Senior Software Engineer
Company: Haystack
Location: Tallinn, Harjumaa (Remote)
Type: Full-time
Level: Senior
Remote: Yes
Posted: 2026-02-14
About this role
Senior Software Engineer .NET (AaaS)
We're working with Riverty on this exciting opportunity. Join a fast-growing fintech organization as a Senior Software Engineer, focusing on their innovative Accounting as a Service product. This role involves enhancing backend systems in the Azure Cloud to meet the demands of a growing business in the e-commerce and mobility sectors.
The Role
• Assist in architectural and coding challenges, supporting migration, refactoring, and modernization of Azure cloud environments.
• Design, build, test, and deploy robust, maintainable code and APIs with a focus on automation and reliability.
• Analyze requirements critically, challenge assumptions, and contribute to system architecture aligned with business needs.
• Drive best practices and standards, actively identifying and fixing inefficiencies.
• Shape engineering culture, providing feedback, adopting new ideas, and questioning the status quo.
• Mentor team members and set a high standard for quality and architectural thinking.
What You'll Need
• 6+ years of hands-on experience in C#/.NET, including significant contributions to architectural decisions.
• Strategic, outcome-driven experience with cloud platforms, preferably Azure.
• Proficiency in designing user-friendly RESTful APIs.
• Experience with microservices, distributed architectures, and event-driven integration.
• Practical, production-level exposure to messaging systems like RabbitMQ or Kafka.
• Basic experience with frontend JS frameworks for communication and prototyping.
• Ability and willingness to challenge assumptions, prioritize ruthlessly, and defend technical choices.
• Strong written and spoken English.
• EU citizenship or a valid work permit for Estonia is required.
What's On Offer
• Be part of a dedicated development team in a rapidly expanding fintech company.
• Contribute to a product that simplifies accounting for international businesses in e-commerce and mobility.
• Hybrid working cond...