Senior Software Developer

Are you an experienced fullstack developer with strong backend expertise and a passion for building scalable software using modern technologies? Join one of Europe's most established HR tech companies, Sympa, and help us accelerate our growth across the Nordics.

Type: Full-time, permanent

Location: Espoo or Lahti, Finland (hybrid)

Starting date: As soon as possible, negotiable

Over the last 20 years, Sympa has helped some of the largest companies in the Nordics put people at the centre of their strategy. With over 1,000 customers and a strong install base, we're on a mission to continue growing. Our Engineering hubs are in Espoo (Finland), Lahti (Finland), and Poland, and you would join a highly talented, international team of over 55 engineering colleagues.

Our solution is built on Microsoft Azure. The technologies we use include .NET and modern frontend frameworks (React, ), Domain-Driven design, API-first architecture, Azure Compute and Data Services, and various SQL and NoSQL databases. We are also rapidly scaling our use of AI across our entire product and engineering organization.

As a Senior Developer, you will play a key role in designing, implementing, and maintaining both backend and frontend components of our software systems—with a particular emphasis on backend architecture, data structures, and API design. You will contribute to architectural decisions, mentor junior developers, and collaborate across teams to deliver high-quality, scalable features. A strong foundation in Azure is critical for this role, as our entire platform relies on Azure-native services.

What you get to do as a Senior Software Developer

• Design, implement, and maintain backend (.NET/C#) and frontend (React, ) components across our platform, with a strong focus on backend robustness and scalability.
• Ensure that system architecture follows best practices in scalability, security, performance, and maintainability.
• Perform rigorous code and design reviews across the full technology stack.
• Research, troubleshoot, and resolve complex technical issues—especially those related to backend services, data flows, and integrations.
• Conduct comprehensive unit, integration, and end-to-end testing to ensure software robustness and reliability.
• Participate actively in Scrum ceremonies, including sprint planning, daily stand-ups, reviews, and retrospectives.
• Support and optimize fullstack CI/CD pipelines to ensure efficient builds, testing, and deployments.
• Mentor junior developers, sharing knowledge on backend architecture, frontend best practices, and overall engineering principles.
• Collaborate with UX/UI designers to deliver intuitive, high-quality user interfaces.
• Handle and coordinate support cases as needed, ensuring timely resolution.
• Advocate for continuous improvement across engineering processes, tools, and practices.
• Take on additional responsibilities as needed to help the team and company succeed.

What do we value in our candidates?

We're looking for someone with a strong fullstack background, particularly in backend development. You are motivated, curious, and ready to take ownership. You enjoy solving complex problems, collaborating across teams, and supporting others in continuous learning and improvement.

Furthermore, the following skills and experience are needed to succeed

• A solid software development experience (+8 years), with strong fullstack expertise and a clear emphasis on backend development.
• Proficiency in C#/.NET for backend development and experience with modern frontend frameworks (React, ).
• Strong understanding of RESTful APIs, backend integration patterns, and microservices architecture.
• Experience working with SQL and NoSQL databases, including designing efficient data structures and queries.
• Hands-on experience with Azure cloud services is mandatory, including the ability to design, deploy, and maintain applications using Azure-native components.
• Experience developing maintainable and scalable backend systems, with an understanding of performance optimization.
• Solid experience with agile methodologies, especially Scrum.
• Experience and openness toward using AI technologies in software development, whether for improving engineering workflows or enabling new product capabilities.
• Excellent problem-solving skills and the ability to work across multiple product areas.
• Demonstrated ability to mentor and support developers, fostering a collaborative team culture.
• Degree in Computer Science, Engineering, or a related field.

Why Sympa?

Sympa is striving for fast international growth while maintaining the agility of a small business, and this shapes our work culture. Decisions are made quickly, with a flat hierarchy. We're driven by clear goals, ownership, and a fast-paced, commercially focused mindset. If you're looking for a friendly yet ambitious environment where collaboration meets accountability, you'll feel right at home.

Innovation: Work with the latest technologies and tools.

Collaboration: Join a diverse team of talented Sympaticans in an agile and flexible environment.

Impact: Build solutions that make a real difference for our customers.

Benefits: Enjoy perks such as lunch and cultural benefits.

Growth: Become part of a company that invests in your development.

Got your attention?

Great—let us know who you are by sending us your CV and a short application letter. The position will be filled as soon as we find the right candidate.

If you have any questions about the role, feel free to reach out to the hiring manager of the role:

Pasi Jakonen

Head of Software Development

Sympa believes that an equal, diverse, and inclusive work environment fuels creativity, innovation, and openness—everything we value on our global growth journey.

We provide equal opportunities to all qualified applicants regardless of gender, gender identity, age, nationality, religion, disability, sexual orientation, or any other personal characteristics.

We want everyone to be themselves and to thrive in our inclusive work environment.

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