What are the responsibilities and job description for the Sr. Software Engineer – Backend position at PAYNOTE?
Location: Miami, FL (In-Office)
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 brand-new product, but it is backed by a 13 year established ISO, Seamless Chex, and led by players who have been in payments for decades. We are self-funded, which means we are not optimizing for arbitrary investor metrics. We 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 Senior Software Engineer to help lead the development and evolution of our backend systems. This is a high-trust role for a backend engineer who is strongest in Node.js, distributed workflows, data modeling, and operational reliability. You will own services that move sensitive financial data across modern payment workflows, while helping us build a durable engineering culture grounded in sound judgment, sustainable pace, and technical rigor.
Key Responsibilities
- Design and implement backend services and event-driven workflows using Node.js and AWS to support payment, reconciliation, and operational workflows.
- Enforce API idempotency and transaction-integrity safeguards across distributed payment workflows.
- Design data models and access patterns across DynamoDB and PostgreSQL to support high-concurrency payment workflows.
- Work across backend infrastructure, deployment, and observability concerns in a highly cross-functional engineering environment.
- Build observability and auditability mechanisms so financial events can be investigated, reconciled, and explained with confidence.
- Support reconciliation workflows that detect anomalies, breaks, and data drift across internal systems and external providers.
- Good architectural skills that can balance reliability, delivery speed, and long-term maintainability.
Required Qualifications
- 6 years of professional backend engineering experience, with substantial experience building and operating production systems in Node.js.
- Strong experience building backend APIs using GraphQL in production environments.
- Expertise in both NoSQL and relational data modeling, specifically DynamoDB and PostgreSQL.
- Working knowledge of AWS serverless architecture, including services such as Lambda, SQS, and EventBridge.
- Proven knowledge of eventual consistency, race conditions, retry safety, distributed coordination, and failure recovery in payment or similarly high-stakes systems.
- Experience designing systems with strong auditability, observability, operational discipline, and automated testability.
- Clear communication skills and the ability to operate with a high degree of agency, proactively move work forward, and unblock progress in a senior engineering role.
- Ability to work full-time from our North Miami office.
Preferred Qualifications
- Prior experience building or maintaining double-entry accounting systems, payment gateways, or financial transaction platforms.
- Familiarity with security and audit requirements relevant to financial systems, including frameworks such as PCI-DSS, SOC 2, or SAQ A-EP.
- Experience working with AWS CDK, CloudFormation, CI/CD pipelines, or infrastructure as code in a backend-heavy environment.
- Confidence in using modern AI tools to accelerate the SDLC, with good judgment around where they improve speed, quality, and developer leverage.