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# Full-Stack Software Engineer

- **Company:** Número De
- **Location:** Barcelona, Spain (Remote available)
- **Salary:** €75,000.0 - €85,000.0
- **Contract:** Permanent contract
- **Skills:** JavaScript (Programming Language), Automation of Tests, Unit Testing, Microsoft Azure, Software as a Service, Microsoft SQL Server, Software Maintenance, Systems Integration, Test-Driven Development (TDD), Sql Optimization, Technical Debt, Front End Software Development, Service Stack, Web Api
- **Published:** September 19, 2026
- **Apply:** https://www.adzuna.es/contact-us.html

## About the Role

+ 7+ years of full-stack software development experience, with strong expertise in C# and .NET/Core, ideally within SaaS products.
 + Strong experience with modern frontend JavaScript frameworks.
 + Strong hands-on experience developing and integrating Web APIs.
 + Advanced SQL skills, with SQL Server experience preferred.
 + Strong knowledge of Test-Driven Development and automated testing, including both unit and integration testing.
 + Hands-on experience with Azure Cloud.
 + Azure DevOps experience is a plus.
 + Strong ability to build intuitive, reliable, and maintainable software.
 + Ownership mindset with a track record of following through on commitments and taking responsibility for technical outcomes.
 + Comfortable working independently in a small-team environment while actively collaborating with others.
 + Curious and proactive approach to learning, experimentation, and adopting new technologies.
 + Willingness to ask questions, challenge assumptions, learn from mistakes, and continuously improve.
 + Strong attention to detail and a commitment to engineering excellence.
 + Self-driven approach with the ability to use sound judgment and seek alignment when needed.
 + Currently based and legally authorized to work within a European country in the CET, EET, or WET time zones.

## Description

This position is listed on behalf of a partner company, who manages all applications and next steps. Our partner is looking for a Senior Full-Stack Software Engineer based in Spain.
This is a fully remote opportunity for a senior engineer who can take ownership of complex software projects from concept through launch. You will contribute across the full technology stack, building new product capabilities while maintaining a strong focus on quality and automated testing. The role combines hands-on development with technical ownership, architectural thinking, and continuous exploration of new technologies. You will work closely with a distributed engineering team to shape technical solutions, coding standards, and development practices. The environment values autonomy, curiosity, attention to detail, and a strong sense of ownership. You will have the opportunity to make a meaningful impact on a growing SaaS product while working with a modern cloud-based technology stack.
Accountabilities:

 + Deliver senior-level implementation of new product features across the full technology stack.
 + Own projects from technical conceptualization through implementation, testing, launch, and continuous improvement.
 + Design and implement reliable, maintainable, and scalable software solutions.
 + Build comprehensive test automation for new development, including unit and integration testing.
 + Solve complex technical challenges while balancing product requirements, engineering quality, and maintainability.
 + Research, evaluate, propose, test, and implement new technologies, techniques, and development approaches.
 + Collaborate with engineers and other stakeholders on technical design, coding standards, development practices, and best practices.
 + Contribute to maintaining a high-quality engineering environment with minimal technical debt.
 + Continuously improve development processes, tooling, and engineering practices.
 + Take ownership of technical decisions and proactively identify opportunities to improve the product and engineering experience.