We are hiring a true senior backend engineer to help us scale and evolve a long-running, production SaaS platform used daily by ecommerce merchants at real volume.
This role is not suitable for developers who require close supervision or step-by-step guidance. We are looking for someone who can take full ownership of backend features end-to-end and deliver reliable, well-tested, production-ready solutions .
If you enjoy responsibility, autonomy, and building systems that matter in the real world, this role will suit you very well.
The Product
We build an AI-enhanced ecommerce content platform that helps merchants improve conversion rates, customer trust, and organic visibility across traditional search engines (Google) and emerging AI-driven search channels (ChatGPT, Perplexity, etc.).
Our platform:
Serves millions of page views
Manages thousands to tens of thousands of products per client
Uses LLMs to generate, maintain, and validate structured Q&A and content at scale
Has been in continuous production for 15 years
Is profitable, stable, and growing
This is not a greenfield experiment or a short-lived startup — it is a mature product with real customers, real data, and real technical challenges.
What You Will Own
Design and implement backend features in C# / .NET
Build and maintain Azure-based services (App Services, Functions, Storage, SQL)
Work hands-on with SQL Server : schema design, indexing, query optimization
Integrate AI / LLM services where they add clear, measurable value
Deliver code that is tested, readable, maintainable, and production-ready
Understand requirements, ask the right clarifying questions, and execute without micromanagement
You will have meaningful influence on how the system evolves technically over time.
This Role Requires (Non-Negotiable)
You must have done the following professionally:
Built and maintained production .NET backend systems for several years
Worked on a SaaS or high-traffic system, not only internal tools
Be very solid in programming fundamentals (data structures, async flows, error handling, separation of concerns)
Debugged real production issues and taken responsibility for fixing them
Worked independently with minimal supervision
Have 6+ years of full-time professional programming experience
Be fluent in English
Practical requirements:
Spanish residency and valid working permit
Ability to meet face-to-face in Barcelona every ~2 months
Technical Expectations
Strong C# / .NET backend experience
Solid SQL Server knowledge (queries, indexes, schema design)
Azure experience in real production environments
Familiarity with REST APIs and async patterns
Comfortable reading, understanding, and improving existing codebases
Some frontend experience (MVC, JavaScript, basic UI logic)
Experience with:
LLM APIs (OpenAI, Azure AI)
Shopify / BigCommerce
...is a bonus, not a substitute for strong backend fundamentals.
How We Work
Small team, high trust
Clear, written requirements and expectations
Very little hand-holding
Strong focus on quality, correctness, and follow-through
Preference for calm, thoughtful engineering over rushed output
We value people who care about doing things properly and take pride in their work.
Practical Details
100% remote (Catalonia-based)
Flexible working hours
Competitive salary: €40,000 – €65,000, depending on demonstrated seniority and ownership level
Long-term role with room to grow into technical and architectural leadership