Full-Stack Software Engineer

Job Description

At Sumary , we are rebuilding finance from first principles. We are an AI-native fintech backed by the largest fintech pre-seed round ever raised in Denmark , on a mission to eliminate broken financial workflows and define the future of autonomous finance. This is a rare opportunity to join at the very beginning - to help build a new category of financial infrastructure, ship real product used by leading accounting firms, and shape how finance teams across Europe will work in the coming decade. As a Founding Full-Stack Software Engineer at Sumary, you will build, refine and ship AI-native financial workflow products used by bookkeepers, controllers and finance teams across Europe. Come help define and build the future of finance. What you will be doing Architect and implement features end-to-end Take real ownership of our codebase, balancing robustness, security and speed Work with technologies such as TypeScript/React/Next.js, Node.js, Postgres/Supabase, Temporal, Modal and AI service layers Design and evolve our internal platform, from data pipelines to workflow engines Drive continuous improvement and challenge us, the product and yourself Collaborate directly with founders, users and accounting firms to shape the real workflows we automate Who you are A passionate engineer with 3-5 years of experience building real products end-to-end Comfortable across the entire stack You are autonomous, resourceful and thrive with ownership A problem solver who can think holistically about system design Knowledgeable about AI and agentic workflows Experience with infrastructure, integrations, or financial/ledger data is a plus (but not required) Why this role Build foundational systems in a massive category ready for transformation Ship fast and see immediate real-world impact from bookkeepers and finance teams Join early, influence architecture, culture and engineering standards Work directly with second-time founders backed by byFounders, Partech, Tenity and top angels Help define what autonomous finance looks like in the coming decade