Our client, a fast-growing international startup, is redefining how people unlock the value of what they already own, turning circularity into a smart, frictionless payment experience. With a live product, real traction, and a modern tech stack, they are expanding their engineering team with a senior backend profile who enjoys building scalable, resilient systems that have a direct impact on business.
If you’re motivated by real technical challenges, modern architecture, and building AI-driven features from the ground up (not just buzzwords), keep reading.
The Role
The selected candidate will join an agile team with real autonomy. Core responsibilities include:
- Designing and building scalable backend systems (Python + Django REST Framework).
- Working on complex integrations across payments, ecommerce, logistics, and automation.
- Participating in architectural decisions and technical roadmap definition.
- Driving engineering quality through testing and TDD practices.
- Mentoring teammates and contributing to product direction.
- Helping build the AI infrastructure from scratch.
What We’re Looking For
Technical Background
- 5+ years of backend development experience (senior or lead level).
- Strong experience with Python and Django REST Framework (or similar: Ruby on Rails, Phoenix, Laravel, etc.).
- Strong testing mindset (ideally TDD).
- Knowledge of PostgreSQL, AWS, and security best practices.
- Comfortable with occasional frontend work (while remaining backend-focused).
- Solid understanding of system design and scalability.
Product & Business
- Genuine curiosity about how users experience the product.
- Ability to translate design specs into actionable engineering tickets.
- Interest in understanding the why, not just the what.
AI
- Interest in AI for productivity (code generation, automation).
- Excitement about building AI features and infrastructure from scratch.
- Curiosity about emerging AI capabilities.
Communication
- Fluent in English (spoken and written). Spanish is a plus.
- Pragmatic problem-solver who balances speed and quality.
- Collaborative mindset with mentoring experience.
Bonus
- Experience in fintech, payments, or ecommerce.
Tech Stack
- Backend: Python, Django REST Framework
- Database: PostgreSQL
- Frontend: Angular / Vanilla JS
- Integrations: PHP (ecommerce plugins)
What the Company Offers
- Competitive compensation.
- Fully remote role (optional hub in Barcelona).
- Flexibility: 5-hour overlap with Spanish business hours (9–19 CET).
- High autonomy in both technical and product decisions.
- Opportunity to build AI infrastructure from zero.
- Growing team with strong technical leadership.