Staff Software Engineer

The Role As a Staff Software Engineer in our Supply domain, you won't just be writing features; you will be setting the technical direction that shapes the future of our platform. In 2026, our primary mission is foundational modernization. We are leading the charge in modernizing our architecture; shifting from legacy systems and transitioning our ecosystem from Go toward a unified Java/Kotlin/Spring stack. You will define the patterns and standards that guide this transition across the domain, spending roughly 20% of your time raising the bar for other engineers and 80% attacking our hardest technical problems, all with a high degree of autonomy and ownership. The Team The Supply domain is composed of talented engineers distributed in multiple countries across Europe and the US. We build the critical infrastructure that manages and standardizes the flow of survey data to our global network of suppliers. We believe in strong collaboration and team work, high quality engineering, and providing the best possible experience for our customers. What You’ll Do Collaborate on this modernization journey : Design and implement patterns for legacy displacement to move domains out of our monolith with zero downtime. Set Technical Direction : Own the architectural vision for legacy displacement across the domain, defining the patterns, standards, and trade-offs that the wider team builds against, not just for your own work. Level Up the Team : Multiply your impact by mentoring senior and mid-level engineers, raising the quality bar through design reviews, and growing the team's collective technical depth. Bridge Tech Stacks : Build new services and help transition others from GO to Spring while navigating and contributing to other codebases. Product Collaboration : Partner with product managers to question and form requirements, understand the "Why", and help shape a roadmap that balances technical debt with new value. Global Collaboration : Communicate effectively across timezones. Your written documentation and async communication will be the glue for our distributed team. Master Observability : Use Grafana and modern tracing to monitor system health, ensuring our backend-heavy domain remains performant and reliable. Drive AI Efficiency : Leverage Agentic programming tools (like Claude Code) to accelerate refactoring and development workflows. Use it to deal with obvious problems and focus on the complex ones. Who You Are Deep Technical Expertise: You bring significant backend engineering experience (typically 10+ years) with the technical depth to be a go-to authority in performance-sensitive, production-critical systems. Fullstack-Minded Backend Expert: You have deep experience in backend systems and feel comfortable switching between languages. While backend is your priority, you don't shy away from the frontend; practical expertise in React sis highly welcomed. Collaborative Team Player : You have a strong collaboration mindset. You believe that success happens together and you actively seek to mentor others and share knowledge across the team Systems Thinker : You are comfortable with event-driven systems, and have a proven track record of breaking down monoliths and managing system migrations. Quality Obsessed : You believe that code without a robust test suite (Unit, Integration, E2E) isn't finished. Pragmatic & Curious : You have a strong product mindset. You don’t just take tickets; you seek to understand the business impact of your architectural choices. Observability Advocate : You don't wait for a crash to know there's a problem; you build systems that tell you how they're performing. Working at Keystone AI Remote-First: Work from anywhere where Keystone AI operates with a setup that supports your best work. High Autonomy: We trust our engineers to make sound decisions and own their work end to end. Global Impact: Your work powers a marketplace used by millions of people worldwide Our Values Collaboration is our superpower We uncover rich perspectives across the world Success happens together We deliver across borders. Innovation is in our blood We’re pioneers in our industry Our curiosity is insatiable We bring the best ideas to life. We do what we say We’re accountable for our work and actions Excellence comes as standard We’re open, honest and kind, always. We are caring We learn from each other’s experiences Stop and listen; every opinion matters We embrace diversity, equity and inclusion. More About Keystone AI We’re proud to be recognised in Newsweek’s 2025 Global Top 100 Most Loved Workplaces®, reflecting our commitment to a culture of trust, respect, and employee growth. In June 2021, Keystone AI acquired Berlin-based GapFish – the world’s largest ISO certified online panel community in the DACH region – and in January 2022, completed the acquisition of US-based Lucid – a programmatic research technology platform that provides access to first-party survey data in over 110 countries. Keystone AI Group AB (publ), listed on Nasdaq Sto