Senior Backend Engineer

About the role

You will build the core engine that powers our rankings and benchmarks for hospitals worldwide: a versioned, fully reproducible computation layer that transforms harmonized metrics into comparable scores. The focus of this role is algorithmic computation, mathematical correctness, and system reproducibility - web application development is a limited aspect of this system. As the senior technical owner for this area, you will design how scoring definitions, formula trees, category mappings, and peer-group logic are modeled as data and executed deterministically over time. You own the deep technical decisions that ensure calculation integrity across changing requirements and evolving data landscapes. You will partner closely with methodology experts to translate complex healthcare rating systems into robust, maintainable software abstractions. This position is centered on foundational computation rather than frontend user interfaces, emphasizing correctness, auditability, and long-term maintainability. Your work will directly influence how organizations around the world compare and evaluate hospital performance based on harmonized data.

Key facts

What you'll do

• Architect and implement a typed, versioned computation graph (DAG) that executes deterministically with clearly defined boundary contracts for hospital scoring.
• Model intricate business logic - including formula trees, categorical mappings, peer selection, and comparability adjustments - as versioned, declarative data structures that can be safely evolved.
• Establish end-to-end system lineage, versioning, and execution auditability, guaranteeing that any score can be recalculated identically at any future date using historical definitions.
• Design and deliver clean, typed internal services and API contracts that support both methodology workbenches and downstream consumer applications with strict reliability expectations.
• Define and enforce rigorous testing practices, such as golden file testing, property-based testing, and regression validation suites, to prevent calculation drift and silent errors.
• Shape architectural direction and drive critical trade-offs between execution speed, resource efficiency, and operational cost within cloud-based environments.
• Set and mentor code review standards, contributing to a sustainable engineering culture that supports both current and future hiring within the methodology computation team.
• Collaborate with data scientists, analysts, and product stakeholders to ensure that evolving healthcare metrics and benchmarking rules are reflected accurately and safely in the computation layer.
• Implement monitoring and observability for calculation pipelines to detect anomalies, performance regressions, and inconsistencies before they affect published results.
• Act as the technical domain expert for hospital scoring systems, documenting assumptions, edge cases, and decision rationales for long-term institutional knowledge.

Requirements

Core Requirements (Must-Haves)

• Graph Algorithms & Engine Concepts: Deep expertise in modeling and evaluating expression trees and dependency graphs, including ASTs, DAGs, cycle detection, topological sorting, memoization, and selective recomputation strategies.
• Advanced Python & Typing Discipline: Mastery of modern Python with strict typing discipline using tools such as mypy or pyright, along with explicit testing practices and clean packaging approaches.
• Deterministic System Design: Proven experience building auditable, reproducible systems that rely on immutable execution records, versioned schemas, and explicit data lineage tracking across complex calculation workflows.
• Declarative Logic & Domain Modeling: Experience treating business logic as versioned data, working with expression trees, rules engines, or domain-specific configurations that enable safe evolution of behavior.
• Typed API & Schema Design: Demonstrated ability to design, version, and operate production backend contracts and schemas for both upstream workflow engines and downstream consumer applications in high-stakes environments.
• Healthcare or Benchmarking Domain Familiarity: Basic understanding of healthcare key performance indicators, quality metrics, or benchmarking concepts, with familiarity with hospital rating systems, medical classification, or complex scoring methodologies being especially valuable.
• Methodical Testing Approach: Commitment to structured testing methodologies, including edge-case identification, boundary validation, and systematic regression detection for calculation integrity.
• Communication & Collaboration Skills: Ability to work effectively with non-technical stakeholders, translate ambiguous requirements into precise specifications, and document technical decisions for multidisciplinary audiences.

Nice to Haves (What Will Make You Stand Out)

• Web Frameworks & Orchestration: Production experience with FastAPI or similar async frameworks, combined with workflow tools such as Dagster, Prefect, or Airflow for managing complex calculation pipelines.
• Performance Profiling: Practical experience analyzing execution memory footprints, CPU profiles, and query efficiency, particularly when operating against columnar data warehouses or large-scale analytical stores.
• Cloud Infrastructure: Familiarity with deploying, monitoring, and operating containerized calculation microservices on AWS, including relevant scaling and resilience patterns.

Your Profile

• Degree: Bachelor's or Master's in Computer Science, Software Engineering, Applied Mathematics, or a related quantitative field that provides a strong foundation for complex algorithmic systems.
• Experience: 5+ years in backend software engineering, with a focus on building computation engines, rules platforms, or complex data-intensive backend systems, including a sustained period within one organization seeing a core system through build, launch, and iteration.
• Domain Knowledge: Healthcare or benchmarking domain experience is a plus, including basic familiarity with healthcare KPIs, quality metrics, or benchmarking concepts, and prior exposure to hospital rating systems, medical classification, or intricate scoring methodologies.
• Mindset: Strong analytical and mathematical mindset, with a proven capacity to translate complex domain logic and formulas into clean, deterministic software abstractions that remain reliable over time.
• Languages: Fluent in English, with German being a valuable additional skill for collaboration within European teams and stakeholders.
• Working Style: Highly structured, detail-oriented, and intrinsically motivated to collaborate closely with methodology experts, analysts, and cross-functional engineers to ensure accurate and trustworthy calculation outcomes.

Practical notes

This role operates at the intersection of data engineering, algorithmic computation, and backend system design. Successful candidates will demonstrate a strong commitment to correctness, reproducibility, and long-term maintainability in complex calculation environments. The position requires patience for deep technical problem-solving and the ability to work methodically with evolving requirements in a fast-growing, data-driven organization. Applicants should be prepared to engage with sophisticated technical concepts and contribute to architectural decisions that impact the reliability of hospital scoring systems used globally. The team values structured thinking, rigorous testing, and clear documentation as foundational practices for sustaining complex computation over time.