
We are looking for a skilled React.js Developer to join our front-end development team. In this role, you will be responsible for developing and implementing user interface components using React.js concepts and workflows such as Redux, Flux, and Webpack. You will also be responsible for profiling and improving front-end performance and documenting our front-end codebase.
To ensure success as a React.js Developer, you should have in-depth knowledge of JavaScript and React concepts, excellent front-end coding skills, and a good understanding of progressive web applications. Ultimately, a top-class React.js Developer should be able to design and build modern user interface components to enhance application performance.
Responsibilities
- Meeting with the development team to discuss user interface ideas and applications.
- Reviewing application requirements and interface designs.
- Identifying web-based user interactions.
- Developing and implementing highly responsive user interface components using React concepts.
- Writing application interface codes using JavaScript following React.js workflows.
- Troubleshooting interface software and debugging application codes.
- Developing and implementing front-end architecture to support user interface concepts.
- Monitoring and improving front-end performance.
- Documenting application changes and developing updates.
Requirements
- Previous experience working as a React.js Developer.
- In-depth knowledge of JavaScript, CSS, HTML, and front-end languages.
- Knowledge of REACT tools including React.js, Webpack, Redux, Saga
- Experience with user interface design.
- Knowledge of performance testing frameworks including Mocha and Jest.
- Experience with browser-based debugging and performance testing software.
- Excellent troubleshooting skills.
- Good project management skills.

About Eszmeletlen Holding Co
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About One Impression
One Impression is one of the world’s largest influencer marketing platforms, working with 300+ global brands like Unilever, Nestle, and Amazon to connect with a diverse creator network. Our platform empowers brands and creators to collaborate seamlessly and scale their reach. To capture a significant share of global media ad spend, One Impression is quickly becoming the industry’s go-to influencer marketing platform.
Job Overview
We are looking for a seasoned Senior Frontend Engineer (SDE III) with over five years of experience to lead, mentor, and grow a high-performing engineering team. The ideal candidate will have extensive hands-on experience in software development, deep technical expertise, and a proven track record of successfully leading large-scale engineering teams and projects. This role requires strategic leadership, the ability to manage complex technical challenges, and the ability to drive innovation while ensuring operational excellence.
As a Frontend Lead, you will collaborate with key stakeholders across the business, product management, and operations to ensure alignment with the organization’s goals and play a critical role in shaping the technology roadmap and engineering culture.
Key Responsibilities:
- Leadership and Team Development: Lead and inspire a team of engineers, fostering a culture of innovation, accountability, and continuous improvement. Manage the hiring, training, and career development of engineering staff.
- Strategic Planning: Work closely with senior leadership to develop and implement engineering strategies that support business objectives. Define technology roadmaps and ensure alignment with organizational goals.
- Technical Excellence: Guide the team in designing and implementing scalable, robust software systems. Drive the adoption of best practices in architecture, coding standards, and software testing to ensure high-quality product delivery.
- Project and Program Management: Oversee the successful delivery of engineering projects, ensuring deadlines, quality standards, and budget constraints are met. Use agile methodologies to manage the development process and resolve bottlenecks.
- Cross-functional collaboration: Collaborate with Product Management, Design, Business, and Operations teams to define project requirements and deliverables. Ensure the smooth integration of engineering efforts across the organization.
- Risk Management: Anticipate and mitigate technical risks and roadblocks. Proactively identify areas of technical debt and drive initiatives to reduce it.
- Stakeholder Communication: Act as the technical point of contact for stakeholders, providing regular updates on project progress, resource allocation, and performance metrics. Communicate complex technical concepts to non-technical stakeholders.
Required Qualifications:
- Bachelor’s or Master’s degree in Computer Science, Information Technology, or a related field
- 5+ years of experience in software engineering.
- Proven track record of successfully delivering large-scale, high-impact software projects.
- Strong understanding of software architecture, design patterns, and scalable system design.
- Expertise in multiple programming languages and modern development frameworks. For this we require expertise in JS/React, and React Native.
- Experience working with REST APIsMust have a knack for developing good looking frontend apps.
- Experience with cloud infrastructure (AWS), microservices, and distributed systems.
- Experience in delivering full-stack B2B/SaaS applications including mobile applications, web frontend, and a scalable backend.
- Excellent problem-solving skills, with the ability to diagnose and resolve complex technical challenges.
- Strong communication and interpersonal skills, with the ability to influence and inspire teams and stakeholders at all levels.
Why Join One Impression?
- Be a part of one of the largest influencer marketing platforms globally, working with top brands and influencers.
- Opportunity to lead and shape a fast-growing marketplace product.
- Competitive salary and benefits package.
- A collaborative and innovative work culture in a rapidly scaling company.


Avegen is a digital healthcare company empowering individuals to take control of their health and supporting healthcare professionals in delivering life-changing care. Avegen’s core product, HealthMachine®, is a cloud-hosted, next-generation digital healthcare engine for pioneers in digital healthcare, including healthcare providers and pharmaceutical companies, to deploy high-quality robust digital care solutions efficiently and effectively. We are ISO27001, ISO13485, and Cyber Essentials certified; and compliant with the NHS Data Protection Toolkit and GDPR.
Job Summary:
Senior Software Engineer will be responsible for developing, designing, and maintaining the core framework of mobile applications for our platform. This includes tasks such as creating and implementing new features, troubleshooting and debugging any issues, optimizing the performance of the app, collaborating with cross-functional teams, and staying current with the latest advancements in React Native and mobile app development. We are looking for exceptional candidates who have an in-depth understanding of React, JavaScript, and TypeScript, can create pixel-perfect UI, and are obsessed with creating the best experiences for end users.
Your responsibilities include:
- Architect and build performant mobile applications on both iOS and Android platforms using React Native.
- Work with managers to provide technical consultation and assist in defining the scope and sizing of work.
- Maintain compliance with standards such as ISO 27001, ISO 13485, and Cyber Essentials that Avegen adheres to.
- Lead configuration of our platform HealthMachine™ in line with functional specifications and development of platform modules with a focus on quality and performance.
- Write well-documented, clean Javascript/TypeScript code to build reusable components in the platform.
- Maintain code, write automated tests, and assist DevOps in CI/CD to ensure the product is of the highest quality.
- Lead by example in best practices for software design and quality. You will stay current with tools and technologies to seek out the best needed for the job.
- Train team members on software design principles and emerging technologies by taking regular engineering workshops.
Requirements:
- Hands-on experience working in a product company developing consumer-facing mobile apps that are deployed and currently in use in production. He/she must have at least 3 mobile apps live in the Apple App Store/Google Play Store.
- Proven ability to mentor junior engineers to realize a delivery goal.
- Solid attention to detail, problem-solving, and analytical skills & excellent troubleshooting skills.
- In-depth understanding of React and its ecosystem with the latest features.
- Experience in writing modular, reusable custom JavaScript/TypeScript modules that scale well for high-volume applications.
- Strong familiarity with native development tools such as Xcode and Android Studio.
- A positive, “can do” attitude who isn’t afraid to lead the complex React Native implementations.
- Experience in building mobile apps with intensive server communication (REST APIs, GraphQL, WebSockets, etc.).
- Self-starter, able to work in a fast-paced, deadline-driven environment with multiple priorities.
- Excellent command of version control systems like Git.
- Working in Agile/SCRUM methodology, understanding of the application life cycle, and experience working on project management tools like Atlassian JIRA.
- Good command of the Unix operating system and understanding of cloud computing platforms like AWS, GCP, Azure, etc.
- Hands-on experience in database technologies including RDBMS and NoSQL and a firm grasp of data models and ER diagrams.
- Open source contributions and experience developing your own React Native wrappers for native functionality is a plus.
Qualification:
BE/BTech/MS in Information Technology, Computer Science, or a related discipline.

Job Description
- Experience in UI development using React JS
- In depth knowledge of JavaScript, CSS, HTML and front-end languages
- Excellent front-end coding skills, and a good understanding of progressive applications
- Strong knowledge of UI design principles, patterns, and best practices
- Experience working with JavaScript and Typescript, React, Redux, RxJS, Yarn
- Experience in test driven development using modern source control and continuous integration
- Design, develop, test, deploy and maintain software
- Delivering high quality and well-structured code

About Optiblack LLC
Optiblack LLC is a company that specializes in providing tech and analytics services. We offer a range of solutions to help businesses meet their goals, including:
- Data Analytics: we can help you extract insights from your data to make informed decisions.
- Web Development: we can design and build custom websites for your business.
- Mobile App Development: we can create mobile apps for both iOS and Android platforms.
- AI and Machine Learning: we can leverage these technologies to automate tasks and improve efficiency.
Optiblack LLC has a team of experienced professionals who can help you with your project. They have a track record of success in delivering high-quality solutions to our clients.
About the Role
We are looking for a passionate and talented intern developer to join our growing team at Optiblack LLC. This is a fantastic opportunity to gain hands-on experience building and maintaining our React Native mobile application. You will work alongside experienced developers and contribute to a product used by millions of users.
Responsibilities:
- Develop new features and functionalities for our React Native mobile application.
- Collaborate with designers and backend developers to ensure a seamless user experience.
- Write clean, maintainable, and well-documented code.
- Fix bugs and identify areas for improvement in the existing codebase.
- Stay up-to-date with the latest trends and technologies in React Native development.
- Participate in code reviews and provide constructive feedback.
Qualifications:
- Strong understanding of React Native development concepts.
- Experience with JavaScript (ES6+) and related frameworks.
- Familiarity with React development principles is a plus.
- Experience with Git version control system.
- Excellent problem-solving and debugging skills.
- Ability to work independently and as part of a team.
- Strong communication and interpersonal skills.
- A passion for learning and staying updated with the latest technologies.
Bonus Points:
- Experience with building cross-platform mobile applications.
- Experience with UI/UX design principles.
- Experience with unit testing frameworks like Jest or Mocha.
- Experience working on Social Media Apps or having an interest in working on them.
** Internship Duration:** 3 Months
Location: Remote
To Apply:
Please submit your resume and a cover letter explaining your interest in the position and why you think you would be a good fit for our team

We are looking for a great JavaScript developer who is proficient with React.js. Your primary focus will be on developing user interface components and implementing them following well-known React.js workflows (such as Flux or Redux). You will ensure that these components and the overall application are robust and easy to maintain. You will coordinate with the rest of the team working on different layers of the infrastructure. Therefore, a commitment to collaborative problem solving, sophisticated design, and quality product is important.
Responsibilities
-
Developing new user-facing features using React.js
-
Building reusable components and front-end libraries for future use
-
Translating designs and wireframes into high quality code
-
Optimizing components for maximum performance across a vast array of web-capable devices and browsers
Skills
-
Strong proficiency in JavaScript, including DOM manipulation and the JavaScript object model
-
Thorough understanding of React.js and its core principles
-
Experience with popular React.js workflows (such as Flux or Redux)
-
Familiarity with newer specifications of EcmaScript
-
Experience with data structure libraries (e.g., Immutable.js)
-
Knowledge of isomorphic React is a plus
-
Familiarity with RESTful APIs
-
Knowledge of modern authorization mechanisms, such as JSON Web Token
-
Familiarity with modern front-end build pipelines and tools

React Components/ Highly responsive well user interface.
Develop a flexible and well structured, along with the API's
Candidate must have good skills in
HTML/CSS
JavaScript
jQuery
JavaScript Frameworks
Front End Frameworks
CSS Preprocessors
RESTful Services/APIs
Responsive/Mobile Design
Cross-Browser Development
Content Management Systems

- Develop new user-facing features
- Build reusable code and libraries for future use
- Ensure the technical feasibility of UI/UX designs
- Optimize application for maximum speed and scalability
- Assure that all user input is validated before submitting to the backend
- Collaborate with other team members and stakeholders
Skills And Qualifications
- Proficient understanding of web markup, including HTML5, CSS3
- Basic understanding of server-side CSS pre-processing platforms, such as LESS and SASS
- Proficient understanding of client-side scripting and JavaScript frameworks, including jQuery
- Good understanding of advanced JavaScript libraries and ReactJS frameworks.
- Good understanding of asynchronous request handling, partial page updates, and AJAX
- Basic knowledge of image authoring tools, to be able to crop, resize, or perform small adjustments on an image. Familiarity with tools such as Gimp or Photoshop is a plus.
- Proficient understanding of cross-browser compatibility issues and ways to work around them.
- Proficient understanding of code versioning tools, such as Git / Mercurial / SVN.
- Self-motivated and a good team player.
- Good communication and interpersonal skills.
- Preferred years of experience- 2- 3 years
- Bachelor’s Degree in Engineering from a reputed Institute.

1. Core Java.
2. Thorough understanding of React.js and its core principles.
3. Strong proficiency in JavaScript, JQUERY, including DOM manipulation and the JavaScript
object model.
4. Experience with popular React.js workflows (such as Flux or Redux).
5. Knowledge of modern authorization mechanisms, such as JSON Web Token, SSO
authentication.
6. Familiarity with RESTful APIs.
7. Familiar with Linux
8. Experience with common front-end development tools such as Babel, Webpack, NPM, etc.
9. Familiarity with Spring Boot, Hibernate (JPA)
10. Oracle or any other DB experience
11. Any J2EE server or Tomcat container experience required


- We are looking for techies with a passion to develop high-performance web applications.
- If you are interested and looking to build scalable and high-performance apps, then join us. We are building web app based on React with server-side rendering. For mobile, we are building PWA.
Roles & Responsibilities :
1. Build scalable web applications using ReactJS, Redux and other related libraries.
2. Integrating back-end API's with front-end.
3. Build reusable code and libraries for future use.
4. Optimize application performance and reduce page loading speed.
5. Solid experience in architecting and implementing highly scalable front-ends in modern technologies such as React or Vue.
6. Gathering requirements from design and technical staff and client on web development needs/Defining effective solutions for business and process problems.



- Ability to design the overall architecture of UI components of the web application.
- Maintain quality and ensure responsiveness of applications.
- Collaborate with the rest of the engineering team to design and launch new features.
- Maintain code integrity and organization.
- Experience working with graphic designers and converting designs to visual elements using JavaScript, HTML, and CSS.
- Understanding and implementation of security and data protection.
- Good problem-solving skills and willingness to learn new technology
Qualifications:-
- 2+ year track record of relevant work experience and a Computer Science or a related technical discipline is required
- Excellent knowledge of JavaScript
- Proficient experience in ReactJS.
- OOPS, Concept, and Data Structure like Queue, Stack, Tree, Linked List, etc.
- Good knowledge in working with REST APIs
- Knowledge of converting designs to working web pages using HTML and CSS.
- Experience in Architecture and delivery of web applications.
- Knowledge of code versioning tool – Git
Good to have:
- Experience in AngularJS
- Experience in server-side programming

