Senior ML Engineer

Department: Tech

Location: Berlin/Remote

Employment Type: FullTime

Your mission

Join our AI team and build the intelligent systems at the core of Cosunos platform.

• AI for Construction: Take new models and AI capabilities from idea to production — design, train, evaluate, deploy, iterate — and own them end to end.

• Price Prediction: Improve the models that help users evaluate bids and make better procurement decisions, trained on millions of price data points.

• Ranking, Search & Retrieval: Iterate on the systems that match the right subcontractors to the right tenders.

• Experimentation & Evaluation: Design offline evals, run online A/B tests, and drive metrics-led iteration.

• AI Agent Development: Build and improve our agentic system that orchestrates multi-step reasoning to navigate the complex, often messy tendering workflow.

• Ship into the product: Take your work all the way to real users — model, backend service, API, and the integration into our TypeScript web app.

• Collaborate across teams: Work with Product, Engineering, and Data to translate business problems into shipped ML/AI features.

• Maintain production ML & AI: Monitoring, alerting, and continuous improvement of everything we deploy.

Your profile

• Strong ML & deep learning background: You have 5+ years building, training, and shipping machine learning models — classical ML and deep learning — in production. Youre fluent in a modern deep learning framework, ideally PyTorch.

• Strong Python: You have 5+ years writing production-grade Python. You write clean, well-structured code.

• LLM application depth: You have deep hands-on experience building and deploying LLM/agent systems — RAG, tool use, multi-step reasoning, evals.

• Experimentation rigor: You know how to evaluate models properly — offline metrics, online A/B tests — and let the data decide.

• TypeScript, React, Node: Youre comfortable shipping your work into our web app — backend service, API, and front-end integration.

• End-to-end product delivery: Youve shipped features (not just models) into a production system and owned the path from research code to real users.

• Product mindset: Youre comfortable with ambiguity and can judge when something is good enough to ship.

• Sharp problem solver: You look at a complex system, quickly identify what matters, and decide what to do next.

• Bias for action: When youre unsure something will work, your instinct is to find out with data rather than keep wondering.

Bonus

• Experience building search/ranking/recommendation systems or pricing models

• Experience with embedding models, fine-tuning, or model training at scale

• Domain exposure to construction, procurement, or marketplaces

Why us

• Shape a product that solves real-life problems in the construction industry

• Work in an open-minded, collaborative, dynamic, and international team

• Fully remote team and work culture

• Freedom in your working hours. Its the results that count.

• Company off-sites and regular team events (offline and online)

• Flexible working conditions with the possibility to do workations

• Competitive compensation, a permanent contract, and modern work equipment

• Open feedback culture with regular 1-on-1s

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.