Staff Backend Engineer (Financial Ledger)

This position is listed on behalf of a partner company, who manages all applications and next steps. Our partner is looking for a Staff Backend Engineer (Financial Ledger) based in Poland. This role sits at the core of a rapidly evolving financial infrastructure powering a modern travel-tech SaaS platform. You will take ownership of a critical backend system responsible for financial accuracy, including revenue recognition, payments, ledger events, and profit calculation across a distributed environment. Rather than building from scratch, you will join an active evolution phase where foundational architecture already exists and is being expanded toward a more scalable and robust V2. The position requires deep technical leadership combined with hands‑on engineering, ensuring the correctness and reliability of financial flows that directly impact business operations. You will collaborate closely with engineering and finance stakeholders to define invariants, validate system behavior, and guide architectural decisions. This is a high‑impact role where your work becomes the backbone of financial truth for a growing SaaS ecosystem. Accountabilities Take technical ownership of the Financial Core system, guiding its evolution, challenging assumptions, and aligning architecture with long‑term financial scalability. Ensure system integrity by validating lifecycle flows, reconciliation logic, and financial correctness across distributed services. Design and maintain ledger‑style financial models, including revenue recognition, cost allocation, and multi‑party transaction flows. Improve and enforce strict financial invariants within an event‑driven architecture to ensure deterministic and auditable outcomes. Collaborate with finance and engineering leadership to translate business rules into robust technical implementations. Lead the evolution of a live production system, identifying gaps in current architecture and driving improvements toward future iterations. Support system reliability and scalability across payment, billing, and financial reporting domains. Contribute hands‑on to backend development while shaping long‑term architectural direction. Requirements 8+ years of backend engineering experience with strong ownership of financial, billing, or transactional systems. Proven experience building or maintaining financial platforms such as payment systems, billing engines, ERP solutions, or subscription infrastructure. Deep expertise in ledger systems, reconciliation mechanisms, and ensuring deterministic financial correctness. Strong understanding of financial concepts such as revenue recognition, liabilities, cost structures, and multi‑party money flows. Experience evolving complex production systems in active environments without disrupting existing functionality. Hands‑on engineering mindset with the ability to both design architecture and implement critical backend systems. Strong proficiency with Python and relational data modeling (PostgreSQL preferred). Experience with event‑driven architectures and distributed systems in cloud environments (AWS preferred). Ability to handle complex financial scenarios including multi‑currency, taxation logic, and settlement flows. Benefits Competitive compensation aligned with senior‑level backend engineering roles Fully remote‑friendly work environment Opportunity to own a mission‑critical financial system at the core of a SaaS transformation High‑impact technical leadership role with significant architectural autonomy Exposure to complex financial systems and large‑scale distributed architectures Collaborative environment working closely with engineering and finance stakeholders Modern cloud‑based stack (AWS, event‑driven systems, Python‑based services) Long‑term technical ownership of a foundational business system #J-18808-Ljbffr