11 Top Full-Stack Developer Interview Questions

Full Stack Web Developer Interview

Learning Front-End and Back-End Web Development technology are essential for students aspiring to pursue a career in web development. We have handpicked key questions that can be your guide to nail the technical interview rounds. 

What should a full-stack developer know?

A full-stack developer should know the following:

  • Programming languages: Proficiency in multiple programming languages like PHP, Java, C#, Ruby, Perl, Python and many more. Besides, familiarity with different ways to structure, design, implement and test the project-based on the programming languages.
  • Frameworks: Proficiency in words that are accompanied by development frameworks like Spring, JAVA, MyBatis, Python Django, PHP think PHP, Hibernate, nodeJs express, yin and more. 
  • Front-End: Advanced knowledge of necessary front-end technologies like CSS3, HTML5 and JavaScript. An additional adequate understanding of third-party libraries like jQuery, SASS, LESS, AngularJS, or REACT. 
  • Databases: Sufficient knowledge of at least one popular database like MySQL, Oracle, MongoDB, SQLServer and Redis.
  • Design Ability: Formative knowledge of the principle of prototype design, UI and UX design. 

What is the difference between GET and POST?

The primary difference between the two includes the following:

GET:

  • It is used to recover the data
  • It carries the request parameter in the URL string
  • It can be bookmarked

POST:

  • It is used for writing the data
  • Takes the request parameter in the message body
  • It cannot be bookmarked

What is RESTful API and why is it used?

A RESTful API often called RESTful web service refers to REST (Representational State Transfer) and complete kind of API is the Application Program Interface. The program the interface utilises HTTP protocol to define the set of function such as GET, PUT, POST and DELETE data.

What is the difference between MVP and MVC?

MVP is a derivation of the MVC (Model View Controller example) architectural pattern. It is used for building user interfaces. In general, the MVP pattern allows separating the presentation layer from the logic.

The difference between the two is as follows:

MVP:

  • View handles the user gestures
  • The interaction with the model is passed through the presenter
  • Provides full sport to unit testing             

MVC:

  • The controller manages the user gestures
  • The view can query the model directly
  • Provides limited support to unit testing

List key things to consider when coding with SEO in mind.

To build a site optimised for organic search engine rankings, it is important to implement certain standards throughout the code. These include:

  • Specifying an alt tag on images
  • Using the correct HTML tags for content hierarchy i.e., <h1>/<h2>/<h3> and p
  • Connect the site to the company’s social pages
  • Add an XML sitemap
  • Avoid broken links
  • Use vanity/friendly URLs (human-readable)
  • Add a robots.txt file
  • Integrate Google analytics (or alternative)
  • Specify a favicon, bonus for specifying browser-specific icons
  • Ensure lightning-fast page load time
  • Avoid JavaScript errors
  • Optimise assets (including minification)
  • Enable and force SSL
  • Specify unique titles for each page without exceeding 70 characters
  • Include a meta description on each page
  • Ensure there is enough content with enough relevant keywords (search engines will penalise your site if all pages are one-sentence pages)
  • Leverage browser caching
  • Avoid W3C markup validation errors
  • Specify relevant meta tags

How would you prevent a bot from scraping your publicly accessible API?

In this situation, if the data within the API is accessible to the public, then technically it will not be possible to entirely prevent data scraping. However, one approach that can be used to minimise to deter bots is throttling or rare limiting. It will prevent a certain device from making a definitive number of requests within a defined time.

In case exceeding the defined number of requests, a 429 Too Many Attempts HTTP error should be thrown. However, it is important to record the device with more than just an IP address as this is not unique to the device and can result in an entire network losing access to an API.

  • Blocking requests based on the user agent string (easy to circumvent)
  • Generating temporary “session” access tokens for visitors at the front end. This isn’t secure: Storing a secret on the front end can be reverse-engineered, thus allowing anyone to generate access tokens. 

What is the purpose of the Bridge Pattern?

It is used in areas that require an abstraction that needs to be decoupled from its implementation to enable the two to stand independently. The pattern is useful when the class and its functions vary. While the class is considered as an abstraction, its function is considered as implementation.

In this pattern, an interface is utilised and acts as a bridge liberating the functionality of concrete classes from interface implementer classes. Therefore, both classes can be manipulated and altered without affecting each other.

Mention the ways to optimise a website to enhance its scalability and efficiency.

Optimising website is an art known only to a few talented ones that primarily involves organic coding with instincts. The ways to optimise a website can include:

  • Optimise all assets
  • Place all assets on a separate, cookie-free domain. Using a CDN is best
  • Avoid inline JavaScript and CSS
  • Enable gzipping
  • Ensure all code is minified
  • Defer parsing of JavaScript
  • Use srcset for responsive images
  • Leverage browser caching
  • Reduce DNS lookups
  • Avoid duplicate code
  • Avoid URL redirects
  • Enable HTTP keep-alive
  • Serve scaled images
  • Use image sprites where appropriate
  • Prefer asynchronous resources
  • Specify the character set at the server level
  • Avoid CSS @import
  • Specify a cache validator
  • Minimise request size
  • Avoid bad requests and 404s
  • Specify image dimensions
  • Reduce cookie size
  • Make fewer HTTP requests, i.e., load as few external resources as possible
  • Avoid unnecessary images; where possible, use CSS
  • Ensure no validation errors with W3C

What is MEAN Stack? 

MEAN stack refers to a collection of JavaScript-based technologies that are used to design and develop web applications. MEAN is made up of four major technologies MongoDB, ExpressJS, AngularJS and Node.js.

It is a full-stack development toolkit used to develop a fast and robust web application. It is a user-friendly stack that is ideal to build dynamic websites and applications. This free and open-source stack offers a prompt and organised approach for creating rapid prototypes for web applications.  

What’s your favourite language and why?

The purpose of asking this question is simple as the interviewer want’s to understand the reasoning behind your answer and also keep you at ease. The interviewer gets to know your inclination towards technologies and languages that you are acquainted with and can evaluate you based on the answer.

Full Stack developers are required to work with dynamic sets of technologies and applications, therefore, they must be well-versed in at least two or three programming languages, including the trending languages like Java, Python, R, etc.

Not giving a blatant answer to the question and professing your knowledge on different languages stating their features can mark a promising impact about your intellect.  

What qualities should a Full Stack Developer have? 

Before answering the question, let us tell you that becoming a full-stack developer does not happen overnight and neither by learning an application instantly. To become a successful full-stack developer, you should at least have the following specialised skills.

  • Front-end technology
  • Development languages
  • Database and cache
  • Basic designing skills
  • Server skills
  • Ability to work with APIs
  • Ability to work with Version Control System (VCS)

The above-mentioned questions are quick, insightful and feature key pointers that are a significant part of the interview process. To learn full-stack web development or mean stack web development, click here.