Senior Payments Engineer — Acquiring & Payment Processing

Design and build backend services in Golang that integrate with payment processors, gateways, and card networks

Own critical money-movement flows end to end: authorization, capture, settlement, refunds, reconciliation, and chargeback/dispute handling

Build idempotent, fault-tolerant, auditable transaction processing within a distributed architecture (transactional outbox patterns; queues such as Kafka, SQS, or RabbitMQ)

Operate within PCI DSS scope — tokenization, network tokens, secure handling of payment data, and 3DS/SCA flows where applicable

Instrument and monitor payment health: authorization/decline rates, processor performance, latency, and settlement accuracy, driving continuous improvement

Use AI tooling (Claude and equivalent LLMs) as part of your daily workflow to accelerate design, coding, research, testing, and documentation — within Sezzle's security and data-handling policies

Mentor engineers and help raise the bar across the team

Demonstrated experience working with Claude or equivalent large language model tools is required; candidates must be comfortable leveraging AI to enhance productivity, research, and communication.

Direct experience with payments acquiring ecosystem like; Adyen, Stripe, Marqeta, Fiserv, etc.

Exposure to PCI DSS, 3DS/SCA, network tokenization, or payments compliance

SQL-based RDBMS through an ORM

Observability platforms (Prometheus, Datadog, New Relic) for production instrumentation and alerting

DevOps / CI/CD pipeline experience; containerized microservices on Kubernetes / AWS

A track record of shipping commercial payment APIs and prioritizing based on stakeholder/customer feedback

Sezzle runs an AI-first product and engineering culture — we start projects in Claude and expect engineers to use AI to move faster and think more rigorously. In a payments environment, we do this responsibly : AI tools accelerate how we design, build, and document, but cardholder data, credentials, and secrets never leave our secured environment. We're looking for someone who treats AI fluency and secure-by-default engineering as two sides of the same skill.

You have relentlessly high standards - many people may think your standards are unreasonably high. You are continually raising the bar and driving those around you to deliver great results. You make sure that defects do not get sent down the line and that problems are fixed so they stay fixed.

You’re not bound by convention - your success—and much of the fun—lies in developing new ways to do things

You need action - speed matters in business. Many decisions and actions are reversible and do not need extensive study. We value calculated risk-taking.

You earn trust - you listen attentively, speak candidly, and treat others respectfully.

You have backbone; disagree, then commit - you can respectfully challenge decisions when you disagree, even when doing so is uncomfortable or exhausting. You have conviction and are tenacious. You do not compromise for the sake of social cohesion. Once a decision is determined, you commit wholly.

You deliver results - you focus on the key inputs and deliver them with the right quality and in a timely fashion. Despite setbacks, you rise to the occasion and never settle.

Languages: Golang, Typescript, Python

Frontend: Typescript - React and React Native

Backend: Golang

Database: MySQL, Postgres, Elasticsearch

DevOps & Cloud: AWS, Kubernetes

Version Control: Git

CI/CD: Gitlab

Testing: Developer-driven, focus on automated unit, integration, and end-to-end tests

Sezzle is focused on using open source, and we build what we can before buying!

At Sezzle, we are more than just brilliant engineers, passionate data enthusiasts, out-of-the-box thinkers, and determined innovators; we are skilled musicians, yogis, cyclists, chefs, golfers, dog-lovers, and rock-climbers. We believe in surrounding ourselves with not only the best and the brightest individuals, but those that are unique and purpose-driven in all that they do. Our culture is not defined by a certain set of perks designed to give the illusion of the traditional startup culture, but rather, it is the visible example living in every employee that we hire.

#Li-remote #Full-time