Senior Software Engineer, Backend

Payabli; Fort Lauderdale (FL); On-site; USD 140,000 - 180,000; Full time

Job summary

Payabli in the United States (Fort Lauderdale) is seeking a Senior Software Engineer, Backend to design and build the backend of our payments platform. You will shape scalable services powering payment routing, connectors, and platform configuration, collaborating with product, AI, and engineering teams.

You will lead by example, mentor engineers, and own full lifecycle from requirements through deployment.

Qualifications

• 5+ years of experience building production backend services.
• Strong experience with C# and the .NET ecosystem.
• Experience in Payments/FinTech or high-volume transaction environments.
• Experience designing RESTful and/or event-driven APIs.
• Knowledge of relational databases and distributed systems.

Responsibilities

• Design, build, and maintain scalable backend services using C#/.NET.
• Develop core infrastructure powering payment routing, connectors, and platform configuration.
• Design secure, extensible APIs for customer-facing apps, integrations, and AI workflows.
• Build reliable services capable of high-volume payment processing with resilience.
• Lead architecture discussions, standards, and performance improvements.
• Mentor engineers and promote backend quality across the team.
• Own full lifecycle from requirements to deployment.

Skills

C#

.NET

Payments

FinTech

REST APIs

Event-driven

Relational databases

Cloud-based apps

Technical leadership

Communication

Job description

We are looking for a Senior Software Engineer, Backend to join our team and help build the backend of Payabli's interfaces and integrations that sit between complex financial infrastructure and the humans who use it every day – merchant dashboards, onboarding flow, embeddable components, and white-label experiences consumed by our platform partners and their end users.

In this hands-on role, you'll design and build the services that power intelligent payment routing, connector management, token intelligence, and platform configuration. You'll work on complex, high-scale systems that enable merchants to optimize payment performance while building secure, extensible infrastructure for the future of payments.

You'll collaborate closely with Product, AI, and Engineering teams, mentor junior engineers, and play a key role in shaping the architecture of a platform used by substantial enterprise customers.

What you will Do:

• Design, build, and maintain scalable backend services using C#/.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
• Raise the bar: Lead code reviews, champion backend standards, and drive architectural decisions that keep the codebase healthy as we scale.
• Multiply the team: Mentor engineers around you and elevate backend engineering quality across the organization through pairing, documentation and leading by example.
• Own the full lifecycle: Work across requirements, implementation, testing, and deployment. We don't throw things over the wall here.

What we are looking for:

• 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.