Top Software Engineering Interview Questions
Software development is a vast field with a lot of potential, and the demand for software engineers is growing. If you’re a software engineer, developer, or someone involved in the tech industry, securing a position at a top tech company like FAANG would be a dream. And in order to make this dream a reality, you must appreciate the importance of the software engineering interview.
Preparing for technical interviews can be a daunting and time-consuming task. Honestly, nobody has the time to solve hundreds of leetcode-styled questions to prepare for software engineering interviews. Preparing for technical interviews can be a daunting and time-consuming task. Honestly, nobody has the time to solve hundreds of leetcode-styled questions to prepare for software engineering interviews. Developers need a shorter yet effective way to prepare. Software engineering interview prep requires quality content and a straightforward plan. And that is where you need expert help.
Keeping in mind software engineers’ busy schedules and the importance of technical interviews, we’ve also created Educative-99 and Educative-77 in the top five coding languages (Python, Java, JavaScript, Go, and C++). Moreover, to help you understand the interview prep process, we’ve added some commonly asked questions for both beginner and expert software engineers in this blog! Look at the queries and analyze how well you’re prepared for your technical interview.
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Software Engineering Interview Questions for Beginners#
What is the difference between a class and an object in OOP?
A class is a blueprint or template for creating objects. It is a user-defined data type that has its own members and functionalities. It defines the structure and behavior of objects created from the class. Classes encapsulate data and behavior that are common to a group of objects.
Explain the concept of data structures. Give an example of when you would use an array versus a linked list.
Data structures are a way of organizing and storing data to perform operations on that data efficiently. Data structures can be categorized into two main types: linear and nonlinear.
The following are instances when you should use an array:
You have a fixed number of tasks and need quick access to any task using its index.
The size of the task list doesn’t change often.
The following are instances when you should use a linked list:
The number of tasks can change dynamically (tasks added or removed frequently).
You need to insert or delete tasks efficiently, especially in the middle of the list.
What is the difference between a function and a method?
A function is a block of code that can perform a specific task or calculation. It is not related to any specific object or class and can be called independently. In many programming languages, functions are defined using the “function” keyword or a similar construct.
A method is a function that is associated with a particular object or class. Methods are typically defined within a class definition and can be called on instances (objects) of that class. They often have access to the object’s attributes and can interact with them.
What is software re-engineering?
Software re-engineering is reverse engineering. It is a process of analyzing, modifying, and making changes in the existing software. The purpose of software re-engineering is to remove bugs or improve the quality of existing software.
What activities fall under the category of umbrella activities?
The following software activities are umbrella activities:
Software Project Tracking and Control
This activity involves monitoring, managing, and tracking tasks, schedules, resources, and software project progress.
Risk Management
Risk management is the process of identifying, assessing, and mitigating risks that can impact the success of the project. It involves creating a risk-management plan, conducting risk assessments, and implementing strategies to minimize the likelihood and impact of potential issues.
Software Quality Assurance
Quality assurance activities ensure that the software product meets the specified quality standards and requirements.
Formal Technical Reviews
Formal technical reviews are structured evaluation processes where experts examine software artifacts such as code, design documents, and requirements.
Software Configuration Management
Configuration management involves managing and controlling software changes and associated documentation changes. It ensures that changes are properly tracked, evaluated, and documented, preventing unintended consequences and maintaining the integrity of the software.
Reusability Management
Reusability management involves identifying opportunities for code and component reuse across different projects or within the same project.
Measurement
Measurement involves defining and collecting relevant metrics and data to assess the progress and quality of the project.
What is version control, and why is it important in software development?
Version control, also known as source code control, is a system used in software development to track and manage changes to source code and other project-related files over time. Version control systems help developers change the source code as needed. This system provides a structured way to record modifications, additions, and deletions made to files and allows multiple developers to collaborate on a project efficiently.
Can you explain the basic steps of the software development lifecycle (SDLC)?
The Software Development Lifecycle (SDLC) consists of seven basic steps:
Planning
Gathering requirements & analysis
Design
Coding & implementation
Testing
Deployment
Maintenance
What is black-box testing?
Black-box testing is a software testing technique that focuses on examining a software system’s functionality without having detailed knowledge of its internal code or implementation. In other words, black-box testing treats the software as a “black box” where the tester is primarily concerned with the input and output of the system, and the internal logic or structure is not considered during the testing process.
Software Engineering Interview Questions for Experts#
What are the differences between quality assurance and quality control?
Quality Assurance | Quality Control |
QA focuses on the defects, bugs, and problems that occur prior to development. | QC is a reactive process focused on identifying and correcting defects or issues after the development phase. |
The primary purpose of QA is to improve and optimize processes to prevent defects, reduce variability, and ensure that the final product or service consistently meets quality standards. | The primary purpose of QC is to identify defects or deviations from quality standards in the final product or service and take corrective actions to address them. |
QA is the responsibility of the entire organization, including management, process owners, and employees. | QC is typically the responsibility of specialized teams or individuals who perform inspections, testing, and quality checks on the final product or service. |
QA activities occur throughout the entire development or production process, from initial planning to final delivery. | QC activities typically occur after the product or service has been produced or developed and are focused on evaluating the end result. |
Given the root node of a binary tree, swap the ‘left’ and ‘right’ children for each node.
To swap the ‘left’ and ‘right’ children for each node in a binary tree , you can use Depth first traversal and Bottom up mirroring approach.
What is polymorphism?
Polymorphism is one of the four fundamental principles of OOP, known as the “Four Pillars of OOP,” along with encapsulation, inheritance, and abstraction. In object-oriented programming (OOP), polymorphism allows objects of different classes to be treated as objects of a common superclass. It enables you to write more flexible and reusable code by providing a way to work with objects in a general, abstract manner rather than having to deal with the specific implementation details of each class.
What is the difference between tags and branches?
Tags and branches in version control systems like Git serve distinct purposes. Tags are used to mark specific points in the history of a repository, typically indicating milestones or releases. In contrast, branches are used for active development and collaboration, focusing solely on the changes and working on them independently before potentially merging them into the main codebase.
Define concurrency.
Concurrency is a computing concept where multiple tasks or processes appear to be executing simultaneously, allowing for a more efficient and responsive utilization of system resources. In a concurrent system, tasks can overlap in time, executing in parallel, even on a single-core processor, through time-sharing or interleaved execution.
Concurrency is important for improving system performance, response time, and resource utilization.
7 Bonus Software Engineering Questions to Prepare#
1. What is Big-O notation, and how do you use it to compare solutions?#
Answer: Big-O describes the upper bound on how time or space grows with input size n. It lets you compare algorithms independent of hardware by focusing on growth rates (e.g., O(1), O(log n), O(n), O(n log n), O(n²)).
Lists/arrays: index O(1), search O(n), insert/delete middle O(n)
Hash map: average insert/get O(1), worst O(n) if many collisions
Balanced BST (e.g., Red-Black): insert/get O(log n)
Sorts: Quick/Merge average O(n log n), Insertion O(n²) but great for tiny or nearly sorted inputs
Interviewers want you to pick the right data structure and justify trade-offs (e.g., hash map vs. tree map when you need ordering). Also mention constant factors and cache behavior when choices are close.
2. Process vs. thread vs. coroutine—and sync vs. async?#
Answer:
Process: isolated memory space; robust but heavier to create/context-switch.
Thread: shares process memory; cheaper than processes but needs synchronization (locks, atomics) to avoid races.
Coroutine/async task: user-space scheduling that yields at await points; extremely cheap to create/switch; great for I/O bound workloads.
Synchronous: call blocks until completion.
Asynchronous: call returns immediately; completion signaled via callback/promise/await.
Use cases:
CPU-bound parallelism: multiple processes or threads with work chunking.
I/O-bound concurrency at scale: async coroutines (e.g., Node.js, asyncio, Kotlin coroutines) to avoid thread explosion.
Hybrid: CPU pools for heavy compute + async I/O for everything else.
3. How do database indexes work, and when can they hurt performance?#
Answer: Indexes are auxiliary data structures (commonly B-trees or hash indexes) that speed up lookups at the cost of extra writes and storage.
B-tree: ordered, supports range queries (BETWEEN, <, >) efficiently.
Hash: fast equality lookups, no order/range support.
Design tips:
High-selectivity columns benefit most (e.g., email).
Composite index (A, B): only helps queries with a left prefix (A or A, B), so order matters.
Covering index: includes all referenced columns—query can be satisfied from the index alone.
Pitfalls:
Too many indexes slow INSERT/UPDATE/DELETE (each change updates multiple indexes).
Low-cardinality columns (e.g., boolean) rarely help.
Functions on columns can defeat indexes unless you use functional indexes.
4. Explain common caching strategies and consistency concerns.#
Answer:
Cache-aside (lazy-load): app reads cache first; on miss, reads DB, then populates cache. Simple, popular; stale data risk until TTL/invalidations.
Write-through: writes go to cache and DB synchronously; read hits are warm, but write latency increases.
Write-back (write-behind): write to cache, flush to DB later; fastest writes but risk of data loss if cache fails before flush.
Key practices:
TTL and explicit invalidation on update.
Prevent cache stampede with request coalescing or single-flight locks.
Use idempotent writes and versioning (ETags) to avoid overwriting newer data.
For user sessions in distributed systems, prefer stateless services + centralized cache (e.g., Redis) instead of sticky sessions.
5. REST vs. gRPC vs. GraphQL — when to use which?#
Answer:
REST (JSON over HTTP): human-readable, cacheable, great for public APIs and browser clients. Use when you need simplicity and wide tooling support.
gRPC (HTTP/2 + Protobuf): compact, strongly typed contracts, bi-directional streaming; ideal for service-to-service communication and low-latency mobile/backend links.
GraphQL: clients request exactly the fields they need; reduces over/under-fetching for complex UIs. Requires a schema and careful N+1 query avoidance.
Also discuss idempotency (e.g., PUT/DELETE should be idempotent), versioning (URL or header), and backward compatibility strategies (tolerant readers, additive changes).
6. How do you design for scalability and high availability?#
Answer:
Scale up vs. scale out: add bigger machines vs. add more machines.
Stateless services behind a load balancer (round-robin/least-conn) simplify horizontal scaling.
State management: move state to managed stores (DBs, caches, object storage); avoid sticky sessions.
Partitioning/sharding: split data by key to remove single-node bottlenecks; plan for rebalancing and hot shards.
Replication: primary/replica(s) for read scaling and HA; understand read-after-write and eventual consistency trade-offs.
Failure domains: deploy across zones/regions, use health checks and auto-healing.
Backpressure & queueing: smooth spikes with message queues; consumers scale independently.
7. What is observability (logs, metrics, traces), and how do SLI/SLO/SLA fit in?#
Answer:
Observability is your ability to understand internal system state from external outputs:
Logs: detailed event records for debugging; structure them (JSON) and include correlation IDs.
Metrics: numeric time series (latency, error rate, QPS, saturation). Power dashboards and alerts.
Distributed traces: end-to-end request timelines across services; identify where latency/Errors occur.
Reliability terminology:
SLI (Service Level Indicator): what you measure (e.g., p99 latency, success rate).
SLO (Objective): the target (e.g., 99.9% success over 30 days).
SLA (Agreement): contractual commitment + penalties.
Use error budgets to balance reliability vs. feature velocity, and patterns like retries with jittered exponential backoff, timeouts, and circuit breakers to make clients resilient.
Questions to ask as an Interviewee during Software Engineering Interview#
You’ve made it through the technical and behavioral components of your software engineering interview, and it’s time to wrap things up with some interview questions of your own.
As a job applicant, you’ve likely spent countless hours honing your technical skills, reviewing data structures and algorithms, and rehearsing explanations of different solutions and tradeoffs. Not to mention the time spent on perfecting your answers to behavioral interview questions. The time and effort you spent to get here were valuable, which is why it’s important to avoid blindly accepting job offers without thoroughly vetting the company itself. Acing your job interview means not only demonstrating technical skills and problem-solving abilities but also evaluating whether the company aligns with your personal and professional goals.
Contrary to what some may think, being selective is actually doubly important if you’re looking for your first software engineering role. As an entry-level software engineer candidate, you must ensure that your first job will provide valuable learning opportunities that will set you up for success in later roles. Ignoring potential red flags and settling for a toxic workplace to get your foot in the door can put you at risk for burnout.
As a rule of thumb, you should always come prepared with your own questions for hiring managers and, sometimes, recruiters. Many candidates overlook this critical aspect of the interview process: asking the right questions in return.
Today we’ll look at 6 categories of questions you can use to find out if a company is a good fit or a road to nowhere.
Let’s get started!
We’ll cover:
The dos and don’ts of interviewing your interviewer#
In a job interview, remember that you’re also interviewing the company to see if it’s a good fit for you. Make sure you understand the company’s mission and values. If you find a company whose values overlap with yours, you’ll build a career that’s both meaningful and rewarding.
Before we get straight into the interview questions, here are a few tips to remember as you prepare for the job interview. Most of these are just common sense, but a quick refresher on interview etiquette never hurts!
Do | Don’t |
Listen actively, take notes if necessary, and follow up with clarifying questions | Speak negatively about a previous employer or coworkers |
Research the company before your interview and be prepared to discuss any relevant topics that come up | Ask the interviewer what product or service their company sells — this is the kind of information you should come in knowing |
Wrap up your line of questioning by asking about the next steps in the interview process | Appear disinterested or distracted |
Express enthusiasm and interest in the role | Ask invasive personal questions that are unrelated to the company or interview |
Use coarse or unprofessional language |
3 tips for using this guide#
Rank these 6 categories by order of importance. You have limited time to ask your interviewer these questions, so it’s good to narrow them down in a way that helps you quickly identify whether or not a company aligns with your top priorities.
Try answering your own questions. Jotting down a few notes about what you want to hear and what you don’t in response to a question can help you consider offers more carefully. Having a set of defined standards in place will help you quickly flag any potential red flags that may arise in conversation.
Tailor your questions where appropriate. If you have personal or professional goals that motivate a specific line of questioning, fine-tuning your questions can help the interviewer provide more relevant answers that directly address your interests.
E.g., “What opportunities are available for professional development and continuous learning?” can turn into, “I’m interested in developing expertise in System Design. Are there professional development opportunities available to help me reach my goal?”
Software Engineer Interview Questions#
1. Company culture and work environment#
These questions help candidates understand the company’s values, work-life balance, and overall atmosphere.
Can you describe the company culture and what makes it unique?
How do you promote a healthy work-life balance within the team?
How would you describe the company’s management style?
What do day-to-day tasks look like for a software engineer on the team?
2. Team dynamics and collaboration#
These questions provide insight into how teams work together, communicate, and make decisions.
How are new team members onboarded and integrated into the team?
Can you tell me about the team I would be working with? What are their backgrounds and roles?
How do team members collaborate on software projects? Do you use any specific tools or methodologies for project management?
How are decisions made within the team? Is it a top-down approach or more collaborative?
3. Technical stack and infrastructure#
These questions help candidates understand the company’s technology stack and infrastructure, allowing them to gauge if it aligns with their skills and interests.
There’s a lot of variety when it comes to software development tech stacks, so you’ll want to tailor your interview questions to suit your role in the development process — for example, if you’re looking for back-end developer roles, you’ll want to know more about what technology is used in the company’s back-end.
If you’re a front-end web developer, you can generally assume that HTML, CSS, and JavaScript will be part of your job.
Can you provide an overview of the technology stack used by the team?
Are there any plans to adopt new technologies, programming languages, or frameworks in the near future?
Can you describe the deployment process and release cycles?
How does the company handle infrastructure and deployment? Do you use cloud-based services, on-premises, or a hybrid approach?
How does the company manage technical debt?
4. Professional development and growth#
Ensuring the company supports your growth is key to building a successful career. Consider these questions:
What opportunities are available for professional development and continuous learning?
What is the company’s approach to continuous learning and skill development?
Are there any internal resources, such as workshops or training courses, available to employees?
How does the company support employees in attending conferences or industry events?
5. Performance evaluation and feedback#
These questions give candidates an idea of how their work will be assessed and what kind of feedback they can expect.
How is performance evaluated for software engineers within the company?
What is the feedback process like? How often do employees receive formal and informal feedback?
Can you describe any mentoring or coaching programs available to current employees?
What metrics or key performance indicators (KPIs) will be used to evaluate my performance in this role?
6. Company vision and future projects#
These interview questions allow candidates to understand the company’s long-term goals, upcoming projects, and overall direction. It’s not necessarily essential, but it can be helpful to understand how the company handles project management and product management to get a better sense of the workflow.
What are the company’s most exciting upcoming projects or initiatives? Can you share some insights into the company’s long-term vision and goals?
How does the team I’d be joining contribute to the company’s overall success?
How does the company plan to stay ahead of industry trends and competition?
Can you share any recent successes or milestones the company has achieved?
Wrapping Up!#
Thoroughly preparing for your technical interview is crucial to securing your dream job. You can find tons of interview prep content online, which might seem great at first, but the overwhelming amount of information can distract you easily. In this blog, we’ve mentioned a few frequently asked questions for beginners and experienced developers alike. But you need more than these questions to prepare you for the top tech companies. For that, Educative offers a variety of
Happy Learning!
