Senior Software Engineer, Back-End (Payments)

3 months ago

Remote, United StatesSenior

Base Salary

$141k - $229k/yr

Responsibilities

Design, implement, and maintain multi-gateway payment integrations, including Stripe and PayPal, with abstractions supporting gateway changes.
Own payment flows end-to-end from initiation through settlement, refunds, and reconciliation.
Develop backend payment services and APIs in C#/.NET.
Build customer-facing checkout and payment-management experiences using React, Svelte, and TypeScript.
Apply PCI-DSS practices, tokenization, idempotency, retries, audit controls, and resilient design patterns.
Design and operate distributed, event-driven services on AWS and Kubernetes.
Implement metrics, tracing, alerting, dashboards, and monitoring to support availability and incident response.
Partner with product, design, security, compliance, Payments, Marketplace, Grading, Vault, and platform teams.
Use AI-assisted development tools throughout planning, coding, review, debugging, and delivery.

6+ years of engineering experience designing, shipping, and scaling products with measurable business impact.
Ideally 2+ years operating as a Senior IC or equivalent technical leadership level at a high-growth company or scaled consumer platform.
Deep backend expertise in C# and .NET, including complex APIs, asynchronous patterns, and distributed-system data consistency.
Experience building responsive frontend experiences with React, Svelte, and TypeScript.
Experience with relational and NoSQL databases, including schema design and efficient queries.
Experience with payment or fintech systems, gateway integrations, idempotency, webhooks, tokenization, and PCI compliance.
Experience designing and operating microservices and Kafka-based event-driven architectures on Kubernetes and AWS.
Experience with observability tools such as Datadog, including dashboards, monitoring, alerting, and distributed tracing.
Familiarity with Agile/Scrum methodologies.
Strong written and verbal communication, analytical and troubleshooting skills, ownership, and ability to influence without direct authority.
Passion for collecting is a plus.

Medical, dental, and vision insurance for eligible full-time employees.
Fertility, commuter, and educational assistance benefits for eligible full-time employees.
401(k) matching plan.
Flexible time off for salaried employees.
Ten company-paid holidays for regular full-time employees.
Employee discounts on select grading services.
Flexible hours and varying schedules on many teams.
Team celebrations, holiday events, and team-building activities.
Candidates within a one-hour commuting distance of the office may be expected to work onsite most of the time; remote and hybrid arrangements are indicated in the posting.

1,001-5,000 employees