Senior Full Stack Engineer

About Us

Join us on our mission to build the leading crypto trading super-app. By tightly linking alpha discovery with trading, we seek to empower crypto traders to better filter through the noise and act on validated alpha through social network embedded and mobile-first experiences. Think of Zap as the web3 trader-native social layer, backed by top tier investors such as Bain Crypto, Delphi Digital, and Jump Crypto.

Role

As a Senior Full Stack Engineer at Zap, you will work across the entire stack to build and deliver powerful, real-time tools for traders. You will collaborate closely with both frontend and backend engineers to architect and implement systems that process high-frequency data, power advanced analytics, and deliver responsive, real-time user experiences. This role is ideal for engineers who are equally comfortable building performant user interfaces and robust backend services — and who thrive in performance-sensitive, data-intensive environments.

Please note, this role is hybrid, candidates must be able to work from our office in Athens, Greece.

Key Responsibilities

• Design and build end-to-end features across both frontend and backend
• Implement real-time APIs and data pipelines using WebSockets and REST
• Build and integrate frontend components using React, Next.js, and TailwindCSS
• Architect efficient backend services for streaming and querying multi-dimensional data
• Optimize performance across the stack — from server response times to client-side rendering

Requirements

Must have

• 4+ years of experience in full stack, frontend, or backend engineering
• Strong proficiency in TypeScript across both backend and frontend
• Deep experience with Next.js and React
• Solid backend development experience with Node.js, Express, or similar frameworks
• Proven experience building and integrating WebSocket-based real-time APIs
• Experience designing and consuming RESTful APIs (GraphQL a plus)
• Familiarity with PostgreSQL
• Fluent in written and spoken English

Nice-to-haves

• Experience with financial or time-series data systems
• Familiarity with Lightweight Charts (TradingView) or other data visualization libraries
• Experience working with message queues and event-driven architectures
• Exposure to SSR/SSG/ISR patterns in Next.js
• Familiarity with performance profiling tools across both frontend and backend
• Experience with E2E testing (Playwright, Cypress) and integration testing at the API layer
• Background in fintech, trading platforms, or analytics-heavy products

Why Work with Us

• Competitive salary and equity/token compensation
• Opportunity to work with cutting-edge technology and a brilliant team
• Health insurance coverage & wellness benefits
• Collaborative and inclusive work culture
• Exciting company events and team-building off-sites