Frontend Developer Startup Jobs in Elizabeth, NJ

About Merciv
Merciv is an AI and data analytics startup dedicated to reshaping how businesses approach strategic intelligence. Our mission is to transform how organizations harness data, generate insights, and drive strategic decisions through cutting-edge AI pipelines and dynamic forecasting mechanisms.
We're building toward a world where every business decision is informed by the right data at the right time, combining AI capability with human judgement. Our technology:

• Connects disparate data sources into a single, coherent intelligence layer
• Augments human decision-making with autonomous AI analysis
• Surfaces insights and opportunities that traditional tools miss
• Forecasts outcomes and helps teams navigate uncertainty with real clarity
• Gives organizations the ability to shape their markets, not just react to them

We're building solutions that are robust and scalable but also genuinely intuitive, so that teams across an organization can actually use them, not just the data team. We've raised $14M in seed funding, built our team around a strong engineering culture, and are launching publicly after nearly two years in stealth mode.
About the Team
We're building an agentic AI platform that's changing how enterprises work with data. Merciv connects an organization's entire data landscape with external sources - social media trends, industry reports, consumer behavior signals - to surface insights and automate workflows that used to take analysts weeks.
We care a lot about making powerful tools feel simple. Every feature should be intuitive, every component interactive. We want users to open Merciv and immediately feel like they can do more than they could before.
Our lean, agile team thrives on innovation and autonomy. We're small enough that everyone has real ownership. We use a DRI (Directly Responsible Individual) model - you'll own major product features from conception to launch, not just contribute to them. You'll wear multiple hats, and that's by design.
Our work environment thrives on creativity and cutting-edge technology, built for those eager to shape the future of human-AI collaboration. If you're excited about being a part of a fast-paced, innovative startup culture and making a significant impact on client business, Merciv is the place for you. Join us as we expand the horizons of retail intelligence and deliver unparalleled value to our clients.
The Role
Merciv is transforming how brands understand consumers through autonomous AI that doesn't just analyze data - it proactively surfaces insights that drive million-dollar decisions. Our platform powers some of the largest retail and consumer goods organizations in the world, synthesizing signals from thousands of sources to reveal patterns and opportunities before competitors see them coming.
As we scale our enterprise platform and launch our self-serve tier, we need a Senior Frontend Engineer who can craft exceptional user experiences that make complex AI-powered insights feel intuitive and actionable. This is your chance to build the interface that puts autonomous consumer intelligence into the hands of brand leaders, researchers, and marketers.
You'll own critical parts of our frontend architecture, building the UI that enables users to explore millions of data points, understand nuanced consumer sentiment, and make confident decisions backed by AI reasoning. Working closely with our product, design, and AI teams, you'll create elegant experiences that transform dense analytical outputs into clear, compelling narratives.
This is a hands-on role where you'll build the interactive components that enterprise brands rely on daily to stay ahead of market shifts. In this role, you'll be the architect of experiences that must be enterprise-grade (fast, accessible, secure) while maintaining startup agility. Your work directly impacts whether a brand leader can understand a critical consumer trend in seconds or gets lost in data - a difference measured in millions of dollars of opportunity.
What You'll Do
Build Exceptional User Experiences: Design and implement elegant, high-performance React components that make complex AI insights feel simple and actionable
Architect for Scale: Own critical parts of our frontend architecture as we grow from hundreds to thousands of daily active users across Fortune 500 enterprises
Collaborate Cross-Functionally: Partner with product managers, designers, and AI engineers to translate sophisticated analytical outputs into intuitive visualizations and workflows
Drive Frontend Excellence: Establish coding standards, conduct rigorous code reviews, and mentor team members on modern frontend best practices
Optimize Performance: Ensure sub-second load times and smooth interactions even when rendering complex data visualizations and real-time updates
Champion User-Centric Design: Work closely with UX/UI designers to implement pixel-perfect designs while advocating for usability and accessibility
Own Feature Development: Take features from concept to production, including requirements gathering, technical design, implementation, testing, and deployment
Enable AI Interaction: Build innovative interfaces for users to interact with agentic AI systems, including natural language inputs, conversational flows, and transparent reasoning displays
Ensure Quality & Reliability: Write comprehensive tests, debug across browsers and devices, and maintain high code quality standards for enterprise customers
Shape Product Direction: Contribute to product strategy discussions, bringing frontend expertise to inform what we build and how we build it
Core Requirements
Experience

• 6-10+ years of professional frontend development experience
• 4+ years building complex, production web applications with modern JavaScript frameworks
• 2+ years with React in production environments
• Experience working in fast-paced startup or high-growth product environments
• Track record of owning significant frontend features end-to-end

Technical Skills
Frontend Fundamentals

• Expert-level knowledge of HTML5, CSS3, and modern JavaScript (ES6+)
• Deep understanding of TypeScript and type-safe development practices
• Strong command of responsive design principles and cross-browser compatibility
• Expertise in web performance optimization techniques (lazy loading, code splitting, caching)

React Ecosystem

• Advanced React proficiency including hooks, context, and component lifecycle
• Experience with state management solutions (Redux, Zustand, or similar)
• Knowledge of React ecosystem tools (React Router, React Query, etc.)
• Understanding of React performance optimization and rendering patterns

Modern Development Practices

• Strong expertise in modern CSS approaches (CSS Modules, Styled Components, Tailwind, or similar)
• Proficient with build tools and bundlers (Vite, Webpack, or similar)
• Experience with version control (Git) and collaborative development workflows
• Familiarity with CI/CD pipelines and automated testing frameworks

API Integration & Data Handling

• Experience integrating RESTful APIs and GraphQL endpoints
• Understanding of asynchronous JavaScript and promise-based workflows
• Ability to handle complex data transformations and state management
• Experience with WebSocket or real-time data streaming

Testing & Quality

• Proficiency with testing frameworks (Jest, React Testing Library, Cypress, or similar)
• Experience writing unit, integration, and end-to-end tests
• Understanding of test-driven development practices
• Strong debugging skills across browsers and devices

Data Visualization

• Experience building interactive data visualizations (D3.js, Recharts, Chart.js, or similar)
• Ability to translate complex datasets into clear, compelling visual stories
• Understanding of visualization best practices and accessibility

Professional Qualities
Ownership Mentality: Track record of taking full ownership of features and seeing them through to successful production deployment
Product Thinking: Strong product sense with ability to balance technical constraints with user needs and business objectives
Clear Communicator: Excellent written and verbal communication skills; comfortable explaining technical concepts to non-technical stakeholders
Collaborative Spirit: Thrives in cross-functional environments, working closely with designers, product managers, and backend engineers
Detail-Oriented: Obsessive attention to detail in implementation, from pixel-perfect designs to edge case handling
User Advocate: Passionate about building experiences that users love; consistently thinks from the user's perspective
Strategic Thinker: Ability to balance immediate feature delivery with long-term architectural decisions
Growth Mindset: Continuous learner who stays current with frontend technologies and best practices; eager to experiment with new tools
Pragmatic Problem Solver: Strong debugging and problem-solving skills; comfortable working through ambiguous requirements
Quality Champion: Committed to writing clean, maintainable, well-documented code that your teammates will thank you for
The Frontend Challenge
At Merciv, you'll tackle unique challenges at the intersection of AI, data visualization, and enterprise UX:
Complex Data Visualization: Transform millions of consumer signals into intuitive, interactive visualizations that reveal patterns and insights at a glance
AI Transparency: Build interfaces that make AI reasoning transparent and trustworthy, showing users exactly how conclusions were reached
Real-Time Intelligence: Handle streaming updates and real-time data while maintaining smooth, responsive user experiences
Information Density: Balance information density with clarity - users need comprehensive insights without cognitive overload
Diverse User Personas: Design for everyone from Fortune 500 executives needing high-level summaries to analysts requiring deep-dive capabilities
Performance at Scale: Ensure instant load times and smooth interactions even with complex datasets and visualizations
Enterprise Standards: Meet accessibility (WCAG), security, and compliance requirements expected by Fortune 500 customers
Rapid Innovation: Ship new features quickly while maintaining code quality and user experience consistency
Nice-to-Have Skills

• Experience building data-intensive or analytics-focused applications
• Familiarity with AI/ML user interfaces or conversational UI patterns
• Background in design systems and component library development
• Experience with Next.js or other React meta-frameworks
• Knowledge of backend technologies (Node.js, Python) for better full-stack collaboration
• Experience with Figma or other design tools for design-development collaboration
• Familiarity with accessibility best practices and ARIA standards
• Experience with micro-frontend architectures or module federation
• Understanding of WebGL or advanced graphics for data visualization
• Background in consumer research, market intelligence, or retail/CPG domains
• Experience with A/B testing frameworks and feature flag systems
• Knowledge of web analytics and user behavior tracking
• Experience scaling frontend applications from early-stage to enterprise

What We're Looking For
Craftsperson Mindset: You take pride in writing beautiful, maintainable code and building polished user experiences
Initiative & Drive: You don't wait to be told what to do; you see problems and solve them proactively
User Empathy: You deeply understand that behind every click is a person trying to accomplish something important
Technical Curiosity: You stay excited about new frontend technologies and love learning from teammates
Bias Toward Action: You move quickly, iterate based on feedback, and aren't afraid to ship and learn
Humility & Collaboration: You value diverse perspectives, give and receive feedback gracefully, and elevate your teammates
Business Awareness: You understand how your work connects to business outcomes and customer value
Adaptability: You thrive in ambiguity and can pivot quickly as priorities evolve in a fast-growing startup
Systems Thinking: You consider long-term implications of technical decisions while delivering short-term value
Why Join Us?
Revolutionary Impact: Build the interface for AI that's transforming how Fortune 500 brands understand and respond to their consumers
Cutting-Edge Technology: Work with modern frontend stack, AI-powered features, and complex data visualization challenges
Enterprise Trust: Your work enables major brands to make million-dollar decisions with confidence
Rapid Growth: Join us as we scale from startup to category leader, with equity participation in our success
Product Influence: Directly shape pr