Full Stack Data Engineer (m/f/d)

Berlin Mitte Hybrid (2 days/week remote) €60,000-75,000 + VSOP equityHelp us decarbonize cement and concrete - not tomorrow, today.alcemy is on a mission to keep 100 million tons of CO₂ out of the atmosphere every year by 2030. Making concrete accounts for around 8% of global CO₂ emissions, and our machine-learning software runs inside cement and concrete plants 24/7 to cut it - without sacrificing quality or driving up costs. We're already live in a third of Germany's cement plants and 30+ ready-mix concrete plants.The roleAs our Full Stack Data Engineer, you'll own the data that powers everything we do - the flow of cement and concrete plant data from raw, messy ingestion through cleaning, to the pipelines our machine-learning recommendations run on. The split is roughly 50% data engineering, 50% backend, and it's refreshingly hands-on with customers: you'll dig into real-world data, explain what you find to non-technical people, and make getting data into alcemy dramatically easier.What You'll DoBuild and own the pipelines that ingest and clean messy plant data into something our ML can useHelp us move from strict, structured data requirements toward flexible, AI-powered ingestion - so customers onboard with far less frictionTrack down data anomalies and explain your findings to customers in plain languageBuild and maintain the APIs and PostgreSQL databases behind our products, and keep production running smoothlyWork shoulder to shoulder with customers, sales, and customer success - translating between the technical and the non-technicalRequirementsYou'll thrive here if... Above all, you care about climate change and want your work to count.Must-havesYou've deployed production-grade Python applicationsYou love getting to grips with an unfamiliar codebase quickly, and you're eager to start delivering work that matters from the startYou're comfortable working directly with customers, sales, and customer success - patient, plain-spoken, and at ease with non-technical enterprise teamsYou're open to using AI tools to augment how you workNice-to-havesExperience with Flask or Django and Fast APIPostgreSQL or similar SQL databasesSome exposure to machine learningDon't tick every box? We'd still love to hear from you.How We WorkNo lone warriors - you'll work collaboratively alongside senior and junior engineers, owning features end to end: build, test, review, deploySmall team, direct customer exposure, fast startup pace - so async communication, sharp prioritisation, transparency, and direct feedback are the norm, and how we work is something we shape together, and keep improvingWe use Claude Code responsibly - AI to move fast, engineers always in charge and accountable, no AI-slop merge requestsHybrid by design (Berlin Mitte office, up to 2 days remote, plus offsites and boat trips), with real room to grow along technical-expert or management tracks - and the chance to lead a product area within a couple of yearsBenefits25 days' vacation - plus an extra day for every 2 years here, and the days between Christmas and New Year off€1,500/year and 3 days/quarter for your own developmentThe Mac of your choiceAn office in the heart of Berlin MitteOur Tech StackBackend & data: Python throughout - FastAPI (auto-generated Swagger/OpenAPI), SQLAlchemy, pydantic, pytest, mypy; pandas, polars, numpy, sklearn; uv for dependenciesInfra: PostgreSQL, AWS on Kubernetes managed with Terraform, ArgoWorkflows for scheduled jobs, GitLab for codeFrontend: React & Next.js in TypeScript with TailwindCSS; Blueprint.js / Radix UI; TanStack Query or axios; Streamlit for internal toolsOur Hiring Process is fully remoteIntro call with our RecruiterMeet our Hiring ManagerA take-home task that mirrors the real work you'd be doingTechnical interview (90 min) with two engineers, including 30 min of live codingTeam-fit interview (45 min) with two future teammates At alcemy, we're building a team as diverse as the industry we're transforming. We welcome applications from everyone and assess every candidate on merit alone - regardless of gender, age, ethnic or national origin, religion or worldview, disability, sexual orientation, or gender identity. We especially encourage people who are underrepresented in tech to apply. If you need any adjustments to take part fully in our hiring process, just let us know and we'll make them.Note: We don't currently offer visa sponsorship, so you'll need a valid EU work visa.