Sr. Software Engineer – Backend & Cloud Infrastructure

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 13+ year old ISO, SeamlessChex, 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. This is a high-trust role for a backend engineer who is strongest in AWS infrastructure, distributed workflows, and operational reliability. You will own systems 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 AWS serverless architectures using Node.js, Lambda, EventBridge, and SQS to support complex payment and reconciliation workflows.
• Enforce strict API idempotency and transaction-integrity safeguards across distributed payment workflows.
• Architect data models and access patterns across DynamoDB and PostgreSQL to support high-concurrency payment workflows.
• Manage infrastructure through AWS CDK and CloudFormation, treating infrastructure as a core software engineering responsibility.
• Build centralized observability and auditability mechanisms so every financial event can be investigated, reconciled, and explained with confidence.
• Orchestrate reconciliation workflows that detect anomalies, breaks, and data drift across internal systems and external providers.
• Partner closely with leadership to make sound architectural decisions that 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.
• Prior experience building or maintaining systems in the payments platform / FinTech space.
• Deep understanding of AWS serverless architecture with practical experience managing concurrency, cold starts, retries, failure handling, and event-driven anti-patterns.
• Expertise in both NoSQL and relational data modeling, specifically DynamoDB and PostgreSQL.
• Possess a command of infrastructure as code, especially AWS CDK.
• 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, and 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

• Familiarity with security and audit requirements relevant to financial systems, including frameworks such as PCI-DSS, SOC 2, or SAQ A-EP.
• Experience owning infrastructure, deployment, and reliability concerns in a small, high-accountability engineering environment.
• Confidence in using modern AI tools to accelerate the SDLC, with good judgment around where they improve speed, quality, and developer leverage.