Full Stack Developer Interview Questions

Most Common Full Stack Interview Questions and Answers

What Is Full Stack Development?

• Full Stack Development refers to the process of developing both the front end (client side) and the back end (server side) of a web application.
• This involves a comprehensive understanding of the various stages of a web application, including UI/UX, middleware, backend programming, databases, version control, and possibly more.

What Do Full Stack Web Developers Do?

Full Stack Web Developers are involved in every phase of a web application. They are jacks of all trades in the coding world. Their responsibilities include:

• Designing user interactions on web pages.
• Developing servers and databases for website functionality.
• Ensuring cross-platform optimization for mobile devices.
• Seeing out a project from conception to final product.
• Designing and developing APIs.

What Skills Do You Need to Be a Full-Stack Developer?

Becoming a Full-Stack Developer requires a multitude of skills, including but not limited to:

• Frontend Skills: Proficiency in HTML/CSS, JavaScript, and libraries or frameworks such as React, Angular, or Vue.js.

• Backend Skills: Familiarity with server-side languages like Python, Ruby, Java, or .NET, and understanding of server-side frameworks like Express.js, Django, or Ruby on Rails. There are courses for Python Training in Ahmedabad, Django training and all types of languages! Enroll in one to master the language you want to excel at.

• Databases: Knowledge of various DBMS technologies like MySQL, MongoDB, Oracle, SQLServer, etc.

• Version Control/Git: Understanding of Git, GitHub, and version control methods.

• Basic Design Ability: Knowledge of basic prototyping and UX/UI design.

• Understanding of REST and HTTP Protocol.

• Web Architecture: Ability to structure the code, separate the file, structure the data in databases, and perform complex server-client builds.

What Distinguishes The Terms Abstract And Interface?

Abstract Class

• It is a type of class in object-oriented programming.
• It is declared using the keyword 'abstract.'
• It can have methods with implementations.
• It can have both abstract and non-abstract methods.
• It can contain constructors, variables, and blocks.
• It cannot be instantiated.

Interface

• It's a blueprint of a class in object-oriented programming.
• Declared using the keyword 'interface.'
• Cannot have methods with implementations (until Java 8 introduced default and static methods).
• It can have only abstract methods.
• It cannot contain constructors, variables, or blocks.
• It cannot be instantiated.

What is Pair Programming? Explain.

• Pair Programming involves two programmers sharing a single workstation (one screen, keyboard, and mouse among the pair).
• The programmer who writes the code is called the "Driver," while the other, reviewing each line of code as it's typed in, is the "Navigator."
• The "Navigator" thinks about the big picture, spots errors, and thinks ahead.
• The two programmers switch roles often.
• It encourages teamwork, improves code quality, and promotes knowledge sharing.

Pair Programming Example

Let's consider a simple JavaScript function that calculates the sum of all numbers in an array. Here's how the process might look during pair programming.

Navigator's Suggestions

1. Suggest using a higher-order function like reduce instead of a for loop for code conciseness.
2. Check if the input is indeed an array and if it is empty.
3. Handle cases where the array includes non-numeric values.

Revised Code After Pair Programming

In the revised code, the Navigator helped the Driver enhance the function by using the reduce method, checking for input validity, and handling potential exceptions.

What Is CORS?

• CORS stands for Cross-Origin Resource Sharing.
• It is a mechanism that uses additional HTTP headers to tell browsers to give a web application running at one origin access to selected resources from a different origin.
• CORS mechanisms work by adding specific HTTP headers that tell the browser to allow web applications from one origin to access the resources at a different origin.

What Is Inversion of Control (IoC)?

• IoC is a principle in software engineering where the flow of a program is inverted. Instead of the programmer controlling the flow of a program, the external framework or runtime controls it.
• IoC is a key part of many frameworks, enabling better modularity, more straightforward testing, and higher flexibility.
• Dependency Injection is a form of IoC where implementations are passed into an object through constructors/setters/service lookups, which removes the dependency of the object to instantiate or find the particular service.

What Is Continuous Integration?

• Continuous Integration (CI) is a software development practice in which small adjustments to the underlying code base are continuously applied and tested in a shared repository.
• The goal of CI is to catch and address bugs quicker, improve software quality, and reduce validation and release time.
• Developers often use a version control system such as Git and automation servers like Jenkins, Travis CI, and CircleCI for CI.
• This practice is often part of a larger cultural approach known as DevOps, which brings together software development and IT operations.

How Is GraphQL Different from REST?

Parameter	GraphQL	REST
Data Fetching	Allows fetching exactly what you need, no more, no less. Avoids over-fetching and under-fetching.	You have to download the entire representation of a resource, which can lead to over-fetching/under-fetching.
Versioning	Avoids versioning as new fields can be added to server responses without impacting existing queries.	Often requires versioning (v1, v2, etc.) when the structure of resources changes over time.
Speed	Due to precise fetching, it can be faster, especially over slow network connections.	Can be slower due to over-fetching of data and more round trips.
Error Handling