Senior Frontend Developer (React/JavaScript)

Senior Frontend Developer (React / JavaScript)

Location: Hamburg, Germany (Hybrid / On-site)

Experience: 5+ years

Type: Full-time

Level: Senior

About the Company

We are a fast-growing startup building AI-driven solutions for global freight and shipment companies.

Our platform works with some of the largest companies in the world, handling complex logistics workflows and real-time data at scale.

We work in a cloud-native, microservices-based architecture on AWS and Kubernetes, and every developer has a huge impact on day-to-day product decisions and implementation.

This is not a “small tasks only” role — you will own features end-to-end, influence architecture, and directly shape the product.

Role Overview

We are looking for a Senior Frontend Developer with strong, hands-on experience in pure JavaScript and modern React development.

You will take responsibility for designing, building, and delivering production-ready web applications, working closely with backend developers, product, and stakeholders.

A key part of the role is working with our internal frontend libraries and shared npm packages, contributing to their design, maintenance, and evolution across multiple applications.

We value developers who take ownership, care about quality, and get things done.

Responsibilities

• Design, develop, and maintain complex frontend applications using React and TypeScript
• Take features end-to-end: from requirements, through implementation, testing, and delivery
• Develop, maintain, and evolve internal npm packages and shared frontend libraries used across multiple products
• Ensure consistency, reusability, and high quality across shared components and packages
• Work closely with backend developers on REST and real-time (Socket-based) integrations
• Collaborate with product managers, designers, and other engineers to deliver high-quality solutions
• Write clean, maintainable, and scalable code
• Ensure high performance, reliability, and excellent user experience
• Actively participate in architectural discussions and technical decisions
• Debug, test, and optimize existing functionality
• Mentor other developers and contribute to a strong engineering culture

Required Skills & Experience

• 5+ years of professional frontend development experience
• Strong knowledge of pure JavaScript (ES6+) and browser fundamentals
• Deep experience with React, including Hooks and modern patterns
• Experience with TypeScript
• Experience building applications with Vite or similar modern build tools
• Experience building, maintaining, and consuming npm packages (internal or public)
• Understanding of versioning, dependency management, and backward compatibility
• Hands-on experience consuming REST APIs and working with real-time data (WebSockets / Sockets)
• Solid understanding of frontend architecture, state management, and component design
• Experience writing and maintaining tests (unit, integration, or e2e)
• Ability to work independently and also as part of a team
• Strong communication skills and ownership mindset

Nice to Have

• Full-stack experience with Node.js
• Experience working in AWS-based environments
• Familiarity with Kubernetes (K8s) and cloud-native architectures
• Experience working in startup or fast-paced environments
• Experience with AI-driven products or data-heavy applications
• Knowledge of performance optimization and frontend security best practices

What We Offer

• A senior role with real influence on product and technical direction
• Opportunity to work with cutting-edge technologies across frontend, backend, and cloud
• Work on a real-world AI solution used by major global freight companies
• Startup environment with high ownership and responsibility
• Collaborative team culture with room to grow technically and professionally
• Competitive salary and benefits
• Location: Hamburg, Germany