Senior Back-end Developer Python - CDI - Barcelona

Overview

As a Senior Backend Engineer, you will strengthen and scale the technical foundations for papernest's Spanish market operations. You’ll design and evolve backend services to support growth, reliability, and long-term scalability, acting as a bridge between operations and technology. You’ll shape architecture, establish best practices, and deliver resilient, high-performing systems aligned with strategic goals.

This role offers impactful work at scale in a fast-evolving, international environment.

• remote work (2 days per week)
• health insurance through Alan
• meal vouchers via Swile
• continuous training opportunities
• career development support
• BSPCE subscription bonuses

• Design and implement scalable backend services and APIs
• Improve system reliability, performance, and maintainability
• Partner with operations and business stakeholders to understand evolving needs
• Reduce technical debt through pragmatic decision-making
• Contribute to architectural standards and long-term platform strategy
• Support the scalability of the Spanish market with robust infrastructure

• 5+ years of backend development experience with architecture ownership
• Python (Django/FastAPI) expertise including event-driven or asynchronous architectures
• Experience managing complex API integrations and debugging data inconsistencies
• Ability to reverse engineer semi-technical workflows to understand business logic
• Professional English; Spanish is a plus

• Strong analytical and problem-solving mindset
• Pragmatic and structured approach in fast-moving environments
• Fast learner of business domains and bridging technical and operational topics
• Python (Django/FastAPI) with event-driven/asynchronous architectures
• API integrations and data debugging across external services
• Reverse engineering workflows to guide refactoring