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ReactJS freelance developer
Rishabh is a software engineer having 7+ years of experience in designing front-end web applications and is expertised in web development.
Mahesh is a software engineer having 3+ years of experience in developing dynamic single page web applications and mobile apps using ReactJS and NodeJS.
Part-time React freelancer
John is a software engineer having 10+ years of experience working with ReactJS. He is experienced working on Single Page Applications and designing web applications with React.
Hire dedicated freelance ReactJS developers with UltraGenius
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Want to hire freelance ReactJS developers on your own? Here are the skills you must look for while hiring a ReactJS developer
If you are looking for a high-demand but difficult skill to develop interactive front-end, ReactJS is one of the most demanded skills. However, hiring the best and brightest freelance ReactJS developers can be challenging even if you have all the necessary skills. That’s why UltraGenius provides its expertise in helping manage your recruitment process while getting only top talent with in-depth knowledge of software development.
The following skills you must look for while hiring a freelance React developer:
- Variables and scoping
- Arrays and object
- Array methods
- Functions and arrow functions
- DOM Manipulation and event handler
- The “this” keyword
- The “class” keyword
- Prototype chain and object creation
- Higher order functions and callback functions
Conversant with JS build tools
While working with React, webpack and npm are essential tools. You will also need to know how to use yarn and have a basic understanding of webpack .
Experience with testing frameworks and tools
Rising quick-deployment needs during the development phase, testing has become an important skill for React developers. Therefore, the developers should know about Jest, Enzyme, Mocha, Chai, AVA(), and Tape for unit testing. For end-to-end testing, they must know about Selenium (webdriver), Webdriver (chromeDriver), Cypress (cypressDriver), Nightwatch (nightwatch Driver), Puppeteer (), and Karma ().
Familiarity with Version Control System (VCS)
Developers must have a very good knowledge of version control systems, like Git and SVN. Mostly, developers use Git for their work. This system helps the team collaborate and organize your code by helping them keep track of frequent changes that happen in it as well as managing the commit history. Additionally, using branches, commits, and merging allows developers to work independently on the code without any problems..
Knowledge of MVC architecture
React developers must know about Model-View-Controller (MVC) architecture. MVC approach helps you to create applications that separate the input logic, business logic, and UI logic while maintaining the loose coupling between the elements.
Experience developing RESTful API(s)
A developer must know what REST – API(s) that are used in HTTP requests using GET, PUT, POST, and DELETE methods, which enable developers to read the web application more clearly and use it effectively.
Experience with web markup and UI, UX Concepts
The developer must have a firm understanding of element positioning, displaying the elements, and making components interactive. In addition, they must be experienced with other UX concepts related to presentational markup like how headings are displayed, text is larger and put emphasis on it, captions can be included in items within table cells, etc.
Experience working with ReactJS workflows
Very important point : State management in React.js is the biggest challenge developers face while dealing with the large applications. Look for the developers who have worked with projects where they have managed states across multiple components and optimized application performance.
Check if they have worked with the popular libraries like Redux, Mobx, and Context APIs.
Proficient in writing optimized and readable code
You must hire the developers based on their ability to write clean and optimized code that is understandable by all the team members, and is scalable.
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Top Interview Questions to ask while hiring a freelance React.js developer
React DOM is slow as compared to Virtual DOM. React DOM can directly update HTML while Virtual DOM doesn't directly update HTML. Real DOM creates a new DOM if the element updates while Virtual DOM updates the JSX if the element updates. Real DOM manipulation is very expensive while Virtual DOM manipulation is very easy.
The virtual DOM is a programming concept where a virtual representation of UI is kept in memory and synced with the real DOM with the help of a library like ReactDOM. This process is called "Reconciliation".
Whenever any data is changed in UI, the changes are rendered in Virtual DOM first, then Virtual DOM is compared with Real DOM, the Real DOM will be updated only with the things that have been changed.
React lets you use state and other React features without writing a class. It makes logic and UI separable easily. To change a functional component into a class component requires a little bit of refactoring, but with React hooks functional components have the capability of tapping into the state, so that the refactoring effort will be minimal.
The lifecycle of the component consists of four phases -
- Initialization - The constructor() method is called before anything else when the component is initiated and sets up the initial state and other initial values. This method is called when your component is created but is not added to the DOM. Its main use is to initialize the state and bind this for component methods.
- Mounting - The component is added to the React DOM. Mounting includes the following methods like constructor(), getDerivedStateFromProps(), render(), and componentDidMount().
- Updating - The component receives changed props or states and is called when the components is re-rendered. Updating the component includes shouldComponentUpdate (), componentWillUpdate (), componentDidUpdate () methods.
- Unmounting - The component is removed from the React DOM. It includes the method componentWillUnmount().
Far far away, behind the word
- React increases the efficiency of an app by using Virtual DOM
React uses Virtual DOM which is the virtual representation of the Real DOM, each time when the data changes in a React application, a new Virtual DOM is created instead of reloading the page every time.
- Embedded JSX Feature
- SEO-friendly User Interface
React enables developers to develop engaging user interfaces that can be easily directed in search engines. React also allows server-side rendering, which improves the SEO of an application.
- Components are reusable
For developing applications, React uses component-based architecture. Components are independent and can be shared across various applications having similar functionality. The re-use of functionality enables developers to quickly design pages.
Props stand for Properties in React. Props are the read-only components generally used to render dynamically generated data. Props are passed in the functions as similar as the arguments are passed. Props are always sent from parent to child component and never vice-versa.
- Props are immutable while the States are mutable.
- Props allow you to pass information from one component to another in the argument form, while a State doesn't pass but holds the information about the components.
- Props make a component reusable by passing it to the child component while States do not have any functionality like this.
- Props are external and are controlled by whatever renders the component while the State is internal and is controlled by the React Component itself.
- Props are used to communicate between the components, States can be used for rendering dynamic changes with the component.
Each component must have a render() method. The render method returns a single React element which is the representation of the native DOM component.
To render more than one element, they must be grouped and enclosed inside the elements.
Frequently Asked Questions
UltraGenius is one of the leading platforms for hiring remote talent and connecting freelance and part-time developers with Silicon Valley businesses. We focus on finding the best talents who will perform extremely well and will be easily integrated into your teams. We filter out only the top 1% most skilled freelance developers among the 20K+ developers who have applied on our platform. Candidates have to prove their self-reported experience by giving UltraGenius’ s skill tests.
UltraGenius first tests the developer’s skill set by conducting a two and half hour hiring test. Our hiring test judges a candidate on all aspects like aptitude, case study analysis, verbal and reasoning, coding questions based on data structures and algorithms, software engineering, system design, and more. Then, there is another round for the candidates who are selected from this round called “Higher-level Assessment Skill Test”, which is a video round that deeply analyzes freelance developers’ major skills and asks questions about the projects they have worked upon.
Fill up the form which is on every hiring freelancers’ page and we will inform you once we select the top 1% freelance React.js developers matching your job requirements. After analyzing the candidates based on their resumes and two assessment tests, we provide you the feedback quickly. And if the freelancers selected by our team are fit for your job role, then we also provide the onboarding.
UltraGenius offers you only the most skilled freelance developers who are top 1% among the 20K+ freelance developers who have applied on our platform. After a rigorous selection and testing process, we sort out only the top candidates for you. You can check out UltraGenius’ s selection process for hiring freelance React developers on http://www.ultragenius.club/hire-react-freelancer.