Software Engineer - AI.

About the Role

This is a full-stack AI engineering role on a small, technical product and engineering team building AI-powered tools for construction professionals. You will own features end-to-end, from database schema and LLM integration through to UI, while also contributing to the internal platform foundations that let new use cases ship quickly.

What You'll Do

• Build and own end-to-end AI features from concept through production, including document versioning and agentic chat workflows.

• Design and implement features across the full development lifecycle: database schema, LLM tuning, evaluation, and UI.

• Manage evaluations, scoring, and error analysis on new and shipped AI features to ensure quality.

• Contribute to the workflow harness, decision-trace standard, and evaluation tooling that accelerates shipping new use cases.

• Build reusable human review and approval surfaces that earn trust in AI output.

• Model and evolve a construction domain ontology and project graph, including entity resolution across documents such as bills of quantities, contracts, and drawings.

• Design features that link answers to evidence and make decisions auditable and traceable.

• Extend multi-modal ingestion of unstructured documents (PDFs, scans, drawings, and 3D models) at scale.

• Build read/write integrations with customer systems (document management, ERP) to complete workflows end-to-end.

• Contribute to scalable data pipelines and support native BIM/DWG file processing.

What We're Looking For

• 3+ years of experience as a full-stack software engineer, ideally in fast-paced, early-stage B2B startup environments.

• Proven track record delivering production-grade applied AI features to customers.

• Proficiency with TypeScript, Python, and SQL for building full-stack applications.

• Experience building backend APIs and database schemas using frameworks such as Fastify and Prisma, or equivalents.

• Experience integrating and optimizing LLM APIs (OpenAI, Azure, Gemini, Cohere, or similar).

• Experience with cloud infrastructure such as AWS (RDS, S3, Elastic Beanstalk) or equivalent.

• Experience building data pipelines and ETL workflows for processing unstructured data at scale.

• Experience with vector databases and semantic search implementations.

• Experience designing and implementing evaluation frameworks and error analysis for AI systems.

• Experience building internal platform or developer-facing tooling that other engineers ship on top of.

• Full ownership mindset: comfortable designing and implementing solutions to customer problems end-to-end.

• Experience with workflow orchestration tools (Prefect, Airflow, or similar) is a plus.

• Experience with document processing, OCR, or multi-modal data ingestion is a plus.

• Experience with observability and monitoring tools (such as Datadog or Langfuse) is a plus.

• German language skills are helpful but not required; the team works in English.

Compensation & Benefits

Salary range: 80,000 to 120,000 EUR annually. Visa sponsorship is not available for this role.

Location

On-site, five days per week in Berlin, Germany. Candidates must be based in Berlin or willing to relocate.