IBM
Global technology and consulting firm with deep roots in enterprise IT and AI.
3 Rounds
~14 Days
Medium
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
Software Engineer
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Behavioral
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medium
Tell me about a time you had to quickly learn a new technology or framework to complete a project on time.
#Adaptability
#Continuous Learning
Software Engineer
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Behavioral
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medium
Describe a situation where you disagreed with a senior engineer or manager on a technical design. How did you handle it and what was the outcome?
#Conflict Resolution
#Communication
#Technical Leadership
Software Engineer
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Behavioral
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medium
IBM values 'dedication to every client's success'. Can you share an example of when you went above and beyond to solve a critical problem for a customer or end-user?
#Customer Focus
#Problem Solving
#Empathy
Software Engineer
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Behavioral
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medium
Tell me about a time you had to work with a large, undocumented legacy codebase. How did you ensure you didn't break existing functionality while adding new features?
#Legacy Code
#Testing
#Risk Management
Software Engineer
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Behavioral
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medium
Describe a time when a project you were working on failed or missed a critical deadline. What went wrong and what did you learn from the experience?
#Accountability
#Resilience
#Retrospectives
Software Engineer
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Behavioral
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easy
How do you prioritize your tasks when you have multiple urgent deadlines competing for your time across different projects?
#Time Management
#Prioritization
#Agile
Software Engineer
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Behavioral
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medium
Tell me about a time you proactively identified a security vulnerability or a severe performance bottleneck in your team's application. What steps did you take?
#Proactivity
#Security
#Performance
Software Engineer
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Behavioral
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medium
Describe your experience working in a geographically distributed Agile team. How do you handle communication barriers and time zone differences?
#Remote Work
#Communication
#Agile
Software Engineer
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Behavioral
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easy
Why do you want to work for IBM, and how do you see technologies like Hybrid Cloud and AI shaping the future of enterprise software?
#Company Knowledge
#Industry Trends
#Motivation
Software Engineer
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Coding
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easy
Given an array of integers and an integer target, return indices of the two numbers such that they add up to target. Assume exactly one solution exists.
#Arrays
#Hash Table
Software Engineer
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Coding
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easy
Given a string containing just the characters '(', ')', '{', '}', '[' and ']', determine if the input string is valid.
#Strings
#Stack
Software Engineer
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Coding
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medium
Given an array of intervals representing server downtime, merge all overlapping intervals and return an array of the non-overlapping intervals.
#Arrays
#Sorting
Software Engineer
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Coding
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medium
Design and implement a data structure for a Least Recently Used (LRU) cache. It should support get and put operations in O(1) time complexity.
#Hash Table
#Doubly Linked List
#Design
Software Engineer
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Coding
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medium
Given an m x n 2D binary grid representing a map of '1's (land) and '0's (water), return the number of islands. An island is surrounded by water and formed by connecting adjacent lands horizontally or vertically.
#Graph
#DFS
#BFS
Software Engineer
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Coding
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medium
There are a total of numCourses courses you have to take. You are given an array prerequisites where prerequisites[i] = [a_i, b_i] indicates that you must take course b_i first if you want to take course a_i. Return true if you can finish all courses.
#Graph
#Topological Sort
#Cycle Detection
Software Engineer
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Coding
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hard
Given a network of IBM Cloud data centers represented as nodes and the cost to lay fiber optic cables between them as weighted edges, find the minimum cost to connect all data centers.
#Graph
#Minimum Spanning Tree
#Union Find
Software Engineer
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Coding
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easy
Given the head of a singly linked list, reverse the list, and return the reversed list.
#Linked List
#Pointers
Software Engineer
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Coding
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medium
Given a string representing a stream of log characters, find the length of the longest substring without repeating characters.
#Strings
#Sliding Window
#Hash Table
Software Engineer
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Coding
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hard
Given two words, beginWord and endWord, and a dictionary wordList, return the number of words in the shortest transformation sequence from beginWord to endWord.
#Graph
#BFS
#Strings
Software Engineer
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Coding
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medium
Design a stack that supports push, pop, top, and retrieving the minimum element in constant time.
#Stack
#Design
Software Engineer
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Coding
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easy
Given a string of lowercase English letters, find the first non-repeating character in it and return its index. If it does not exist, return -1.
#Strings
#Hash Table
#Counting
Software Engineer
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System Design
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hard
Design a highly available hybrid cloud storage service that synchronizes on-premise enterprise data with IBM Cloud Object Storage.
#Hybrid Cloud
#Data Synchronization
#High Availability
#Storage
Software Engineer
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System Design
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medium
Design a distributed rate limiter for an enterprise API gateway to prevent abuse and enforce client-specific quotas.
#Rate Limiting
#API Gateway
#Redis
Software Engineer
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System Design
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hard
Design a scalable log aggregation system (similar to Splunk or the ELK stack) that can ingest, index, and query terabytes of logs daily from thousands of IBM microservices.
#Log Aggregation
#Kafka
#Elasticsearch
#Big Data
Software Engineer
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System Design
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medium
Design a real-time AI inference pipeline that takes user text, processes it via Watson NLP models, and returns sentiment analysis to a web client.
#AI/ML Pipelines
#WebSockets
#Microservices
#Load Balancing
Software Engineer
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System Design
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hard
Design a distributed message queue system similar to Apache Kafka or IBM MQ.
#Distributed Systems
#Message Queue
#Storage
#Concurrency
Software Engineer
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System Design
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easy
Design a URL shortener service like Bitly.
#Hashing
#Database
#Caching
#Load Balancing
Software Engineer
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Technical
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medium
Explain the architectural differences between Docker and Kubernetes. Furthermore, how does Red Hat OpenShift add enterprise value on top of standard Kubernetes?
#Docker
#Kubernetes
#Red Hat OpenShift
#Containers
Software Engineer
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Technical
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hard
How does Garbage Collection work in Java? If an IBM microservice is experiencing high latency spikes due to 'Stop-the-World' pauses, how would you diagnose and tune it?
#Java
#JVM
#Garbage Collection
#Performance Tuning
Software Engineer
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Technical
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medium
Explain the CAP theorem. How does it apply when choosing between a relational database like IBM DB2 and a NoSQL database like Cassandra for a globally distributed application?
#Distributed Systems
#CAP Theorem
#SQL vs NoSQL
Software Engineer
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Technical
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easy
In Java 8 and later, what are the practical differences between an Abstract Class and an Interface? When would you choose one over the other?
#Java
#Object-Oriented Programming
Software Engineer
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Technical
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hard
How do you handle distributed transaction management across multiple microservices? Explain the Saga pattern.
#Microservices
#Distributed Transactions
#Saga Pattern
Software Engineer
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Technical
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medium
Walk me through setting up a CI/CD pipeline for a containerized application deploying to IBM Cloud. What tools and stages would you include?
#CI/CD
#Jenkins
#Tekton
#IBM Cloud
Software Engineer
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Technical
•
medium
What are the core differences between REST and GraphQL? In an enterprise environment, when would you advocate for using GraphQL?
#REST
#GraphQL
#Web Services
Software Engineer
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Technical
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medium
Explain the OAuth 2.0 authorization code flow. How would you secure a public-facing API gateway using OAuth?
#OAuth 2.0
#Authentication
#API Gateway
Difficulty Radar
Based on recent AI-sourced data.
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The "Standard" Interviewer
Senior EngineerFocuses on core competencies, system constraints, and clear communication.
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Think Out Loud
Always explain your thought process before writing code or drawing architecture.