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# Senior Software Engineer, Card Solutions (Backend-Focused/Partner Integration)

- **Company:** Reap Inc
- **Location:** United States (Remote available)
- **Experience:** Expert
- **Contract:** Permanent contract
- **Skills:** Java (Programming Language), Application Programming Interfaces (APIs), Amazon Web Services, Code Review, Distributed Systems, Fault Tolerance, Fraud Prevention and Detection, Node.Js, Service-Oriented Architecture, Software Engineering, Systems Architecture, Tokenization, TypeScript, Transaction Processing (Computing), Backend, Build Management, NestJS, Golang
- **Published:** September 30, 2026
- **Apply:** https://arc.dev/remote-jobs/j/redirect/po42f4fgxc

## About the Role

* 6+ years of software engineering experience, ideally in fintech, infrastructure, or platform teams
 * Experience building backend systems in a typed language (e.g., TypeScript, Java, Go, etc.)
 * Solid grasp of distributed systems concepts: async processing, retries, observability, eventual consistency
 * Strong judgment in balancing correctness, performance, and maintainability
 * Ability to collaborate in cross-functional teams and communicate technical tradeoffs effectively
 * Comfortable working in a fast-paced, evolving product environment

Nice to Have

 * Experience in card networks, 3DS, PCI, tokenization, or chargeback systems
 * Built systems involving compliance or regulatory constraints
 * Familiarity with Reap's stack: TypeScript, Node.js, NestJS, AWS
 * Worked in high-growth startups or platforms with external APIs

## Description

As a Senior Software Engineer in the Card Engineering team, you'll help build the foundation of Reap's card platform-designing, developing, and operating services that power card transactions, fraud detection, card lifecycle management, and developer-facing APIs.

You'll be a key contributor in a high-ownership, cross-functional environment, working closely with product managers, designers, compliance, and other engineers. From authoring transaction workflows to implementing scalable event-driven services, your work will shape the core infrastructure used by clients, partners, and developers globally.

This role is ideal for engineers who enjoy solving real-world financial problems at scale, care deeply about system correctness and resiliency, and thrive in fast-moving, collaborative teams.

What You'll Do

 * Design and build backend services for card transaction processing, fraud detection, and/or card program management
 * Contribute to system architecture and technical decision-making with a focus on performance, fault tolerance, and maintainability
 * Collaborate with cross-functional stakeholders (Product, Risk, Finance, Compliance) to deliver robust, compliant financial systems
 * Write clean, observable, and well-tested code in a service-oriented architecture
 * Participate in code reviews, incident response, and ongoing reliability improvements
 * Help evolve our engineering practices, tools, and system designs as we scale