Senior Software Engineer – Full Stack

The Company Background

Paynote is a next-generation payments platform designed to bridge legacy financial systems and modern payment infrastructure. We are building a platform that combines traditional payment rails with crypto-based infrastructure to enable faster settlement, stronger merchant protections, and more efficient global payouts.

Paynote is a new product built out of Seamless Chex - a payments ISO with 10+ years in the industry. We are fully self-funded, and are focused on building useful systems, shipping customer-ready improvements quickly, and creating long-term value for customers.

About the Role

We are seeking a Full Stack Senior Software Engineer to contribute across our entire product stack. This role is a strong fit for an engineer who is comfortable building customer-facing experiences, backend APIs, and data-driven workflows in a highly collaborative environment. You will work on systems that support real payment operations while growing your ability to ship reliable software in small, well-tested increments.

Key Responsibilities

• Build and maintain integrations and features across the full stack, from frontend interfaces to backend services with an emphasis on defensive programming, strict typing, and validating data at system boundaries.
• Develop React-based interfaces using component-driven UI patterns and modern frontend frameworks.
• Implement backend functionality in Node.js to support payment, reconciliation, merchant, and operational workflows.
• Contribute to data models and access patterns across DynamoDB and PostgreSQL.
• Help improve application reliability through logging, observability, and thoughtful error handling.
• Support event-driven workflows and integrations that use AWS services such as Lambda, SQS, EventBridge, Kinesis, and S3.
• Work closely with product and engineering teammates to deliver customer-ready improvements in small, high-quality increments.
• Contribute to a shift-left engineering culture that emphasizes automated testing, proactive ownership, and continuous improvement.
• Own the code quality of your work, treating testing as part of development.

Required Qualifications

• 3 - 7 years of professional software engineering experience, including experience shipping production web applications.
• Strong proficiency in TypeScript, with deep practical experience across both frontend and backend environments.
• Comfort working in a full-stack capacity, moving fluidly between React-based UIs and Node.js services within a shared codebase.
• Experience building and consuming APIs, working with asynchronous flows, and debugging production issues.
• Familiarity with modern frontend development patterns, including stateful UI, routing, component-based design system.
• Working knowledge of relational and NoSQL databases, ideally PostgreSQL and DynamoDB.
• Familiarity with cloud-based development workflows, preferably in AWS environments.
• Experience writing automated tests and a clear preference for validating quality through engineering practices.
• Clear communication skills and the ability to operate with a high degree of agency.
• Ability to work full-time from our North Miami office.

Preferred Qualifications

• Experience with full-stack TypeScript frameworks (e.g., Next.js, Remix, or similar) and comfort navigating shared conventions across layers of the stack.
• Exposure to event-driven systems, serverless architecture, or infrastructure as code.
• Experience working on financial systems, payment products, or other high-trust transactional software.
• Confidence in using modern AI tools to accelerate the SDLC, with good judgment around where they improve speed, quality, and developer leverage.