Senior React JS Developer

ABOUT THE ROLE:

Rupeestop is a fintech platform helping people take control of their financial future. We're looking for a

React Native Developer who is sharp, hands-on, and genuinely excited about building great mobile

products. You'll work closely with product, design, and backend teams to ship polished, high-performing

apps — and own your work end to end.

We move fast, experiment often, and iterate relentlessly. You'll be expected to take full ownership, grow into

a leadership role, and bring thinking that goes beyond your assigned tasks. If you get restless when things

are too predictable — you'll fit right in.

WHAT YOU'LL DO:

- Build and maintain production-quality mobile apps for Android and iOS using React Native.

- Own features end-to-end — from design handoff through deployment on Play Store and App Store.

- Integrate REST APIs, authentication flows, push notifications, deep linking, and real-time features.

- Optimise app performance, memory usage, animations, and stability across a range of devices.

- Debug, test, and iterate — improving reliability and quality continuously.

- Use AI-assisted development tools (Cursor, Copilot, etc.) to move faster and build smarter.

- Contribute to architecture decisions and participate actively in product and team discussions.

WHAT YOU NEED:

- Strong hands-on React Native experience — including at least one app live on Play Store or App

Store.

- Solid JavaScript / TypeScript skills; comfort with modern patterns and ES standards.

- Experience with React Native CLI and native module bridging — not just Expo.

- Familiarity with state management (Redux, Zustand) and navigation (React Navigation).

- Understanding of app signing, build configs, and deployment workflows (Fastlane, EAS, etc.).

- Experience with Firebase, push notifications, background tasks, and device-level permissions.

- Ability to read or write basic native code (Kotlin/Java or Swift/Obj-C) is a strong plus.

- Comfortable with Git, pull request workflows, and working in a shared codebase.

GOOD TO HAVE:

- CI/CD experience for mobile builds (Bitrise, GitHub Actions, Fastlane).

- Knowledge of WebSockets, offline-first architecture, or real-time data sync.

- Prior experience in fintech, consumer apps, or high-traffic mobile products.

- Consistent use of AI tools as part of your daily development workflow.

WHO YOU ARE:

- You take full ownership — you don't wait to be told, you see what needs doing and do it.

- Detail-obsessed: broken UI, inconsistent spacing, and edge cases bother you.

- A natural experimenter — comfortable trying new approaches, breaking things, and fixing them.

- Adaptable: priorities shift in a startup environment, and you handle that well.

- Ready to step into a team lead role as we scale — mentor others, make decisions, drive quality.

Key Responsibilities

• Build and maintain high-quality, responsive web applications

• Collaborate with designers and product managers to translate requirements into intuitive UI/UX

• Optimize applications for performance, security, SEO, and scalability

• Write clean, maintainable, and well-documented code

• Debug, troubleshoot, and fix issues across the frontend stack

• Stay updated with the latest frontend trends and tools to improve development practices

Requirements

• 2–4 years of professional experience as a Frontend Developer

• Strong proficiency in JavaScript/TypeScript with modern frameworks like React.js/Next.js

• Experience consuming REST/GraphQL APIs

• Strong understanding of HTML5, CSS3, Tailwind/Styled Components and responsive design principles

• Knowledge of version control (Git)

• Familiarity with build tools and CI/CD pipelines

• Understanding of web performance,accessibility and SEO best practices

• Strong problem-solving and debugging skills

What is in it for you

• Very high ownership role in a fast-paced environment

• Closely work with the founder & a super passionate team of people in building Eternz

• Competitive salary commensurate

• Fast career growth & appraisals

• A dynamic and collaborative work environment- No hierarchy/Politics!

• Health insurance

Additional Details

• We are an early-stage start-up and valuable achievements take time & efforts. And hence it is a 6 day work week & we strongly believe there is no substitute for hard work & passion!

• Location: HSR layout, Bangalore

About the job

The ideal candidate will have strong creative skills and a portfolio of work that demonstrates their passion for product designing with the creativity that would produce an appealing and delightful user experience.

About the role and responsibilities

The UI/UX designer’s role encompasses a couple of the following responsibilities.

To be able to communicate and tell stories with animations

To understand, conceptualise and create storyboards for micro-animations and animations before the final animation

Working alongside UI/UX designers to enhance the experience of digital products

Frequently identify opportunities where motion design would enhance the user experience in digital solutions

Create high quality, creative and innovative animations in 2D and/or 3D

To have a keen interest in learning new tools and expand their horizon of knowledge

About the requirement

The UI/UX designer should have the following abilities

Proven motion design experience and a diverse portfolio to showcase one’s work

Strong storytelling skills and a solid foundation in the fundamentals of visual and motion design

Display the ability to work in different styles

Proficient in softwares like After Effects(presets and plugins), Photoshop, Illustrator, Figma, etc.

A keen eye for design aesthetics and details

Able to articulate ideas, both written and spoken, to drive impact

Good communication skills

Ability to work methodically and meet work in a fast-paced environment

The ability to create illustrations will be a plus

Prior experience with product company or digital products will be a plus

Degree / Certification in Design, Fine Arts or related field is a plus

•  DOT NETCore,.NET, C#,NET Core, http://asp.net/" target="_blank">ASP.NET Core Rest API, Odata,
• Blazor, HTML, CSS, Bootstrap, JavaScript,
• Development of Docker container-based microservices,
• Azure SaaS Services (Azure Service Bus, Azure Kubernetes Services, CosmosDB, Cognitive Services, Redis),
• Azure DevOps (ALM Platform),
• CI/CD delivery via Azure Pipelines,
• MS-SQL (T-SQL) and No-SQL databases (MongoDB),
• Object-Oriented Programming Principles, SOLID, Design patterns
• Good communication skill

• Minimum 3 years experience in React redux and Flux
• 3 years experience in Frontend skills
• Familiarity with database technology such as MySQL,  MongoDB. ·
• Good communication. 

• Design and code features for the website application as per the specifications provided by the Product and Design teams.
• Ship features in fast-moving agile sprints.
• Work closely with Backend, Product Design, and Product Management teams to brainstorm and chalk out details of features.
• Ability to build a feature from scratch & drive it to completion

Must have:

• Good understanding of Javascript and Clean architecture.
• Good understanding of asynchronous programming, callback, and closures.
• Strong experience with Javascript frontend framework/libraries like ReactJS
• Understanding of stateless application
• Good knowledge of CSS and its pre-processors like SASS/LESS
• Good understanding of server-side templates.
• Experience with creating cross-browser compatible web apps
• Should be Strong in MySql / Postgres database.
• Stronghold in Data structure and processing JSON

Good to have

• Basic knowledge of CI, CD
• Intermediate knowledge in any cloud services(AWS, GCP)
• Familiar with testing frameworks like Mocha, Cypress

Kvantum is a career-changing opportunity where you will get to learn the latest and greatest marketing analytics for CPG, Retail, eCommerce, Pharma industry (to name few). At Kvantum, you will be part of a rapidly growing company. You will be able to make your mark; you’ll help write the story.  You will get the chance to go above and beyond, being a hero to your clients and to your team. You will get the chance to make a big impact, applying your coding skills, domain expertise to ready the most innovative marketing science product to Fortune 1000 customers.

What you’ll be doing in your new job:

 As a  Front End/UI Developer at Kvantum you will be working with incredibly talented, optimistic people in an environment that fosters innovation builds trust, and frequently erupts into laughter. You are a natural developer and enjoy helping team members in coding and development. You command respect from your superiors and also from peers. In this role, you’ll demonstrate a proven track record of developing enterprise-grade web frontends using technologies such as JavaScript, Ajax, XHTML and JSON. You'll join a team of exponential application developers who are working hard to develop our next generation SaaS marketing applications.

 Primary Responsibilities includes:

• Develop Proof-of-Concept and prototype applications using new technologies and frameworks. In addition to collaborating with internal teams and clients to create innovative solutions.
• Help establish GUI best practices and JavaScript frameworks for web development.
• Provide context and guidance for integration and implementation of Front-End Interfaces
• Translate wireframes, comps, and functional requirements into functional HTML/ CSS / Javascript.
• Develop standards-compliant mark-up and code for web sites and applications
• Develop JavaScript using standard Frameworks (jQuery, etc.)
• Develop small to medium size custom JavaScript libraries for reuse across the application
• Provide technology and implementation expertise to the domain, projects, or client
• Maintain leading-edge knowledge in emerging technologies and frameworks
• Participate in knowledge sharing and lessons learned sessions from project experiences

For this position, you must have:

• Expert JavaScript/HTML/CSS coding skills.
• 2-4 years of professional experience 
• Minimum 2 years of relevant experience in javascript 
• Minimum 1 year of relevant experience in React.js
• Hands-on experience with the implementation of different design patterns
• Proven experience of developing software using the Agile/SCRUM development methodology
• Command of web standards, CSS based design, cross-browser compatibility
• Experience to optimize the performance of the web application;
• Good understanding of page rendering, DOM manipulation, caching, REST API
• Experience of developing the application using  Test-driven Development(TDD)
• Experience of working on LINUX environment
• Attention to detail, Dedication, and Problem-Solving skills.

Nice to Have: 

• Working experience in any of  these technologies and frameworks: D3.js, Node.js, Express.js, Elasticsearch, GraphQL, Redis
• Experience working with start-ups.
• A good learning curve for new technologies.

We provide a competitive stipend and abundant opportunity for talented people to grow faster. Our people (as we call them Kvants) know how to celebrate success (monthly team events, quarterly company events, employee awards, etc.) and work smart to achieve desired goals.

Disclaimer:

Outside Recruiters: Kvantum prefers to recruit candidates directly. We do not accept unsolicited agency resumes. Please do not contact Kvantum employees with unsolicited resumes. Any resume sent by an outside agency without an explicit signed Kvantum generated agency agreement in place will be considered unsolicited and will not be eligible for payment.

Learn from the best: Learn from leaders who have built Comm100 from ground up. Work under other engineers who handle different layers of the infrastructure.

Work in a data-driven team: Understand the importance of validating assumptions about user behaviour. Use various types of testing to ensure we're right (or discover where did we go wrong). Utilize data collection, enrichment, analytics, and visualizations to improve our systems.

WHO YOU ARE

To be successful in this role, you'll need to have the following skills:

Love for coding: A fanatic about writing beautiful and scalable code.

Sense of analytics: Strong analytical and troubleshooting skills. Should be resourceful, innovative, and inventive.

Dynamic: Should be comfortable in dealing with lots of moving pieces. Have exquisite attention to detail and are comfortable learning new technologies and systems.

Team player: Knack for influencing without being authoritative. Pitch in wherever the team needs help, from writing blog posts to supporting customers.

Accountability: High sense of ownership for your code and relentlessness to deliver projects with high business impact.

KEY SKILLS

• Strong computer system analysis and design skills in current methodologies and patterns including vanilla JavaScript,
• Rich experience with ReactJS, Redux, React Native, or similar library/tools.
• Obsessed with WPO (Web Performance Optimization) and web/mobile performance analysis.
• Familiar with web security, SEO, accessibility, and internationalization.
• Experience with W3C standards, HTTP protocol and web browsers.
• Experience with common tools such as front-end compilation, construction, testing, etc. (Babel, Rollup, Webpack, Jasmine, etc.)