Design and own end-to-end architecture for mission-critical payment services and organization related systems, spanning real-time rails, API gateways, tokenisation frameworks, and settlement infrastructure ensuring scalability, fault tolerance, and regulatory compliance at national scale. Translate complex business and compliance requirements into technically rigorous, vendor‑neutral architectural decisions. Define and enforce architecture standards, patterns, and guardrails across engineering squads without direct management authority. Lead technical due diligence on vendor and third‑party integrations, evaluating against security, performance, and interoperability criteria. Collaborate with product, engineering, risk, and compliance stakeholders to align architecture with strategic roadmaps. Produce architecture decision records, reference architectures, and threat models that serve as institutional knowledge. Drive the reduction of technical debt through structured remediation...