Hire Only Senior
React Developers

Roles and responsibilities of a senior ReactJS developer

Senior ReactJS developers are front-end JavaScript developers responsible for creating and maintaining UIs for web apps and websites. Front-end development describes software development that affects what the user sees and interacts with.

On the more technical side, senior ReactJS developers have the knowledge and expertise to handle complex front-end challenges and come up with production-grade solutions.

When it comes to soft skills, senior ReactJs developers should be ready to mentor their mid-level teammates while balancing their day-to-day work. They are expected to be strong communicators as well as thoughtful and consistent collaborators.

The first step in how to hire a senior ReactJS developer is making sure your potential hires have a proficient grasp of React's deeper technical gotchas and what's required of them for front-end development in general.

The day-to-day activities of a senior ReactJS developer can be quite diverse. Here's a snippet of what you might expect.

• Developing responsive interactive technology for dynamic web pages such as menu buttons, online forms, gesture-driven actions, etc.

• Testing and debugging interface software before the application goes live.

• Working with the client to better understand how to manifest their vision for the app via software development.

  Consulting with back-end engineers and developers to ensure that collaborative user-facing and server-side interactions run without error

The State of JavaScript Survey shows that React places highly for both usage and satisfaction.

Skills to look for in a senior ReactJS developer

To hire the best senior ReactJS developers, you'll need to evaluate them for various front-end-specific skills.

Attention to detail

There's nothing more frustrating than a front-end developer who can't translate a design into a pixel-perfect user interface. No matter how well the front end is built, if it just doesn't look good, you can guarantee that you will drive away users.

You'll want to look for developers who take pride in building interfaces that honor the craft and detail designers put into the UI. Components are designed at the proper ratios and micro-interactions are discussed and developed with care.

State management using Redux and Hooks

Developers must know how to build dynamic user interfaces that respond to interaction and facilitate proper data flow between components. This is done primarily through the use of Hooks and Redux. Regardless of the approach, it's crucial to understand state management in order to build scalable React JS applications.

Familiarity with Node.js

Knowledge of Node.js is not required for senior ReactJS developers however it's good to have some familiarity with Node.js to improve load times through server-side rendering and build more robust React.js applications.

Proficiency in ES6

While senior ReactJS developers should already know JavaScript and even TypeScript, they most certainly should be comfortable with ES6, specifically using high-order functions and making use of destructuring to write cleaner and clearer code.

How much does it cost to hire a senior ReactJS developer

In the United States, the average salary for a React developer across all industries is around $108,175 or $52 an hour. This data was collected from ZipRecruiter which compiles information from employer job postings and other third-party sources.

Senior React developers in the United States can make upwards of $163,000 a year and beyond if they are working in big tech or Silicon Valley. This is due to the costs of living and resources that these companies have.

Many tech companies look to nearshore and offshore countries to find React developers at a lower rate. Outsourcing can be a convenient way for small and medium-sized companies (SMBs) to meet their needs while reducing operating expenditures.

Senior developers who are based in Latin America, for instance, make about $100,000. While this is a great value considering the cost of living in South America, this is relatively inexpensive compared to developer rates in the United States. Again, the cost of living and market economics play a big role here.

Writing the best job description to hire senior ReactJS developers

The best job descriptions are straightforward with relevant details that allow candidates to validate themselves against what you're looking for. You can use the following guidelines when building your own job description to hire senior ReactJS developers.

• Must-haves and nice-to-haves: Be specific about the technologies and technical skills you're looking for and what types of skills or experience you believe are nice to have for candidates to land on the shortlist.

• Responsibilities: Every company has a different definition of senior or mid-level and the responsibilities that come with it based on their company size and complexity. Be clear about what their individual responsibilities will be in their day-to-day work.

• What to expect in X-months: Be upfront about what you'll expect from newly hired developers in 1 month, 3 months, and 6 months. Make sure that it's reasonable.

• Interview process: If you have an interview process, be transparent about it so that you can reduce candidate attrition.

• Strong communication: Underrated but never understated, communication makes or breaks most developers' relationships with the teams that they work with. Better to make it explicit to candidates that communication means everything to your team and without it, they will not last long.

Interview questions to hire senior ReactJS developers

With a quality job description, you'll be spending a lot of time screening and interviewing candidates. This is the most time-intensive part of the hiring process and also the most crucial.

Everyone has their own approach to interviewing candidates, and we have ours as well. Over time, the conventions have changed based on feedback from the engineering community and also the experiences gained interviewing over 30,000 developers.

Technical interview modalities change depending on the company. Teams with high standards strongly emphasize data structure, algorithms, and systems design/knowledge questions. Others might focus more on practical knowledge with specific technologies and frameworks.

When it comes to soft skills or cultural fit, the questions that companies will ask will also vary greatly. Some will take an analytical/technical approach, while others will ask questions that are intuitive for them.

There's no right or wrong, only strong or weak signals.

In this section, we'll focus specifically on technical questions geared towards senior ReactJS developers, for a more comprehensive deep-dive on soft-skills interviews check out the guide here.

Keep in mind that a candidate's ability to answer questions does not deliver strong signals about their overall ability to perform well on your team. It simply shows you that they might be able to code their way out of a paper bag with the technology you testing for.

Advanced react.js concepts

Is there a way to cancel an API request inside a useEffect?

Yes, there is a way to do this by using AbortController:

              
  useEffect(() => {
    const controller = new AbortController();
    const signal = controller.signal;
                
    fetch('your-api-url', { signal })
      .then(res => res.json())
      .then(res => setData(res))
      .catch(error => {
        if (error.name !== 'AbortError') {
          console.error(error.message);
        }
      }
    );

    return () => controller.abort();
  }, []);
              
            

The following code doesn't preserve the component state when isFavorite changes, how can you prevent/fix this?

              
  import { useState } from 'react';

  export default function App() {
    const [isFavorite, setIsFavorite] = useState(false);
    
    if (isFavorite) {
      return (
        <div>
          <Component isFavorite={true} />
        </div>
      );
    }

    return (
      <div>
        <Component isFavorite={false} />
      </div>
    );
  }

  function Component({ isFavorite }) {
    const [number, setNumber] = useState(0);

    let className = 'number';
    
    if (isFavorite) {
      className += ' isFavorite';
    }
    return (
      <div className={className}>
        <button onClick={() => setNumber(number + 1)}>
          +
        </button>
      </div>
    );
  }
              
            

When a component is rendered, the state is preserved as long as it's still in the UI tree. Issues can occur if the component is unmounted and then remounted somewhere else in the tree, and the state will be lost.

To prevent this, render the component within the same parent div to ensure that the state is preserved even if moved around in the UI tree. This way, the component can be safely unmounted and remounted without losing its state.

              
export default function App() {
  const [isFavorite, setIsFavorite] = useState(false);
  
  return (
    <div>
      <Component isFavorite={isFavorite} />
    </div>
  );
}
              
            

For more interview questions for senior ReactJS developers, check out our Interview Questions page.

Why use ReactJS in your application

The user interface is the center point of an end user's experience with an app.

Whether it's a web or mobile application, which visual library you use to power it is important. It's been an age-old debate for years, React vs. Angular vs. Vue, with companies using one or the other.

According to the numbers, the battle for superiority has already been won by React. Let's figure out why by breaking down a few of the advantages of React.js so you can determine whether or not you want to implement it as your new front-end technology.

ReactJS is a visual library for JavaScript created by Facebook to power UI's that are reactive and reflective of each user's individual experience within an app.

Designed to accommodate apps that are highly personalized experiences, it makes complete sense that a company like Facebook which owns some of the largest personalized social networks and communication tools would create something like React.

By dynamically changing the app's UI based on the data that a user inputs, React JS stands out as the ideal choice as a visual library for your project if it has functions and features such as user profiles, curated content, or customizable interfaces.

The way React prioritizes dynamic experiences makes it stand out as an ideal choice if User-Experience (UX) is something you are trying to prioritize with your app.

UX is increasingly becoming one of those things that make or break your app in an industry as competitive as tech, so considering it heavily during your development is vital.

ReactJS has been noted for being a lot more user-friendly from a development angle. It utilizes a Virtual DOM as opposed to a Real DOM, making updating apps and testing performance a lot more approachable for developers.

By making it easy to reuse code in different parts of your development environment, user interfaces can be designed and programmed in a way that favors quick-development, saving lots of time for other aspects of development.

The way React.js is designed allows it to be much more stable than other visual libraries, removing many of the headaches from front-end development.

The ability to quickly deploy dynamic user interfaces in a way that considers both the end-user and developers makes React.js a well-rounded choice for powering your front-end development.

Hire senior ReactJS Developers - Final Thoughts

Hiring senior ReactJS developers isn't easy and will take a considerable amount of your time. Time is not a luxury and as an engineering leader, you will most likely need to balance your work week between optimizing processes and hiring. That type of context switching is not recommended when better alternatives exist to find talent.

More importantly, making the wrong hire is expensive both in time and cost.

To offload the hiring process, rapidly speed up your time-to-hire, and mitigate risk, reach out to us at Trio . Our 3-step interview process was designed specifically to capture senior-level technical and soft-skill signals and hire the right senior ReactJS developers for your team.

With Trio, you can focus on what you love most - deliver great products while we handpick and shortlist from our pre-vetted talent network. We'll enable payroll, benefits, taxes, and local compliance and support you with onboarding and long-term talent management.

Happy hiring! :)