Senior Software Engineer (AI) (m/w/d)

About Realist

Realist is an innovative WealthTech startup based in Germany, committed to transforming the financial industry through cutting-edge technology, data-driven insights, and scalable financial infrastructure. As we expand our platform and technology capabilities, we are looking for an experienced Senior Software Engineer to join our growing team in Berlin and help build the next generation of financial systems.

About the role 

As a Senior Software Engineer, you will play a key role in designing and building high-performance financial systems that process large volumes of data reliably and securely. You will work closely with product, engineering, and data teams to architect scalable systems and contribute to the development of intelligent, AI-driven financial applications.

This role requires strong experience in backend engineering, distributed systems, and data-intensive architectures, combined with a mindset suited for a fast-moving startup environment. We are particularly looking for someone who is a fast learner, able to quickly adapt to new technologies and evolving challenges.

Key Responsibilities

• Design, develop, and maintain scalable backend systems supporting data-intensive financial applications.
• Build and optimize high-performance OLTP systems for transaction-heavy workloads.
• Contribute to system architecture and design, ensuring reliability, scalability, and maintainability.
• Work with cloud infrastructure, particularly AWS, to deploy and manage production-grade services.
• Develop services using C#, Python, and Node.js within modern microservice architectures.
• Collaborate with data and engineering teams on data pipeline and OLAP system design where applicable.
• Implement and maintain AI-enabled features, including the development of agentic systems and AI-powered workflows.
• Apply modern AI engineering practices including LLM integration, evaluation frameworks (Evals), and guardrails.
• Contribute to engineering best practices, code quality standards, and technical mentorship within the team.
• Collaborate closely with cross-functional teams in a fast-paced startup environment.

Experience  

• Fluency in English, both written and spoken.
• Minimum 8 years of professional software engineering experience.
• At least 5 years of experience in the financial services or FinTech industry.
• Strong backend engineering experience with C#, Python, and Node.js.
• Proven experience building data-intensive OLTP systems.
• Experience with AWS cloud infrastructure and distributed systems.
• Solid system design and architecture skills.
• Experience working with large-scale data systems; exposure to OLAP system design is a plus.
• Strong team collaboration and communication skills.
• Ability to quickly learn and adopt new technologies and frameworks.
• Comfortable working in a startup environment with high ownership and autonomy.
• Strong exposure to modern AI engineering practices, including:
  • Building agentic systems
  • Experience with LangChain or similar frameworks
  • Working with Evals and Guardrails for LLM-based applications.

Compensation and Perks

•  An opportunity to help build the core technology of a rapidly growing WealthTech startup.
•  A collaborative and innovative engineering environment.
•  Competitive salary and compensation package.
•  The chance to work on cutting-edge AI and financial infrastructure systems.
•  Opportunities for professional growth and leadership as the company scales.

If you are a passionate and experienced software engineer looking to build advanced financial systems and AI-driven applications, we would love to hear from you.
 #LI-JM1
#LI-Hybrid