Senior Product Engineer

Your mission Join our Engineering team and own features from the problem to the shipped product, in a platform used by thousands of construction professionals. Own problems end to end: Take a customer or business problem all the way to production. You shape the solution and its acceptance criteria, design the data model and services behind it, and ship it across backend, API, and front end. Solve hard backend problems: Our domain is complex — tenders, bills of quantities, and millions of price data points. You design the data models, APIs, and services that handle it reliably and at scale. Make product decisions: Decide how a solution should work for the user, down to the interface, which you build on our design system with little guidance. Build our biggest bets: Partner with Product and Design on our most strategic initiatives, and own bringing them to life in the product. Collaborate across teams: Work with Product, Design, and Data to translate business problems into shipped features. Shape our codebase: Architect and implement modular packages and services in our monorepo. Your profile TypeScript, React, Node: Non-negotiable. You have significant professional experience building, shipping, and maintaining complex web applications. You’re comfortable shipping across the whole stack. End-to-end ownership: You’ve taken features from a loosely defined problem to real users, deciding scope and acceptance criteria yourself. Backend engineering depth: You design data models, APIs, and services, and you care about performance, reliability, and maintainability. UX taste: You care how your work feels to the user, and you make sound interface decisions without a detailed spec. Product mindset: You’re comfortable with ambiguity and focus on what makes the biggest difference for users. Sharp problem solver: You look at a complex system, quickly identify what matters, and decide what to do next. Bias for action: When you’re unsure something will work, your instinct is to find out with data rather than keep wondering. Excellent communication skills in English. Bonus points for Experience shipping AI-powered features (LLMs, agents) into a product. Experience with our infrastructure stack (AWS, Kubernetes, Terraform) and with CI/CD pipelines. How We Build: Our Engineering Culture We believe in a calm, collaborative, and productive engineering environment. We trust our engineers and give them the autonomy to do their best work. Our approach includes: Agile & Fast-Paced: We practice trunk-based development with daily releases to get value into our users’ hands quickly. Quality by Default: We maintain a comprehensive Cypress E2E test suite and enforce strict typing, linting, and formatting rules to keep our codebase clean and maintainable. DevOps Mindset: Our well-oiled CI/CD pipeline deploys to AWS via Kubernetes, with our entire infrastructure managed as code using Terraform. Collaboration & Transparency: We value open discussion, constructive code reviews, and a culture where the best idea wins, regardless of who it comes from. Why us? Competitive Compensation: A competitive salary above the market average. Work-Life Balance: Choose to work 100% remotely or from our modern office in Berlin. We offer flexible working hours to fit your life. Top-Notch Equipment: A new MacBook Pro to ensure you have the best tools for the job. A Great Team: Regular company off-sites and team events that connect us as people, not just colleagues. Job Security: A permanent contract in a stable, well-funded company. About us Cosuno – Revolutionizing construction through technology. We are Cosuno – a fast-growing tech startup that is making the construction industry more efficient and transparent with our digital platform for tenders and procurement processes. Our goal: to solve the most complex challenges in the industry with innovation and simplicity. Why Cosuno? Artificial intelligence is the key to our solution: it analyzes millions of price data points and helps construction companies create precise and efficient bids. This not only saves our customers time but also helps them avoid unnecessary costs. But for us, it’s not just about technology – it’s about the people who drive it. At Cosuno, you will work with creative minds who are reshaping the construction industry. We believe in diversity because we know that the best ideas come from different perspectives. An integrative and inclusive work environment is a matter of course for us. Join us – Build the future of construction.