Personalization #NLP

Practice

Data Scientist • System Design • medium

Design a system to automatically classify customer support chat tickets into categories (e.g., refund, delayed order, missing item).

#Text Classification #NLP #LLMs #System Architecture

Practice

Data Scientist • System Design • hard

Design a system to predict whether an ongoing order will be delayed, so proactive communication can be sent to the customer.

#Streaming Data #Event-driven Architecture #Classification #Kafka

Practice

Data Scientist • System Design • medium

Design an ML pipeline to identify and remove duplicate restaurant listings created by partners trying to game the system.

#Entity Resolution #Fuzzy Matching #Embeddings #Clustering

Practice

Data Scientist • System Design • hard

Design a system to suggest autocomplete queries as a user types in the Swiggy search bar, considering their past order history.

#Trie Data Structure #Caching #Personalization #Low Latency

Practice

Data Scientist • Technical • medium

What metrics would you track to evaluate the success of a new personalized homepage feed on the Swiggy app?

#Product Metrics #A/B Testing #User Engagement

Practice

Data Scientist • Technical • medium

Explain the mathematical difference between XGBoost and Random Forest. Why might one perform better for ETA prediction?

#Ensemble Methods #Gradient Boosting #Decision Trees #Bias-Variance Tradeoff

Practice

Data Scientist • Technical • medium

What loss function would you use for a model predicting the exact preparation time of food at a restaurant, and why?

#Loss Functions #Regression #Asymmetric Loss

Practice

Data Scientist • Technical • hard

How would you use causal inference to determine if a recent discount campaign actually drove incremental orders or just subsidized existing demand?

#Causal Inference #Difference-in-Differences #Propensity Score Matching #Incrementality

Practice

Data Scientist • Technical • medium

Explain how you would use NLP to extract and categorize menu items from raw text or images of physical menus.

#NLP #OCR #Named Entity Recognition #Transformers

Practice

Data Scientist • Technical • hard

How do you handle network effects and interference when running an A/B test on a new delivery batching algorithm?

#A/B Testing #Experimentation #Network Effects #Causal Inference

Practice

Data Scientist • Technical • medium

How would you model the probability of a delivery partner accepting an order assignment?

#Classification #Logistic Regression #Feature Engineering #Behavioral Modeling

Practice

Data Scientist • Technical • hard

How would you forecast the daily inventory requirement for perishable goods in a Swiggy Instamart dark store?

#Time Series Forecasting #ARIMA #Prophet #Deep Learning

Practice

Data Scientist • Technical • hard

Explain the concept of Multi-Armed Bandits. How could Swiggy use this for optimizing banner ads on the app homepage?

#Reinforcement Learning #Multi-Armed Bandits #Exploration vs Exploitation

Practice

Data Scientist • Technical • medium

How do you address the cold start problem for a newly onboarded restaurant in our recommendation system?

#Recommender Systems #Cold Start #Content-based Filtering #Heuristics

Practice

Data Scientist • Technical • hard

How would you evaluate the trade-off between delivery speed and batching efficiency (combining multiple orders)?

#Optimization #Trade-off Analysis #Simulation #Business Metrics

Practice

Data Scientist • Technical • medium

How would you handle missing or noisy GPS pings from delivery executives' phones when calculating historical travel times?

#Data Cleaning #Imputation #Geospatial Analysis #Kalman Filters

Practice

DevOps Engineer • Behavioral • medium

Tell me about a time you caused a Sev-1 production outage. How did you handle the immediate mitigation, and what was the outcome of the post-mortem?

#Incident Management #Post-mortem #Ownership

Practice

DevOps Engineer • Behavioral • medium

Describe a situation where a development team wanted to push a critical feature to production on a Friday evening, but it lacked proper monitoring and alerts. How did you handle it?

#Stakeholder Management #Pushback #Production Readiness

Practice

DevOps Engineer • Behavioral • hard

Tell me about a time you had to collaborate with multiple engineering squads to migrate a legacy system to a new infrastructure platform with zero downtime.

#Collaboration #Migration #Project Management

Practice

DevOps Engineer • Behavioral • medium

How do you balance the need to deliver infrastructure for new product features (like Swiggy Dineout) versus paying down existing technical debt?

#Prioritization #Technical Debt #Agile

Practice

DevOps Engineer • Coding • easy

Write a simple Go program that exposes a /health HTTP endpoint and checks the connectivity to a PostgreSQL database, returning 200 OK or 503 Service Unavailable.

#Golang #API #Database Connectivity

Practice

DevOps Engineer • Coding • medium

Write a Python script to parse a 50GB Nginx access log file, find the top 10 IP addresses with the most 5xx errors, and output them in JSON format.

#Python #Log Parsing #Data Structures #Memory Management

Practice

DevOps Engineer • Coding • medium

Write a Python script using Boto3 to find and delete all unattached EBS volumes older than 30 days across all AWS regions.

#Python #Boto3 #AWS #Automation

Practice

DevOps Engineer • Coding • medium

Write a Bash script to find all pods in a specific Kubernetes namespace that have been in a 'CrashLoopBackOff' state for more than 10 minutes and restart them.

#Bash #kubectl #Automation

Practice

DevOps Engineer • System Design • hard

Design an automated disaster recovery and failover mechanism for Swiggy's primary relational database (Amazon Aurora) across multiple AWS regions.

#Disaster Recovery #AWS Aurora #High Availability #RPO/RTO

Practice

DevOps Engineer • System Design • medium

Design the CDN and edge caching strategy for Swiggy's static assets (restaurant images, app icons) to ensure sub-50ms latency for users across India.

#CDN #AWS CloudFront #Caching #Edge Computing

Practice

DevOps Engineer • System Design • hard

Design a centralized logging and monitoring system for Swiggy's 500+ microservices generating terabytes of logs daily.

#ELK/EFK #Prometheus #Grafana #Distributed Tracing

Practice

DevOps Engineer • System Design • hard

How would you design the Kubernetes cluster architecture to handle Swiggy's New Year's Eve traffic spike where load increases by 10x in minutes?

#Kubernetes #Autoscaling #AWS EKS #Capacity Planning

Practice

DevOps Engineer • System Design • hard

Swiggy wants to build an Internal Developer Platform (IDP) to allow developers to self-serve infrastructure. How would you design the architecture using tools like Backstage, Terraform, and ArgoCD?

#Platform Engineering #Backstage #Self-Service #GitOps

Practice

DevOps Engineer • System Design • hard

Design a scalable CI/CD pipeline for a monorepo containing 50 microservices, ensuring that only the modified services are built and deployed.

#Monorepo #Jenkins/GitLab CI #Build Optimization

Practice

DevOps Engineer • Technical • medium

What are Helm hooks? Give an example of how you would use a pre-install hook for a database migration job during a microservice deployment.

#Helm #Deployments #Database Migrations

Practice

DevOps Engineer • Technical • easy

Explain the difference between a PersistentVolume (PV), PersistentVolumeClaim (PVC), and StorageClass. How does dynamic provisioning work in AWS EKS?

#Kubernetes Storage #AWS EBS #CSI Drivers

Practice

DevOps Engineer • Technical • medium

A developer accidentally committed a file containing AWS access keys to the main branch and pushed it. Walk me through the exact steps to remediate this security breach.

#Git #Security Incident #AWS IAM

Practice

DevOps Engineer • Technical • medium

How would you configure Nginx to rate-limit incoming requests to the Swiggy login API to prevent brute-force attacks?

#Nginx #Security #Rate Limiting

Practice

DevOps Engineer • Technical • medium

Explain the concept of IAM Roles for Service Accounts (IRSA) in EKS. Why is it preferred over attaching IAM roles to the underlying EC2 worker nodes?

#AWS IAM #Kubernetes Security #EKS

Practice

DevOps Engineer • Technical • medium

A production server is reporting 'No space left on device', but when you run df -h, it shows 40% free space. What is the likely cause and how do you fix it?

#Linux #Filesystems #Troubleshooting

Practice

DevOps Engineer • Technical • hard

Explain how Prometheus pulls metrics. How would you design the Prometheus architecture to scrape metrics from 10,000 ephemeral pods without overwhelming the Prometheus server?

#Prometheus #Monitoring #Architecture #Thanos/Cortex

Practice

DevOps Engineer • Technical • hard

Swiggy's restaurant menu API relies heavily on Redis. If the Redis cluster experiences a sudden memory eviction issue, how do you troubleshoot and resolve it?

#Redis #Caching #Troubleshooting #Memory Management

Practice

DevOps Engineer • Technical • medium

How do you structure Terraform code for multiple environments (dev, staging, prod) to ensure DRY principles?

#Terraform #Code Architecture #Modules #Terragrunt

Practice

DevOps Engineer • Technical • medium

We have a batch processing job for Swiggy Instamart inventory that requires high memory. How do you ensure these pods are only scheduled on specific memory-optimized nodes using Taints, Tolerations, and Node Affinity?

#Kubernetes Scheduling #Taints and Tolerations #Node Affinity

Practice

DevOps Engineer • Technical • medium

Explain what happens at the OS and network level when a user types swiggy.com into their browser, focusing on DNS resolution and TCP handshake.

#DNS #TCP/IP #OSI Model

Practice

DevOps Engineer • Technical • medium

How would you optimize a Dockerfile for a Node.js application to minimize the image size and build time, considering it's deployed hundreds of times a day?

#Docker #Optimization #Node.js

Practice

DevOps Engineer • Technical • medium

How do you inject secrets securely into a Jenkins pipeline and subsequently into a Kubernetes pod without exposing them in the source code or environment variables?

#Secret Management #HashiCorp Vault #Kubernetes #Jenkins

Practice

DevOps Engineer • Technical • medium

How would you securely connect a Swiggy VPC in the ap-south-1 region to a third-party payment gateway's VPC without traversing the public internet?

#AWS Networking #VPC Peering #Transit Gateway #PrivateLink

Practice

DevOps Engineer • Technical • hard

Swiggy uses Kafka heavily for order state transitions. How do you monitor Kafka consumer lag, and how would you automate the scaling of consumer pods based on this lag?

#Kafka #KEDA #Kubernetes Autoscaling

Practice

DevOps Engineer • Technical • easy

Explain the difference between ClusterIP, NodePort, and LoadBalancer in Kubernetes. Which one would you use for an internal gRPC service at Swiggy and why?

#Networking #Kubernetes Services #gRPC

Practice

DevOps Engineer • Technical • medium

A Swiggy checkout microservice running on an EC2 instance is suddenly experiencing high CPU utilization (99%). Walk me through your exact troubleshooting steps.

#Troubleshooting #Linux #Performance Tuning

Practice

DevOps Engineer • Technical • medium

We use Terraform to manage our AWS infrastructure. How do you handle Terraform state file locking and what happens if the state file gets corrupted?

#Terraform #State Management #AWS S3 #DynamoDB

Practice

DevOps Engineer • Technical • hard

Explain how you would implement a zero-downtime Canary deployment for the Swiggy Delivery Partner tracking microservice using ArgoCD and Istio.

#ArgoCD #Istio #GitOps #Deployment Strategies

Practice

DevOps Engineer • Technical • medium

Swiggy's AWS bill is growing rapidly due to EC2 and NAT Gateway costs. How would you audit and optimize this without impacting production availability?

#FinOps #AWS #Cost Optimization #Networking

Practice

DevOps Engineer • Technical • easy

How do you handle sensitive data like database passwords in Ansible playbooks? Explain how Ansible Vault works.

#Ansible #Security #Secret Management

Practice

Frontend Engineer • Behavioral • medium

Describe a situation where you had to debug a critical production issue on the frontend (e.g., a blank screen on checkout). What was your approach?

#Debugging #Incident Management #Root Cause Analysis

Practice

Frontend Engineer • Behavioral • medium

Tell me about a time you mentored a junior engineer or helped level up your team's frontend practices.

#Mentorship #Code Reviews #Team Building

Practice

Frontend Engineer • Behavioral • medium

Tell me about a time you had to push back on a Product Manager's requirement because of technical constraints or tight deadlines.

#Communication #Stakeholder Management #Prioritization

Practice

Frontend Engineer • Coding • medium

Create a custom React hook `useDebounce` and demonstrate how you would use it for a Swiggy restaurant search input to minimize API calls.

#Custom Hooks #Debouncing #Performance Optimization

Practice

Frontend Engineer • Coding • medium

Write a JavaScript function to flatten a deeply nested object. Keys should be concatenated with a dot (e.g., `user.address.city`).

#Recursion #Object Manipulation #Data Structures

Practice

Frontend Engineer • Coding • hard

Machine Coding: Build an autocomplete search bar for restaurants. It must include caching for previously searched terms and keyboard navigation (up/down arrows to select).

#React #Caching #Keyboard Accessibility #Debouncing

Practice

Frontend Engineer • Coding • hard

Write a function to deeply clone a JavaScript object. Ensure it handles circular references, Dates, and Arrays correctly.

#Recursion #Memory Management #Object Manipulation

Practice

Frontend Engineer • Coding • hard

Machine Coding: Build a nested comment system similar to Reddit or Swiggy restaurant reviews. It should support N-level deep replies, adding new comments, and deleting comments.

#React #Recursion #State Management #DOM Manipulation

Practice

Frontend Engineer • Coding • hard

Machine Coding: Implement a multi-step form for a restaurant onboarding portal (Swiggy Partner). It should have validation, state persistence across steps, and a final review page.

#React #Forms #State Management #Validation

Practice

Frontend Engineer • Coding • easy

Machine Coding: Implement a 5-star rating component. It should support hover effects (highlighting stars up to the cursor) and allow fractional ratings (e.g., 4.5 stars).

#React #CSS #Event Handling

Practice

Frontend Engineer • Coding • medium

Implement an LRU (Least Recently Used) Cache in JavaScript. It should have `get(key)` and `put(key, value)` methods, both operating in O(1) time complexity.

#Data Structures #Map #Linked List

Practice

Frontend Engineer • Coding • medium

Write a polyfill for `Function.prototype.bind`.

#Polyfills #this keyword #Closures #Arguments

Practice

Frontend Engineer • Coding • medium

Given an array of overlapping intervals representing a restaurant's operating hours, write a function to merge all overlapping intervals.

#Arrays #Sorting #Logic

Practice

Frontend Engineer • Coding • medium

Implement an Event Emitter class in JavaScript with `on`, `off`, `emit`, and `once` methods.

#Design Patterns #Pub/Sub #Classes

Practice

Frontend Engineer • Coding • medium

Machine Coding: Build an infinite scrolling list for the Swiggy restaurant feed. It should fetch more data as the user scrolls near the bottom.

#React #Intersection Observer #Pagination #API Integration

Practice

Frontend Engineer • Coding • medium

Implement a polyfill for Promise.all(). How would you handle a scenario where one of the promises rejects?

#Promises #Asynchronous JavaScript #Polyfills

Practice

Frontend Engineer • Coding • medium

Implement a generic Carousel component in React. It should support auto-play, infinite looping, and touch/swipe gestures for mobile users.

#React #CSS Transitions #Touch Events #Component Design

Practice

Frontend Engineer • Coding • medium

Write a function to check if two DOM trees are structurally identical and have the same attributes and text content.

#DOM #Recursion #Tree Traversal

Practice

Frontend Engineer • Coding • medium

Write a function to find the length of the longest substring without repeating characters in a given string.

#Strings #Sliding Window #Hash Map

Practice

Frontend Engineer • System Design • medium

How would you implement internationalization (i18n) and localization in a large-scale React app to support multiple Indian languages?

#i18n #Localization #Asset Management #React Context

Practice

Frontend Engineer • System Design • medium

Design a scalable frontend logging and error tracking system for the Swiggy consumer web app. How do you ensure it doesn't impact app performance?

#Error Boundaries #Beacon API #Batching #Observability

Practice

Frontend Engineer • System Design • hard

Design the Swiggy Live Order Tracking screen. How do you handle real-time delivery partner location updates, map rendering, and battery/network efficiency on the web?

#Maps Integration #WebSockets #Polling #Performance

Practice

Frontend Engineer • System Design • medium

Design a notification center for the Swiggy app that handles incoming push notifications, in-app alerts, and read/unread states across multiple tabs.

#Service Workers #Broadcast Channel API #State Synchronization

Practice

Frontend Engineer • System Design • hard

Design the frontend architecture for Swiggy Instamart's live inventory and cart system. How do you handle scenarios where an item goes out of stock while it is in the user's cart?

#WebSockets #State Synchronization #Concurrency #UI/UX

Practice

Frontend Engineer • System Design • medium

How would you optimize the performance of the Swiggy home page, which contains hundreds of restaurant images, carousels, and dynamic offers?

#Lazy Loading #CDN #Core Web Vitals #Virtualization

Practice

Frontend Engineer • System Design • hard

Design the checkout page for Swiggy. How do you handle payment gateway integrations, coupon applications, and state recovery if the payment fails?

#State Management #Security #Resilience #Third-party Integration

Practice

Frontend Engineer • Technical • medium

Discuss the pros and cons of Server-Side Rendering (SSR) vs Client-Side Rendering (CSR). Why might Swiggy choose Next.js for its SEO-facing pages?

#SSR #CSR #Next.js #SEO

Practice

Frontend Engineer • Technical • medium

Explain the Event Loop in JavaScript. What is the difference between the microtask queue and the macrotask queue? Give an example of each.

#Event Loop #Concurrency Model #V8 Engine

Practice

Frontend Engineer • Technical • hard

What is React Fiber? How does it improve rendering performance compared to the older Stack Reconciler?

#React Internals #Reconciliation #Rendering

Practice

Frontend Engineer • Technical • easy

Explain the CSS Box Model. What is the difference between `box-sizing: border-box` and `box-sizing: content-box`?

#CSS #Layouts #Box Model

Practice

Frontend Engineer • Technical • medium

How does Redux work under the hood? Explain the difference between Redux Thunk and Redux Saga for handling side effects.

#Redux #Middleware #Generators #Side Effects

Practice

Frontend Engineer • Technical • medium

What are Service Workers? How would you use them to make the Swiggy web app work offline or load faster on slow networks?

#PWA #Service Workers #Caching Strategies #Offline

Practice

Frontend Engineer • Technical • easy

Explain the concept of closures in JavaScript. Provide a practical use case where closures are essential.

#Closures #Scope #Memory

Practice

Frontend Engineer • Technical • medium

How do you prevent unnecessary re-renders in a React application? Discuss `React.memo`, `useMemo`, and `useCallback`.

#Performance #Hooks #Re-rendering

Practice

Frontend Engineer • Technical • medium

What is Webpack? Explain how tree shaking works and how you would configure a project to ensure optimal bundle sizes.

#Webpack #Bundling #Tree Shaking #Performance

Practice

Machine Learning Engineer • Behavioral • hard

Tell me about a time you optimized an existing ML pipeline to save cloud costs or significantly reduce inference latency.

#Engineering Excellence #Cost Optimization #Latency #System Architecture

Practice

Machine Learning Engineer • Behavioral • medium

Describe a situation where you had to explain a complex ML model's decisions to non-technical stakeholders, like City Operations Managers.

#Communication #Empathy #Cross-functional #Explainable AI

Practice

Machine Learning Engineer • Behavioral • medium

At Swiggy, Product Managers often request multiple ML features simultaneously. How do you prioritize which model to build first?

#Stakeholder Management #Agile #Product Sense #Prioritization

Practice

Machine Learning Engineer • Behavioral • medium

Tell me about a time a machine learning model you deployed failed or degraded in production. How did you identify the issue and resolve it?

#Ownership #Post-mortems #Problem Solving #Incident Management

Practice

Machine Learning Engineer • Behavioral • easy

Why do you want to join Swiggy? What specific challenges in the food delivery or quick commerce space excite you from an ML perspective?

#Domain Interest #Motivation #Company Knowledge

Practice

Machine Learning Engineer • Coding • medium

Implement the K-Means clustering algorithm from scratch in Python using NumPy. Do not use scikit-learn.

#Machine Learning Algorithms #Python #Math #NumPy

Practice

Machine Learning Engineer • Coding • medium

Given a delivery bag with a maximum weight capacity W, and a list of orders with specific weights and delivery payouts, write a function to maximize the payout.

#Dynamic Programming #Optimization #Knapsack

Practice

Machine Learning Engineer • Coding • medium

Given an 'orders' table, write a SQL query to find the top 3 most ordered dishes per city in the last 30 days.

#Window Functions #Aggregation #Joins

Practice

Machine Learning Engineer • Coding • hard

A delivery partner needs to pick up orders from 2 restaurants and deliver them to 2 customers. Write an algorithm to find the shortest valid route (pickups must precede respective drop-offs).

#Graphs #Shortest Path #Backtracking #TSP

Practice

Machine Learning Engineer • Coding • medium

Implement a Trie data structure to support search autocomplete for Swiggy Instamart items. It should support insert, search, and return top 3 matching prefixes.

#Trees #String Manipulation #Tries #Design

Practice

Machine Learning Engineer • Coding • medium

Write a Python function to compute the NDCG@K given a list of predicted scores and a list of true relevance labels.

#Python #Array Manipulation #Math

Practice

Machine Learning Engineer • Coding • medium

Write a SQL query to calculate the 7-day rolling average of delivery times for each delivery zone.

#Window Functions #Date Functions #Time Series

Practice

Machine Learning Engineer • Coding • medium

Given a list of active time intervals for a delivery executive (e.g., [[10, 12], [11, 15], [16, 18]]), write a function to merge overlapping intervals to calculate total active hours.

#Arrays #Sorting #Intervals

Practice

Machine Learning Engineer • Coding • easy

Write a Python script using Pandas to perform stratified sampling on a dataset of 10 million Swiggy orders, stratified by 'city_id'.

#Python #Pandas #Data Processing

Practice

Machine Learning Engineer • System Design • hard

Design a personalized restaurant recommendation system for the Swiggy homepage. How do you balance relevance, novelty, and business metrics like delivery cost?

#Recommender Systems #Collaborative Filtering #Two-Tower Models #Ranking

Practice

Machine Learning Engineer • System Design • hard

Design a demand forecasting system for Swiggy Instamart dark stores to predict inventory requirements for the next 7 days.

#Time Series Forecasting #Supply Chain #Demand Prediction #Deep Learning

Practice

Machine Learning Engineer • System Design • medium

Design an intent classification model for Swiggy's customer support chatbot. How do you handle out-of-domain queries and multi-lingual text?

#NLP #Classification #Real-time Inference #Chatbots

Practice

Machine Learning Engineer • System Design • medium

Design a system to predict Delivery Partner churn. How would you define 'churn' for gig workers who don't have formal contracts?

#Survival Analysis #Classification #Churn Prediction #Feature Engineering

Practice

Machine Learning Engineer • System Design • medium

How would you design a model to predict the exact food preparation time for a specific dish at a specific restaurant?

#Time Series #Regression #Feature Engineering

Practice

Machine Learning Engineer • System Design • medium

Design a machine learning system to detect promo-code abuse and fraudulent orders in real-time.

#Anomaly Detection #Classification #Graph ML #Real-time Inference

Practice

Machine Learning Engineer • System Design • hard

How would you design a dynamic 'surge pricing' model for Swiggy delivery during peak hours or bad weather conditions?

#Dynamic Pricing #Elasticity #Regression #Marketplace Matching

Practice

Machine Learning Engineer • System Design • hard

Design Swiggy's ETA (Estimated Time of Arrival) prediction system from scratch. How would you account for food preparation time, delivery partner assignment, and real-time traffic?

#ML System Design #Regression #Real-time Systems #Geospatial Data

Practice

Machine Learning Engineer • Technical • medium

Why is XGBoost often preferred over Random Forest for tabular data tasks like ETA prediction? Explain the mathematical difference in how they build trees.

#Tree Models #Ensemble Methods #Gradient Boosting

Practice

Machine Learning Engineer • Technical • medium

Explain the difference between pointwise, pairwise, and listwise learning to rank. Which approach would you use for Swiggy's dish search, and why?

#Learning to Rank #Information Retrieval #NLP

Practice

Machine Learning Engineer • Technical • medium

How do you handle the cold start problem for a newly onboarded restaurant on Swiggy that has no historical order data?

#Recommender Systems #Cold Start #Content-based Filtering #Heuristics

Practice

Machine Learning Engineer • Technical • easy

What is the difference between NDCG and MAP? In what scenario would you prefer one over the other for evaluating search results?

#Evaluation Metrics #Recommender Systems #Search

Practice

Machine Learning Engineer • Technical • medium

How do you detect and handle data drift in a production ML model, such as our ETA prediction model during a sudden lockdown?

#Model Monitoring #Concept Drift #Statistical Tests

Practice

Machine Learning Engineer • Technical • medium

If an offline recommendation model shows a 10% improvement in NDCG, but the online A/B test shows a drop in conversion rate, what could be the reasons?

#A/B Testing #Evaluation Metrics #Offline-Online Discrepancy

Practice

Machine Learning Engineer • Technical • easy

In our fraud detection dataset, only 0.1% of transactions are fraudulent. How do you train a robust model on this highly imbalanced data?

#Classification #Imbalanced Data #Loss Functions

Practice

Machine Learning Engineer • Technical • hard

Explain the architecture of a Two-Tower neural network. How would you use it to match users to restaurants, and how do you serve it efficiently at scale?

#Neural Networks #Embeddings #Retrieval #Vector Databases

Practice

Machine Learning Engineer • Technical • hard

How would you build an ML pipeline to map millions of unstructured menu items from different restaurants into a standardized Swiggy dish taxonomy?

#Clustering #Embeddings #LLMs #Text Classification

Practice

Machine Learning Engineer • Technical • hard

You have trained a heavy PyTorch model for image quality assessment of restaurant food photos. How do you optimize it for low-latency inference on AWS?

#Model Quantization #ONNX #TensorRT #Caching #Model Serving

Practice

Machine Learning Engineer • Technical • medium

What is the difference between AUC-ROC and PR-AUC? Why is PR-AUC generally preferred for evaluating models on highly skewed datasets?

#Evaluation Metrics #Probability #Imbalanced Data

Practice

Machine Learning Engineer • Technical • medium

Explain Matrix Factorization in the context of collaborative filtering. What are its main limitations when applied to a fast-changing catalog like Swiggy Instamart?

#Recommender Systems #Linear Algebra #ALS #Collaborative Filtering

Practice

Machine Learning Engineer • Technical • hard

How would you use Graph Neural Networks (GNNs) to improve the routing efficiency of delivery partners in a complex road network?

#GNNs #Spatial Data #Routing #Advanced ML

Practice

Software Engineer • Behavioral • medium

Tell me about a time you had to push back on a product manager's unrealistic deadline. How did you negotiate the scope?

#Communication #Conflict Resolution #Agile

Practice

Software Engineer • Behavioral • medium

Describe a situation where a system you built or maintained failed in production. What was the root cause and how did you resolve it?

#Incident Management #Accountability #Problem Solving

Practice

Software Engineer • Behavioral • medium

How do you balance the need to deliver new product features with the necessity of paying down technical debt?

#Prioritization #Technical Debt #Engineering Excellence

Practice

Software Engineer • Behavioral • easy

Tell me about a time you mentored a junior engineer or helped a peer overcome a technical roadblock.

#Mentorship #Teamwork #Empathy

Practice

Software Engineer • Behavioral • easy

Why do you want to join Swiggy? What specific engineering challenges in the food delivery or quick commerce space excite you?

#Motivation #Domain Knowledge #Company Fit

Practice

Software Engineer • Coding • medium

Given a grid representing an Instamart warehouse where 0 is empty, 1 is fresh produce, and 2 is rotten produce, find the minimum minutes until all produce rots.

#Graphs #Breadth-First Search #Matrix

Practice

Software Engineer • Coding • hard

Design a data structure to find the top K trending dishes in a specific geohash in real-time from a continuous stream of orders.

#Heaps #Hash Table #Stream Processing

Practice

Software Engineer • Coding • medium

Find the maximum number of active orders in any sliding window of 'W' minutes given a stream of order timestamps.

#Sliding Window #Queues #Two Pointers

Practice

Software Engineer • Coding • hard

Implement a trie-based autocomplete system for searching restaurant names and dishes that returns the top 3 matches based on historical search frequency.

#Trie #Design #Strings

Practice

Software Engineer • Coding • medium

Find the K closest delivery executives to a restaurant given an array of their [x, y] coordinates and the restaurant's location.

#Heaps #Geometry #Sorting

Practice

Software Engineer • Coding • hard

Write a program to assign N orders to M delivery executives such that the total wait time is minimized.

#Dynamic Programming #Bipartite Matching #Graphs

Practice

Software Engineer • Coding • medium

Given an array of delivery intervals [start, end], merge all overlapping delivery windows to find the continuous busy periods for a delivery executive.

#Arrays #Sorting #Intervals

Practice

Software Engineer • Coding • medium

Given a matrix of 1s (serviceable areas) and 0s (unserviceable areas), find the number of distinct delivery zones (islands).

#Graphs #Depth-First Search #Matrix

Practice

Software Engineer • Coding • hard

Calculate the minimum time required to deliver an order from a restaurant to a customer considering a city map represented as a weighted graph where edges are traffic delays.

#Graphs #Dijkstra's Algorithm #Shortest Path

Practice

Software Engineer • Coding • medium

Implement an LRU Cache to store the most frequently accessed restaurant menus. It should support get() and put() operations in O(1) time.

#Design #Hash Table #Linked List

Practice

Software Engineer • System Design • medium

Machine Coding: Design a Rating and Review system where users can rate restaurants and delivery partners, and fetch the average rating efficiently.

#Data Modeling #Caching #Low Level Design

Practice

Software Engineer • System Design • hard

Design the delivery executive assignment system. How do you efficiently find the best executive for a new order?

#Geospatial Databases #Quadtrees #Matching Algorithms

Practice

Software Engineer • System Design • medium

Design a notification system that sends SMS, Email, and Push notifications for order status updates with an at-least-once delivery guarantee.

#Pub/Sub #Asynchronous Processing #Retry Mechanisms

Practice

Software Engineer • System Design • hard

Design Swiggy's restaurant search and recommendation engine. How do you handle typos and location-based filtering?

#Elasticsearch #Search #Recommendation Systems

Practice

Software Engineer • System Design • medium

Design a distributed logging and monitoring system for Swiggy's microservices architecture.

#Observability #ELK Stack #Distributed Tracing

Practice

Software Engineer • System Design • hard

Machine Coding: Design the Low-Level Architecture for a Food Delivery App. Implement classes for User, Restaurant, Order, and Cart. Handle state transitions for an Order.

#Object Oriented Design #State Pattern #Low Level Design

Practice

Software Engineer • System Design • hard

Machine Coding: Design an in-memory message queue similar to Kafka with support for topics, publishers, and consumer groups.

#Concurrency #Observer Pattern #Low Level Design

Practice

Software Engineer • System Design • medium

Machine Coding: Design a Promo Code Evaluation Engine. Support different types of discounts (flat, percentage, max cap) and user-specific eligibility rules.

#Strategy Pattern #Extensibility #Low Level Design

Practice

Software Engineer • System Design • medium

Machine Coding: Design a Wallet System where users can add money, pay for orders, and receive refunds. Ensure thread safety for concurrent transactions.

#Concurrency #Transactions #Low Level Design

Practice

Software Engineer • System Design • medium

Design a highly available API Gateway for Swiggy that can handle rate limiting, authentication, and request routing.

#API Gateway #Rate Limiting #Security

Practice

Software Engineer • System Design • hard

Design the inventory management system for Swiggy Instamart. How do you handle high concurrency when 1000 users try to buy the last PS5 during a flash sale?

#Concurrency #Distributed Locks #Database Transactions

Practice

Software Engineer • System Design • hard

Design a surge pricing system that dynamically updates delivery fees based on weather, demand, and fleet availability.

#Stream Processing #Event-Driven Architecture #Scalability

Practice

Software Engineer • System Design • hard

Design Swiggy's real-time order tracking system where customers can see the live location of the delivery executive.

#High Level Design #WebSockets #Kafka #Geospatial

Practice

Software Engineer • Technical • hard

Explain the Saga design pattern. How would you implement distributed transactions across the Order, Payment, and Restaurant microservices?

#Distributed Transactions #Saga Pattern #Event Sourcing

Practice

Software Engineer • Technical • medium

What is the difference between clustered and non-clustered indexes in MySQL? How does the InnoDB engine store them?

#SQL #Indexing #MySQL

Practice

Software Engineer • Technical • medium

How does Kafka guarantee message ordering within a partition, and how would you handle out-of-order messages in a consumer?

#Kafka #Distributed Systems #Messaging

Practice

Software Engineer • Technical • medium

Explain the internal working of ConcurrentHashMap in Java. How does it achieve thread safety without locking the entire map?

#Java #Multithreading #Data Structures

Practice

Software Engineer • Technical • medium

How would you handle a race condition in a relational database when two concurrent transactions attempt to deduct the same inventory count?

#SQL #Transactions #Concurrency Control

Practice

Software Engineer • Technical • hard

Explain the CAP theorem. In the context of Swiggy's cart service, would you prioritize Availability or Consistency, and why?

#CAP Theorem #Distributed Systems #Architecture

Practice

Software Engineer • Technical • medium

How does Garbage Collection work in Java? Which GC would you choose for a low-latency microservice like Swiggy's pricing engine?

#Java #Garbage Collection #Performance Tuning

Practice

Swiggy

The Interview Loop

Recruiter Screen (30 min)

Technical Loop (3-4 Rounds)

Interview Question Bank

Describe a situation where a production deployment caused a major outage. How did you debug, resolve, and prevent it from happening again?

Give an example of a time you went above and beyond to improve the performance, scalability, or reliability of a backend system.

Tell me about a time you had to push back on a product manager's timeline because of technical debt or architectural concerns.

Machine Coding: Design a Splitwise-like application for splitting food bills among friends with exact, percentage, and equal split strategies.

Machine Coding: Implement a cache with an LRU eviction policy and Time-To-Live (TTL) for each key.

Given a grid representing a city map with restaurants, customers, and roadblocks, find the shortest path for a delivery executive to pick up and deliver the food.

Merge K sorted arrays/lists. (Context: Merging timestamped logs from different microservices).

Find the Top K frequent elements in a stream of data (e.g., finding top K trending dishes in a locality).

Given an array of integers representing restaurant ratings over time, find the sliding window maximum of size K.

Find the longest palindromic substring in a given string.

You have a list of delivery executives and a list of orders. Assign orders to executives such that the total distance traveled is minimized.

Given a list of orders with their preparation start and end times, find the maximum number of concurrent orders being prepared at any given time.

Implement a Trie data structure to support fast prefix search for restaurant names.

Machine Coding: Design and implement an in-memory Food Delivery System. It should support adding restaurants, updating menus, placing orders, and assigning the nearest delivery agent.

Machine Coding: Design a Promo Code / Coupon Engine. Support rules like flat discount, percentage discount, maximum cap, and user-specific usage limits.

Design a surge pricing engine for Swiggy that dynamically adjusts delivery fees based on weather, traffic, and real-time demand-supply gaps in specific geohashes.

Design a system to handle Swiggy One memberships, ensuring benefits (like free delivery) are applied correctly at checkout with minimal latency.

Design a location-based service to find the nearest delivery executives for order assignment.

Design a payment processing gateway integration system that handles third-party gateway timeouts and failures gracefully.

Design a highly available notification system to send SMS, Email, and Push notifications for order lifecycle events.

Design Swiggy's cart and checkout service. How do you handle concurrent modifications from multiple devices and out-of-stock scenarios during checkout?

Design a restaurant search and recommendation system that supports typo-tolerance, prefix matching, and personalized ranking.

Design a distributed rate limiter for Swiggy's public APIs to prevent abuse and manage tiered API access.

Design Swiggy Instamart's inventory management system to handle high concurrency during flash sales or peak hours without overselling.

Design Swiggy's real-time delivery tracking system where customers can see the live location of their delivery executive.

What is the CAP theorem and how does it apply to Swiggy's cart service versus its payment service?

How would you handle distributed transactions across the Order, Payment, and Inventory microservices at Swiggy?

Explain how you would optimize a slow-performing SQL query that fetches order history for a user.

Low-Level Design: Design a wallet system where users can add money and pay for orders. Ensure ACID properties are maintained.

How does Kafka ensure exactly-once semantics, and how would you use it for Swiggy's order state machine?

Low-Level Design: Design a distributed task scheduler that can execute tasks at a given time or periodically (similar to Quartz).

Explain the internal working of ConcurrentHashMap in Java and how it differs from Collections.synchronizedMap.

Low-Level Design: Design an elevator system for a multi-story building that optimizes for minimum wait time.

Low-Level Design: Design a thread-safe database connection pool from scratch.

How do you implement distributed locking using Redis to prevent double-booking of a limited Instamart item?

At Swiggy, developers sometimes push back against security policies, asking for full admin access to production to debug faster. How do you handle this pushback?

Describe a project where you significantly reduced cloud infrastructure costs. What was your approach?

Tell me about a time you made a mistake that caused a production outage. How did you handle it, and what did you learn?

Tell me about a time you handled a major production incident. Walk me through your exact steps from the moment the pager went off to the post-mortem.

Write a Bash or Python script to find all unattached EBS volumes in an AWS region and delete them if they have been unattached for more than 7 days.

Write a shell command or short script to parse an Nginx access log file and output the top 10 IP addresses that made the most requests.

Write a Terraform module to provision an S3 bucket that enforces Swiggy's compliance rules: it must be private, encrypted at rest with KMS, and have versioning enabled.

Write a Python script using Boto3 to list all AWS IAM users who have access keys older than 90 days and output them to a CSV file.

Write a Bash or Python script that takes a list of 100 Swiggy API endpoints, checks their HTTP status concurrently, and prints only the ones that return a non-200 status.

Design a CDN and caching strategy to serve millions of restaurant menus and food images with ultra-low latency across India.

Design an auto-scaling strategy for background worker nodes that allocate delivery partners to orders, based on the backlog of orders in an SQS queue.

Design a multi-region active-active architecture on AWS for Swiggy's core order management system to ensure high availability during a regional outage.

Design the cloud infrastructure for Swiggy Instamart's real-time inventory system. It needs to handle high read/write throughput and ensure items aren't oversold.

Design a rate-limiting service at the API Gateway level to protect Swiggy's backend services from abuse or DDoS attacks during New Year's Eve.

Design a monitoring and alerting setup using Prometheus and Grafana to track the latency of Swiggy delivery partner location updates.

Swiggy uses Kafka extensively for event streaming (e.g., order state changes). How do you architect a highly available Kafka cluster across multiple Availability Zones?

For Swiggy's core checkout service, would you recommend a Blue/Green deployment or a Canary deployment? Explain how you would implement your choice in Kubernetes.

An order placed on Swiggy touches 15 different microservices. How do you implement distributed tracing to find out exactly which service is causing a 3-second delay?

Swiggy engineers are complaining about 'alert fatigue' because they receive hundreds of PagerDuty alerts daily that resolve themselves. How do you fix this?

If a new deployment causes a severe memory leak in production, how do you ensure the system automatically rolls back to the previous stable version?

How do you securely manage and inject secrets (like database passwords and API keys) into Kubernetes pods without hardcoding them in Git?

Design a modern GitOps CI/CD pipeline for a Golang microservice at Swiggy using tools like GitLab CI, Docker, and ArgoCD.

A developer pings you saying their Kubernetes pod is stuck in a CrashLoopBackOff state. Walk me through the exact kubectl commands and steps you would use to debug this.

We have multiple AWS accounts for different Swiggy environments (Dev, QA, Prod) and business units. Would you use VPC Peering or AWS Transit Gateway to connect them, and why?

Explain how you would handle a split-brain scenario in a distributed caching system like Redis, which Swiggy uses heavily for session management and menu caching.

Swiggy's AWS bill is growing rapidly. What strategies would you implement to optimize costs for our EC2 and EKS workloads without impacting performance?

How would you implement IAM least privilege for a new Swiggy Instamart microservice running on EKS that needs access to a specific S3 bucket and DynamoDB table?

During an IPL final, Swiggy experiences a massive traffic spike. You notice a sudden surge of 5xx errors on an Application Load Balancer. How do you troubleshoot and resolve this?

How do you manage Terraform state in a multi-developer environment, and what happens if two engineers try to apply changes to Swiggy's infrastructure simultaneously?

Walk me through the strategy you would use to upgrade an Amazon EKS cluster running hundreds of Swiggy microservices with zero downtime.

Explain how you would implement mutual TLS (mTLS) between microservices in a Kubernetes cluster using Istio, and how you would verify it is working.

Several microservices in our EKS cluster are randomly failing to resolve internal DNS names. How do you troubleshoot CoreDNS performance issues?

If we use DynamoDB to store user order history, how would you design the Partition Key and Sort Key to efficiently query a user's last 10 orders?

You notice that an AWS RDS PostgreSQL read replica is experiencing high replication lag, causing stale data on the Swiggy app. How do you troubleshoot this?

How do you secure Swiggy's internal microservices so they can communicate with each other, but cannot be accessed directly from the public internet?

Tell me about a time your pipeline failed in production and caused a data outage or incorrect metrics. What did you do?

Tell me about a time you had to optimize a slow-running data pipeline. What was the root cause and the impact?

Describe a situation where you disagreed with a product manager or data scientist about a data metric definition. How did you resolve it?

Implement a rate limiter using the Token Bucket algorithm to throttle incoming API requests from restaurant POS systems.

Given a list of delivery partner active hours as intervals [start_time, end_time], write a function to merge all overlapping intervals to find the total active duration.