Senior Software Engineer, Backend

Payabli•Miami, FL

About The Position

Payabli is seeking a Senior Software Engineer, Backend to join their team. This role involves building the backend of Payabli's interfaces and integrations, which connect complex financial infrastructure with users. The engineer will design and build services for intelligent payment routing, connector management, token intelligence, and platform configuration. They will work on high-scale systems to optimize payment performance and build secure, extensible infrastructure for the future of payments. The position requires collaboration with Product, AI, and Engineering teams, mentoring junior engineers, and contributing to platform architecture. The company is a next-generation Payments Infrastructure and Monetization Platform for vertical software companies, backed by leading fintech investors.

Requirements

5+ years of experience building production backend services.
Strong experience with C# and the .NET ecosystem.
Strong experience in Payments, FinTech, or other high-volume transaction processing environments.
Experience designing and building RESTful and/or event-driven APIs.
Strong understanding of relational databases, data modelling, and distributed systems.
Experience building secure, scalable cloud-based applications.
Excellent problem-solving, communication, and collaboration skills.
Ability to provide technical leadership while remaining hands-on in development.

Responsibilities

Design, build, and maintain scalable backend services using C# and .NET.
Develop the core infrastructure that powers payment routing, connector management, and platform configuration.
Design secure, extensible APIs that support both customer-facing applications, direct integrations and AI-powered workflows.
Build reliable, observable services that process high-volume payment transactions with performance and resilience in mind.
Contribute to platform architecture, engineering standards, and technical decision-making.
Continuously improve system performance, security, reliability, and developer experience.
Collaborate closely with other service owning teams to integrate via APIs and real-time data streams, ensuring seamless data flow across the stack & overall platform.
Lead code reviews, champion backend standards, and drive architectural decisions that keep the codebase healthy as we scale.
Mentor engineers around you and elevate backend engineering quality across the organization through pairing, documentation and leading by example.
Work across requirements, implementation, testing, and deployment.
Optimize for performance, accessibility, and cross-browser compatibility.