Senior .NET Backend Engineer – Ownership ; Remote

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.

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.

• 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.

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

Practical requirements:

• Spanish residency and valid working permit
• Ability to meet face-to-face in Barcelona every ~2 months

• Azure experience in real production environments
• Familiarity with REST APIs and async patterns
• Comfortable reading, understanding, and improving existing codebases

• Shopify / Big Commerce

…is a bonus
, not a substitute for strong backend fundamentals.

• 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.

• 100% remote (Catalonia-based)
• 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