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It’s never simple to prepare for a software developer interview, particularly if you’re unfamiliar with the company’s primary tech stack. This is why one of the keys to success for various backend developer jobs is knowing what kinds of questions you could be asked during a technical interview.

You must demonstrate more than just technical proficiency when preparing for a backend developer interview; you must also explain how your choices meet stakeholder demands and produce quantifiable business results.

Keep reading and exploring to get the most important backend developer interview questions. Moreover, we will also explain how to get a job as a backend developer in 2026.

Key Takeaways

• Strong coding, system design, and problem-solving abilities are necessary for backend developer jobs.
• Understanding databases, cloud, security, and APIs is essential for interview success.
• Practice and real-world projects enhance work preparedness.
• Both technical and business knowledge are necessary for backend positions.
• In 2026, recruiting success is increased by organized preparation.

What is The Job Of Backend Developer?

Technical proficiency, critical thinking, and strong teamwork are necessary for backend developer jobs. You should be able to construct the web infrastructure on your own as a backend web developer.

What many backend developers perform daily is as follows:

• Create and manage websites: The primary duty of a backend developer is to discover the most effective way to create user-friendly, intuitive prototypes and transform them into websites using a variety of tools, frameworks, and programming languages. This necessitates knowledge of cross-platform compatibility and functioning.
• Write excellent code: Clean, readily maintainable code is essential for developers to create long-lasting web apps.
• Conduct quality assurance (QA) testing: Establish and manage testing plans to enhance the user interface and experience, guaranteeing the best possible presentation across a range of browsers and devices.
• Evaluate speed and efficiency: After a website is operational, developers must evaluate its scalability and performance during updates and modifications, making any required code adjustments.
• Debugging and troubleshooting: Be able to identify and fix problems while sharing them with QA teams, project managers, and stakeholders.

Top 30+ Backend Developer Interview Questions For Different Backend Developer Jobs In 2026

Here are the different backend interview questions and answers you must prepare as a beginner:

1. Describe An API Endpoint

A particular URL that serves as a gateway to a certain service or a feature inside a service is known as an API endpoint. Client apps can communicate with the server via an API endpoint by sending requests (and occasionally even payload data) and getting a response from it. Typically, a single server feature can be mapped to each endpoint. However, this is one of the best backend interview questions for different backend developer jobs.

2. Could You Describe The Distinction Between NoSQL And SQL Databases?

Relational databases, sometimes referred to as SQL databases, rely on a predetermined schema (or structure) for their data. Every time you describe a record or table in the database, you do it using its format (fields and name).

There is no schema in NoSQL databases, hence the data has no predetermined organization. Even though they theoretically represent the same item, collections of records are typically not required to have the same structure.

Also Read: Ultimate Guide To Backend Web Development: Details and Required Skill Set

3. How Would a New Feature Be Implemented On The Backend?

Describe how requirements are gathered, technical design documents are created, database modifications are planned, unit and integration tests are written, peer reviews are conducted, the CI pipeline is set up, blue-green or canary releases are made, and post-deployment monitoring is done.

4. Which Seven Layers Make Up The OSI System Model?

According to the Open Systems Interconnection model or OSI Model, information must pass through seven abstract layers with distinct functionalities in order to be traced from one application to a physical device to software in another computer. Physical, data connection, network, transport, session, presentation, and application are these levels.

5. What Is Containerization, And What Are The Advantages For Backend Development?

Applications and their dependencies may be packaged using this lightweight virtualization technique, guaranteeing consistent environments across many computers. Furthermore, by streamlining deployment procedures and minimizing conflicts between software versions and settings, it offers isolation and portability, which is really advantageous for different backend developer jobs.

6. When Troubleshooting A Backend Application, What Tools And Methods Do You Employ?

Using the IDE itself would be a straightforward approach if the backend application being debugged is located on the local development computer. Debugging features are included in the majority of contemporary IDEs, including IntelliJ, Eclipse, and others.

7. How Would You Handle Batch Processing In A Backend Application That Uses A Lot Of Data?

Using a batch-processing framework like Hadoop or Spark would be the best choice in this situation. They are already equipped to handle enormous volumes of data concurrently.

8. Which Backend Programming Languages Are The Most Crucial?

Backend developers frequently use Java, Python, PHP, Node.js, and Go. However, the needs of the project determine the language to use. Each language also has robust libraries and different frameworks. Thus, it is more important to study one thoroughly than to learn several superficially. Furthermore, mastering fundamental ideas applies to all backend development jobs.

9. What Is REST API?

Systems can interact via HTTP techniques thanks to a REST API. Additionally, it makes use of structured replies and stateless queries. As a result, it increases simplicity and scalability. Furthermore, JSON data is frequently sent via REST APIs. As a result, they predominate in contemporary backend interview questions and backend developer jobs.

10. Describe ORM

Database tables are mapped to objects via ORM. Additionally, it uses less raw SQL. As a result, engineers produce code that is cleaner. ORMs also increase productivity. But abuse might lead to problems with performance. ORM comprehension is frequently tested in interview questions for developer roles.

11. Describe Caching

Data that is regularly retrieved is momentarily stored using caching. Additionally, it lessens the database burden. Applications react more quickly as a result. Programs like Redis also enhance scalability. Caching expertise is therefore essential for backend developer positions.

12. Describe The Characteristics Of ACID

ACID guarantees database dependability. Complete transactions are guaranteed by atomicity. Data integrity is preserved via consistency. Conflicts are avoided via isolation. Data is preserved after failures thanks to durability. Consequently, ACID principles are essential. These are standard questions during backend interviews.

Also Read: Ruby on Rails vs Django: Best Framework For Backend Development

13. What is Microservices Architecture?

Applications break down into separate services using microservices. Additionally, every service scales independently. Deployments become more adaptable as a result. Failures also remain isolated. But complexity rises. In today’s backend developer positions, knowing this is helpful.

14. Explain Monolith Vs Microservices

A monolith is a single database. Distributed systems are microservices. Monoliths are also initially simpler. Microservices, however, scale more effectively over time. Thus, the choice of architecture is important. Interview questions for backend developers frequently make this connection.

15. Describe Load Balancing

Traffic passes across servers using load balancing. Additionally, it avoids overloads. As a result, system availability increases. It also improves fault tolerance. For projects with a lot of traffic, backend engineers need to know this for different backend developer jobs.

16. What Is API Rate Limiting?

The frequency of requests is limited by rate limiting. It also stops abuse. As a result, system stability increases. It also safeguards backend resources. As a result, rate limitation is a common topic in developer interviews.

17. What is Docker?

Applications are packaged into containers using Docker. Additionally, containers provide uniformity between environments. Deployments become dependable as a result. Docker commands also make scalability easier. Jobs for backend developers are increasingly requiring this ability.

18. What Is CI/CD?

CI/CD can automate testing and deployment of a process. It also lessens human mistakes. As a result, development accelerates. It also guarantees regular releases. Backend interview questions need an understanding of CI/CD pipelines.

19. Describe Normalization In Databases

Normalization effectively arranges the data in databases. Additionally, it lessens repetition. Consequently, data integrity gets better. On the other hand, performance has an impact on over-normalization. As a result, backend engineers carefully balance normalization.

20. How Do You Measure And Track Backend Application Performance?

Using an Application Performance Management system (APM) like New Relic, AppDynamics, or even Dynatrace is an excellent method to keep an eye on the performance of backend apps. With the least amount of work on your behalf, they will monitor the performance of your application and reveal any bottlenecks.

21. Describe Session Management

You can monitor user activity using session management. Additionally, it securely saves the state. As a result, user experiences stay the same. You can also use cookies and tokens for sessions. For professions involving backend developer jobs, this subject is essential.

22. Describe The Following Nine Server Response Error Codes: 200, 204, 201, 301, 400, 401, 404, 409, And 500

200 is “OK,” and everything went well. A 201 “Created” message indicates that the system created a resource at the client’s request. A 204 “No Content” code indicates that no status was returned by the server. A 301 “Moved Permanently” notice indicates that a client-triggered action altered the resource URI. A 400 “Bad Request” error indicates a client-side problem.

A 402 “Unauthorized” code appears if the client fails to supply the proper authentication. A 404 “Not Found” response indicates that a mapped resource could not be located. Code 409, “Conflict,” is returned in an inconsistent or impossible condition. Code 500, which is defined as “Internal Server Error,” is produced by server-side faults.

23. Describe Pagination

Large datasets come in different pages via pagination. It also decreases the magnitude of the reaction. As a result, performance increases. Pagination also improves the user experience. Interview questions for developer jobs frequently include this.

24. What Does Logging Entail?

Logging is the process that records the system events. Additionally, it facilitates debugging. Errors are therefore simpler to identify. Structured logs also enhance monitoring. Backend developer jobs require an understanding of logging.

25. What Distinguishes a POST Request From a GET Request?

Consider POST as an author submitting a new manuscript and GET as a librarian collecting a book. CDNs may cache GET requests since they are secure, idempotent, and pass arguments in the URL. To create or edit records, POST requests provide a body—JSON, form-data, you name it. In order to avoid cache problems and adhere to REST best practices, we changed a few unintentional state-changing GET calls to POST during a recent audit.

26. How Have You Handled Backend System API Dependencies?

Using API versioning is a wonderful method to manage API dependencies in backend systems. Even if there are several versions of the API, you can make sure that your systems are utilizing the correct one by following this easy procedure.

Additionally, you may use different versions of the same API across several backend systems without worrying about updates damaging your systems or causing inconsistencies.

27. Describe Cloud Computing

Cloud computing offers on-demand resources. It also lowers the cost of infrastructure. Scalability thus becomes simpler. Furthermore, backend systems are dominated by services like AWS. Interview questions for backend developers require a thorough understanding of the cloud.

28. What Is Error Handling?

Error management controls unforeseen malfunctions. It also keeps crashes from happening. Applications remain constant as a result. You can enhance debugging using explicit error messages. For backend developer jobs, this is crucial.

29. How Can Idempotency Be Handled In REST API Design?

You may use HTTP verbs for REST APIs, such as GET, PUT, and DELETE, to specify your idempotent actions. If the client consistently provides the same key, you can also manually construct a key-based logic to prevent performing the same operation repeatedly.

30. What Are Correlation Ids, And How Many Requests Can Be Tracked Between Services Using Them?

Correlation IDs are distinct identifiers that are appended to requests sent to distributed architectures in order to make request tracking easier across the architecture. Recall that the data from a request often travels via several web services before producing a response when it reaches a distributed backend system. This makes it simple to comprehend the path that every request takes in order to troubleshoot any possible difficulties or performance concerns.

31. Dependency Injection: What Is It?

Dependency injection actually manages object dependencies. Additionally, it enhances testability. As a result, programming becomes adaptable. It also promotes clean architecture. Interview questions for backend developer jobs frequently touch on this subject.

32. Talk About Methods For Stopping And Identifying Abnormalities In Data In Large-Scale Systems

Typical methods include the following:

• To stop incorrect data from entering, you should add validation procedures and put them into practice. Data anomalies can define defining schemas and using schema constraints to enforce minimal standards.
• Use data versioning so that you can quickly go back if any abnormalities are found.
• Establish a robust data quality procedure to guarantee that any data that enters your system is appropriately verified and, if necessary, highlighted.

How To Get A Job As A Backend Developer?

Here are the steps you can follow to become a backend developer and apply for different backend developer jobs:

• Learn one fundamental backend language first, such as Python, Java, or Node.js, thoroughly.
• Next, comprehend algorithms, data structures, and fundamental computer science ideas.
• Next, learn how to write useful queries for master databases, such as SQL and NoSQL.
• After that, one must have a comprehensive understanding of REST APIs and API design concepts.
• Practice backend security principles, authorization, and authentication as well.
• Additionally, comprehend request lifecycles, HTTP protocols, and server principles.
• Next, work with frameworks like Django, Spring Boot, or Express.js firsthand.
• Additionally, learn how to collaborate using Git and GitHub for version control.
• Additionally, investigate ideas related to scalability, performance optimization, and caching.
• Next, familiarize yourself with AWS and Azure as well as Docker.
• Crucially, create realistic applications to demonstrate backend abilities.
• Lastly, prepare interview questions for backend developers and confidently apply for backend developer positions.

FAQs (Frequently Asked Questions)

What Does A Backend Developer Do?

A backend developer creates and manages the databases, infrastructure, and secret server-side logic that drive websites and apps.

Is Backend Still In Demand?

Because companies depend on reliable server-side systems, backend development is still in great demand. Moreover, it is a steady and profitable sector.

Do I Need SQL For Backend?

Indeed, a basic and necessary ability for backend engineers is SQL understanding.

How Much Do Backend Devs Make?

In the United States, backend developer wages typically range from entry-level positions of about $70k–$80k to senior jobs reaching $120k–$150k+; they can vary greatly depending on region, expertise, and tech stack.

Conclusion

High-performing applicants stand out in backend developer interviews through regular practice and focused feedback. With an emphasis on quantifiable effect and stakeholder alignment for various backend developer jobs, use this guide to organize your preparation. Your capacity to convey both technical proficiency and production awareness improves with each practice session. Recall that your ability to reply confidently and clearly is just as crucial as your technical proficiency for interview questions for developer.