Senior Fullstack Software Engineer

Overview

unybrands Cologne, North Rhine-Westphalia, Germany

unybrands was established in 2020 by a group of partners united by a shared vision: to build the leading next-generation e-commerce platform for micro-brands. Headquartered in Miami, the company has a global presence with teams in Berlin, London, New York, and China. unybrands acquires e-commerce businesses that sell both on and off Amazon. Once acquired, these brands are integrated into unybrands\‘ platform, where operations are optimized, business performance is enhanced, and expansion into new product lines and markets is driven. Currently we have acquired 30 brands across Pet Care, Personal Care, Home Care, Supplements, Baby & Juvenile, Garden & Outdoor, Sports & Fitness, and Home, Lifestyle Culinary & Arts. Through expert management and robust infrastructure, unybrands empowers e-commerce brands to scale and thrive.

About The Role

Build a greenfield Rust-based operational platform from the ground up. You\’ll design and deliver end-to-end features powering multi-million-dollar e-commerce operations across Amazon, Shopify, and TikTok.

Work across the stack — from React UIs to async Rust services — solving challenging distributed systems problems like rate limiting, durable async workflows, and multi-channel data synchronization.

Why You’ll Love This Role

• Greenfield Rust platform: Help shape architecture and patterns from day one
• End-to-end ownership: From UI to async backend to production deployment
• Challenging problems: Multi-channel synchronization, rate limiting, and distributed reliability
• High impact: Your work directly supports millions in e-commerce revenue
• Autonomous environment: Small team with minimal bureaucracy

What You’ll Do

• Design and implement features end-to-end: React UI, backend APIs, async processing, and data persistence
• Build and maintain integrations with Amazon SP-API, Shopify, TikTok, and other marketplaces
• Architect resilient systems that handle eventual consistency, partial failures, and retry logic
• Develop queue-based async flows with robust error handling and correlation tracking
• Implement operational features: multi-channel pricing, inventory sync, and order processing
• Create real-time dashboards and monitoring tools for visibility and observability
• Participate in code reviews, mentor team members, and improve system reliability over time

Technical Stack

Backend:

• Rust with Axum (async framework on Tokio)
• PostgreSQL (GCP Cloud SQL with HA)
• SQLx for type-safe queries and migrations
• Redis

Frontend:

• React with TypeScript
• Vite, Tailwind CSS, Shadcn

Architecture:

• Modular monolith with async-first design
• Event-driven processing (SQS)
• Durable state workflows

Infrastructure:

• GCP (Cloud SQL, GKE, Cloud Storage)
• AWS (SQS for notifications)
• Prometheus + Grafana for monitoring

Requirements

• 7+ years building production web applications
• Strong experience in statically-typed languages (Rust, TypeScript, Go, C#, or Java)
• Solid background with React or similar modern frontend frameworks
• Deep understanding of async programming, concurrency, and distributed system concepts
• Strong SQL and schema design skills
• Experience building and maintaining RESTful APIs
• Excellent debugging, communication, and problem-solving skills

Nice to Have

• Experience with e-commerce APIs (Amazon SP-API, Shopify, etc.)
• Background in high-reliability or operational systems
• Familiarity with event-driven design, idempotency, and backpressure handling
• Experience with GCP, Kubernetes, or container orchestration
• Knowledge of durable state management and crash recovery techniques

unybrands is an equal opportunity employer and considers all applicants for employment without any regard to race, skin color, religion, gender identity, sexual orientation, and age. Nor are applicants discriminated against based on disability or protected classes.

Seniority level

• Mid-Senior level

Employment type

• Full-time

Job function

• Industries: Construction, Software Development, and IT Services and IT Consulting