Senior Software Engineer

IXOPAY is the enterprise-grade global payment infrastructure platform built for the era of agentic commerce. They are seeking a Senior Software Engineer to own the backend architecture for a next-generation AI-first payment orchestration platform, designing and building core systems that unify various functionalities.

Responsibilities:

• Architect and build the capability-aware Routing Engine — selecting downstream connectors based on instrument metadata (card brand, currency, BIN, transaction type) with fallback logic and structured routing events per transaction
• Build the Configuration Service — encrypted credential store, CRUD API, and tenant-scoped routing targets with a schema extensible to new plugins without migrations
• Design and publish MCP-enabled APIs that allows AI agents to query, simulate, and propose changes — with a human-in-the-loop approval gate for high-impact changes
• Develop and maintain agentic anomaly detection across routing behavior and transaction patterns, feeding signals into a routing recommendation engine
• Collaborate with product and the AI agent team to translate business requirements into durable, observable backend services
• Mentor the Junior Engineer through code review, design discussions, and technical guidance

Requirements:

• 5+ years of professional software engineering experience building production backend services
• Strong backend proficiency in C#/.NET — our primary stack is .NET 10
• Experience designing APIs consumed by external systems or agents — REST, event-driven, or both
• Solid understanding of relational databases, data modeling, and schema design for high-throughput financial systems
• Background in payment systems, PSP integrations, tokenization infrastructure, or equivalent fintech backend complexity
• Familiarity with security patterns relevant to payment data: credential encryption, HMAC signing, token handling, and secrets management
• Comfort with cloud infrastructure — we run on Azure (App Configuration, Key Vault)
• Strong communication skills and the ability to define architectural direction clearly for a small, collaborative team
• Experience integrating with LLM APIs or building MCP-compatible services
• Prior work with routing engines, rules-based decisioning systems, or capability registries
• Platform or SDK design experience — defining contracts and interfaces that other developers build against
• Familiarity with adapter/plugin architectures for integrating third-party payment providers
• Exposure to AI coding tooling and agent-assisted development workflows
• Background in PCI DSS compliance engineering — scoping, segmentation, and minimizing cardholder data exposure
• Experience with network tokenization, credential-on-file optimization, or Account Updater workflows