The Ultimate Full-Stack Developer Interview Prep: 20 Must-Know Questions and Answers
March 25, 2023
logicrays
Full-stack development is a complex field with proficiency in front-end and back-end development. It is possible to succeed in this field with guidance and resources. Fresher candidates need help to prepare for the interview.
Check out our comprehensive guide and resources for full stack developer interview questionsto learn more about preparing for a job in full-stack development.
20 Must-Know Questions and Answers for Full-Stack Developer Interviews
The full-stack development interview questions are essential for job seekers preparing for interviews in this field. It covers many topics and helps candidates showcase their skills and knowledge.
1. What is Full Stack development?
Full-stack development refers to building and maintaining the entire web application stack, from the front-end user interface to the back-end server-side components and database.
A full-stack developer is proficient in both front-end and back-end development and can handle all aspects of the development process.
2. Describe the work profile of a Full Stack Web Developer?
The work of a full-stack web developer is to develop and maintain web applications that are functional, user-friendly, and visually appealing. It involves working on the front-end and back-end of the application, using a range of programming languages, frameworks, and tools.
A full-stack web developer is responsible for designing and implementing the user interface, developing server-side logic, managing databases, and ensuring the application is secure and scalable.
A full-stack web developer optimizes the application performance by integrating with third-party services. A full-stack developer has to collaborate with other team members, such as designers and project managers, to deliver high-quality software solutions.
3. What is CORS?
CORS stands for Cross-Origin Resource Sharing. It is a security feature implemented in web browsers that restricts web pages from making requests to a different domain or origin than the one that served the web page.
It prevents malicious websites from accessing sensitive user data or making unauthorized requests to other websites on behalf of the user.
4. Explain DevOps?
DevOps is a set of practices that combines software development (Dev) and information technology operations (Ops) to achieve faster and more reliable software delivery. It emphasizes collaboration and communication between development and IT operations teams and seeks to automate the software delivery process as much as possible.
DevOps involves several practices, including continuous integration (CI), continuous delivery (CD), and continuous deployment (CDep).
CI involves developers frequently integrating their code into a shared repository to catch and resolve bugs early in development.
CD ensures that software is always ready for deployment by continuously testing and validating code changes.
CDep involves automatically deploying code changes to production environments after they have been thoroughly tested and validated.
5. What is Inversion of Control?
Be prepared for this Full stack developer interview question and answer, as the interviewers will ask you sooner or later.
Inversion of Control (IoC) is a design pattern in software development that helps to achieve loose coupling between components and promotes better modularization and maintainability of code.
IoC frameworks provide a way to delegate the object’s creation and management to a container instead of manually creating objects and controlling their flow. At its core, IoC involves inverting the control flow in a software application to transfer the control from a high-level module to a low-level module.
It manages the dependencies between objects and provides them to the application when needed.
7. State the point of differences between Git Pull and Git Fetch?
It is a vital Full stack developer interview preparation asked during interviews. Here are a few key differences between the two:
Git fetch:
1. It retrieves the latest changes from a remote repository and stores them in your local repository remote-tracking branches.
2. The changes take time to merge with your local branch. It only updates the information about the remote branches without modifying any of your code.
3. The command git fetch only downloads the changes. It needs to integrate them into your local branch.
Git pull:
1. Git pull combines git fetch, and the git merge command.
2. It fetches the changes from the remote repository and merges them with your local branch in a single step.
3. When you run git pull, it automatically downloads the changes from the remote repository and merges them with your current branch. It updates both remote-tracking branches and your working branch.
8. State the Differences Between Function Constructors ES6 and ES5.
In ES5, function constructors create objects. It uses the function keyword and the object’s properties. Methods defined inside the function body use the keyword.
ES6 introduced a new syntax for creating classes in JavaScript, which makes it easier to create objects and is more similar to other programming languages. Class constructors are declared using the class keyword. Properties and methods get defined inside the class body.
Here is an example:
Differences:
1. Syntax: The syntax for creating objects using ES6 class constructors is more concise and easier to read compared to ES5 function constructors.
2. Inheritance: Inheritance in ES5 is achievable using prototype chains, whereas ES6 has a more intuitive syntax for inheritance using the keyword extends.
3. Super keyword: ES6 class constructors have access to the super keyword. It allows the constructor to call the parent constructor and inherit properties and methods from the parent class.
4. Strict mode: In ES6, class constructors are always in strict mode by default, whereas in ES5, you had to declare strict mode explicitly.
9. What is Multi-Threading? How is it used?
Multi-threading refers to the ability of a program to run multiple threads concurrently. A thread is a sequence of instructions that can be executed independently by a CPU. When a program is multi-threaded, it works on multiple- threads simultaneously. It allows one to perform several tasks at once.
Multi-threading improves the performance and responsiveness of an application.
It is an advantage for multi-core CPUs. A multi-core CPU has multiple processors, each of which can execute instructions independently. A program can take advantage of these multiple- processors to improve its performance by using multithreading.
Multi-threading implementation happens in a variety of programming languages and frameworks. In Java, for example, multi-threading can be implemented using the Thread class or the Executor framework. In Python, it can take place using the threading module.
10. Discuss AMD vs. CommonJS
Brace yourself for Full stack developer interview questions about the differences between AMD (Asynchronous Module Definition) and CommonJS (Common JavaScript) and which is better to use.
AMD and CommonJS are module systems. They organize code into reusable and maintainable modules in JavaScript. There are differences between the two:
1. Synchronous vs. Asynchronous: CommonJS is synchronous, meaning modules are loaded and executed synchronously when a program runs. AMD is asynchronous. It means modules can be loaded and executed asynchronously. It improves the program’s performance.
2. Browser vs. Server: CommonJS was designed for server-side JavaScript environments, such as Node.js, whereas AMD works on browser environments.
3. Syntax: CommonJS uses a require() function to load modules and a module. Exports object to export modules, whereas AMD uses a define a () function to define modules and a require() function to load modules.
4. Dependency Resolution: CommonJS resolves dependencies at runtime, whereas AMD resolves dependencies at compile time.
To sum up, AMD and CommonJS have advantages and disadvantages. The choice of which one to use depends on the project’s specific needs. In general, if you are working on a client-side application with much asynchronous loading, you might prefer AMD. If you are building a server-side application, CommonJS is the best choice.
11. What is Pair-Programming?
Pair programming is a software development technique in which two developers work together on the same codebase, computer, and keyboard, with one developer writing the code (the driver) and the other reviewing the code and providing feedback (the navigator).
The driver is responsible for writing the code and implementing the design, while the navigator is responsible for reviewing the code, identifying errors, and providing feedback.
12. How is GraphQL different from REST?
REST stands for Representational State Transfer. It is a popular architectural style for building web services. It uses HTTP requests to access and manipulate data. The data gets sent in JSON format. REST APIs have endpoints representing specific resources and are accessed using HTTP methods such as GET, POST, PUT, and DELETE.
Facebook developed the query language for APIs, GraphQL. It enables clients to request only the data needed and get a predictable response. Instead of multiple endpoints, GraphQL has a single endpoint responding to queries. Clients can specify their needs, and the server returns only that data.
The following are the specific points between GraphQL and REST:
1. Flexibility: In REST, the server defines the resources and their endpoints. Clients can only access the data exposed by the server. With GraphQL, clients can specify the data needed and get only that data. It gives clients more flexibility and control over the data they receive.
2. Over-fetching and under-fetching: REST APIs often suffer from over-fetching or under-fetching data. Over-fetching happens when a client requests more data than it needs, while under-fetching is when a client needs multiple requests to get all the data it needs. GraphQL provides clients with only the data they need. It reduces over-fetching and under-fetching.
3. Versioning: REST APIs often require versioning to maintain backward compatibility. The API evolves, and new versions get created to support new features. The clients must migrate to the new version to use those features. GraphQL eases clients’ queries as the API evolves without requiring a new version.
4. Performance: GraphQL can perform better than REST in some cases, as it reduces the amount of data transferred over the network. With REST, clients must make multiple requests to get all the data they need, while with GraphQL, they can get all the data they need in a single request.
13. What’s the difference between a Full Stack Engineer and a Full Stack Developer?
The terms Full Stack Engineer and Full Stack Developer are interchangeable, but there is a subtle difference between the two.
A Full Stack Developer is a software developer skilled in working with both front-end and back-end technologies. They are proficient in developing web applications using a combination of HTML, CSS, JavaScript, and one or more back-end languages such as Python, Ruby, or PHP. They have a good database understanding and server-side technologies and create a complete web application from scratch.
A Full Stack Engineer is a developer with the skills of a Full Stack Developer and a broader understanding of system architecture, scalability, and infrastructure. They are responsible for designing, implementing, and maintaining complex systems that require multiple technologies and platforms to work together seamlessly. They are also skilled in DevOps practices such as Continuous Integration and Continuous Deployment.
14. What is an event loop in Node.js?
An event loop is a fundamental concept in Node.js that enables it to handle multiple simultaneous connections and events without blocking the execution of code.
In Node.js, the event loop is a mechanism that allows Node.js to perform I/O operations asynchronously. When Node.js receives a request, it adds it to an event queue and starts working on other code.
Node.js then starts processing the events in the queue one by one, using a loop that continuously checks the queue for new events. When an event is processed, Node.js executes the corresponding callback function.
The event loop is essential in Node.js because it allows Node.js to handle large numbers of simultaneous connections without blocking the execution of code. For example, if Node.js is serving many clients over HTTP, it can handle multiple requests concurrently without creating a new thread for each request.
A single thread is used to handle all requests In Node. js. The event loop ensures that the execution of code is not blocked while waiting for I/O operations to complete.
15. What is RESTful API?
RESTful API (Representational State Transfer Application Programming Interface) is an architectural style for building web services that follow a set of constraints and principles. A RESTful API is stateless, cacheable, and scalable, and it uses HTTP methods to access and manipulate resources.
16. What are the differences between Server-side Scripting and Client-side Scripting?
Server-side scripting refers to scripts executed on the server before the web page gets sent to the client. In this approach, the server generates HTML, CSS, and JavaScript code based on the request from the client.
The server-side code can interact with databases, file systems, and other server-side resources. PHP, Python, Ruby, and Java are examples of Server-side scripting languages
Client-side scripting, on the other hand, refers to scripts executed on the client’s web browser after the web page is loaded. The client-side code can modify the page’s HTML, CSS, and JavaScript codes based on user interaction or other events. Client-side scripting languages include JavaScript, CSS, and HTML.
The differences between server-side scripting and client-side scripting are:
1. Execution: Server-side scripts are executed on the server, while client-side scripts are executed on the client’s web browser.
2. Resources: Server-side scripts can access server-side resources such as databases, file systems, and other server-side services, while client-side scripts can only access client-side resources such as the DOM (Document Object Model) and browser APIs.
3. Security: Server-side scripts are more secure than client-side scripts because they are non-exposable to the client’s browser. Client-side scripts can be viewed and modified by the client, which makes them vulnerable to security risks such as cross-site scripting (XSS) attacks.
4. Performance: Server-side scripts can be slower than client-side scripts because they require communication between the client and server. Client-side scripts can execute more quickly because they are executed locally on the client’s browser.
17. What is the prototype in JavaScript? How do you use it?
In JavaScript, every object has a prototype. It is an object that serves as a blueprint for the object. The prototype defines the object’s properties and methods. It is used as a fallback when the object does not have a property or its method.
A series of links between objects make a prototype chain. This chain allows objects to inherit properties and methods from their prototypes.
You will have to define methods and properties on the prototype object to use the prototype in JavaScript. You can access the object’s prototype using the Object.getPrototypeOf() method or the __proto__ property. It then gets shared by all instances of the object.
Here is an example of how to use the prototype in JavaScript:
JavaScript
// Define a Person object constructor
function Person(name, age)
{ this.name = name;
this.age = age; } //
Insert Person prototype to the methodPerson.prototype.sayHi = function() {
console.log(`Hi, I am is ${this.name}`); } //
Create a new instance of the Person object const Richard = new Person('Richard', 30); //
The label on the Richard objects says Hi method
Richard.sayHi(); // Output: "Hi, I am Richard"
In the example above, we defined a Person object constructor and added a sayHi method to the prototype object. When we create a new Person object instance, the sayHi method is available to that object through the prototype chain. We then called the sayHi method on the Richardobject. The result is “Hi, I am Richard.”
18. What is Dependency Injection?
Dependency Injection is a software design pattern that allows objects to depend on other objects without creating them directly. Dependencies pass to the object via its constructor or properties. It helps to decouple objects and promote modular, reusable code.
Dependency Injection encounters in frameworks such as Spring, Angular, or React. These frameworks use Dependency Injection to manage object dependencies and improve the modularity and flexibility of the application.
19. What is a connection leak in Java? How can we fix it?
A connection leak in Java occurs when a database connection is not properly closed after use, resulting in the connection remaining open and unavailable for other database operations. It can cause-
1. To run out of connections available.
2. Performance issues
3. Application crashes.
As a full-stack developer, there are several ways to fix a connection leak in Java:
1. Close connections: Close database connections when they are no longer needed.
2. Use connection pools: Implement a connection pool to manage database connections. The connection pools allow you to reuse connections rather than create new ones each time, reducing the risk of leaks.
3. Use try-with-resources: Use try-with-resources. It ensures database connections are automatically closed when the try block exits, even with an exception.
4. Use a connection leak detection tool: Utilize a connection leak detection tool to identify and fix any leaks in your application.
20. Give an example of a project you have worked on and the technologies involved. How did you make these choices?
One project I worked on was a web application for a healthcare organization. We wanted to create a platform for patients to schedule appointments, view their medical records, and communicate with their healthcare providers.
For the front end of the application, we chose React because of its modular architecture, ease of use, and popularity in the industry. We also used Redux for state management and React Router for navigation.
We used Node.js with Express as the server framework for the back end. We used MongoDB as the database because it offered scalability and flexibility in data storage.
We also utilized libraries and tools such as Bootstrap for styling, Passport for authentication, and Socket.io for real-time communication.
We chose technology based on the project requirements, our team’s expertise, and industry trends. We needed a front-end framework that was easy to work with, scalable, and offered good performance. React met all of these requirements and was a natural choice.
For the back end, we wanted a technology that allowed for fast development, offered good performance, and had a large community. Node.js fit the bill perfectly. We chose Express as it is a popular framework that is easy to use and has good documentation.
We created a successful web application that met the healthcare organization and its patients.
Final Thoughts
Preparing for a full stack developer interview is crucial for landing a high paying job in this highly competitive field. It requires extensive knowledge of front-end and back-end development technologies, problem-solving skills, and a strong portfolio.
It’s essential to get trained by experts who can provide you with the necessary guidance and resources to succeed.
LogicRays Academy is one such platform that offers comprehensive full stack developer interview preparation to help candidates prepare for their dream job.
Contact us today and start your journey to becoming a successful full-stack developer today with LogicRays Academy.
FAQs While Preparing For A Full-Stack Developer Interview
How to introduce yourself in an interview as a full stack developer?
As a Full Stack Developer, I am skilled in front-end and back-end development, utilizing languages such as JavaScript, HTML, and CSS, and frameworks such as React, Angular, and Node.js. I have experience with database management, software development methodologies, and project management.
What are the basic skills required for a full-stack developer?
A Full Stack Developer should possess robust front-end and back-end development skills, including languages like JavaScript, HTML, and CSS, and frameworks like React, Angular, and Node.js. You should also learn about database management, software development methodologies, and project management and possess problem-solving and communication skills.
What to do to prepare for an interview for a position as a Full Stack Developer?
To prepare for a Full Stack Developer interview, one should thoroughly review and practice with relevant technologies and tools, such as HTML, CSS, JavaScript, React, Angular, Node.js, and databases like MySQL or MongoDB. Familiarizing oneself with design patterns, software development methodologies, and version control tools like Git, and practicing problem-solving and communication skills are also important. Go through full stack developer interview questions, and you will be able to crack the interview.
How do I get my first full-stack developer job?
To get your first Full Stack Developer job, focus on building a skill set by practicing and contributing to open source projects, participating in online communities, and attending conferences or meetups. Build a strong portfolio that showcases your work and skills and apply to relevant job openings, internships, or apprenticeships to gain experience and exposure.
