Senior Payments Engineer — Acquiring & Payment Processing

Overview

Senior Payments Engineer responsible for owning and scaling backend systems for Sezzle’s acquiring and payment-processing stack.

What you'll do

• Design and build backend services in Golang to integrate with payment processors, gateways, and card networks.
• Own end-to-end money-movement flows including authorization, capture, settlement, refunds, reconciliation, and dispute handling.
• Build idempotent, fault-tolerant, auditable transaction processing in distributed architectures.
• Operate within PCI DSS scope using tokenization and handling payment data and 3DS/SCA flows where applicable.
• Instrument and monitor payment health metrics like authorization/decline rates, processor performance, latency, and settlement accuracy.
• Use AI tooling (Claude and equivalent LLMs) to accelerate design, coding, research, testing, and documentation.

What you'll need

• 8+ years of experience for a senior development role.
• Demonstrated experience working with Claude or equivalent LLM tools is required.
• Strong Go preferred, or comparable backend experience in Python via REST APIs.
• Hands-on integration experience with payment processors/gateways/acquiring systems.
• Familiarity with payments fundamentals such as authorization vs. settlement, tokenization, idempotency, reconciliation, and chargebacks/disputes.
• Experience with distributed, cloud-based architectures including transactional outbox and/or queuing tools (Kafka, SQS, RabbitMQ).
• Bachelor’s degree in Computer Science, Engineering, or a related field.

Details

• Location: Brazil (Remote).
• Tag includes “Full-time”.