Senior Full-Stack Engineer (Backend-Leaning)

Job Description

Employment Type: Full-time
Work Model: Remote
Location: Bucharest, Romania

Role Overview

This is a senior, backend-leaning full-stack role for engineers who can own complex systems end-to-end, from Next.js frontends to NestJS backend APIs and cloud-native delivery.

The role combines hands-on development with architectural ownership, performance optimization, and cross-stack technical leadership, without becoming a delivery bottleneck.

Responsibilities

• Own and evolve large Next.js applications, using Pages Router today and planning migrations toward App Router patterns
• Manage complex frontend state using Redux and redux-saga
• Optimize frontend performance for feeds and real-time user interfaces
• Design and build robust backend services using NestJS, with strong validation, error handling, and API discipline
• Design and maintain secure authentication and RBAC authorization systems
• Ensure data correctness, performance, and scalability in MongoDB, including schema design and aggregation usage
• Use Redis for caching, coordination, and distributed state
• Understand and apply CDN and media delivery concepts, including signed URLs and caching behavior
• Collaborate across frontend, backend, and DevOps to set engineering standards and improve system reliability
• Mentor engineers across the stack while maintaining delivery velocity

Required Skills and Experience

Frontend Engineering

• Strong production experience with Next.js and TypeScript
• Experience working with Redux and redux-saga in complex applications
• Understanding of performance optimization for real-time or feed-based UIs

Backend Engineering

• Deep hands-on experience with NestJS in production environments
• Strong understanding of backend validation, error handling, and API design
• Experience building secure authentication and authorization systems

Data and Distributed Systems

• Strong MongoDB experience, including schema design and aggregation pipelines
• Practical experience using Redis for caching and distributed coordination

Cloud and Platform

• Comfort operating in GitOps-based workflows
• Experience working in Kubernetes environments
• Understanding of cloud-native delivery and operational best practices

Leadership and Ownership

• Ability to lead technically across frontend and backend without becoming a bottleneck
• Strong ownership mindset and attention to system reliability and maintainability
• Experience mentoring engineers and setting engineering standards