Senior Software Engineer II, Customer Experience

Kard is building commerce media infrastructure that connects financial institutions, financial-services platforms, and merchants through data and merchant-funded rewards. As our reach expands, we are building for a step-change in scale, and for opportunities ranging from more relevant rewards and marketer intelligence to new commerce and distribution models.

### About the Role

The Customer Experience (CX) team owns the systems that power Kard's end-to-end rewards experience: transaction matching and the cellar pipeline, offer ingestion and delivery (including partner integrations like Rewards Network and SEATED), the cell-based routing architecture, and the Support API that keeps our internal and partner-facing tooling running. As a Senior Software Engineer II, you'll operate at the center of this — designing and building the services that ingest, match, and settle transactions at scale, while helping the team raise its bar on operational readiness, testing, and documentation.

This role reports into the CX engineering team, with a strong focus on our issuer and partner-facing surface area, working alongside Support, Design, and Product through Kard's Shape Up-based pitch cycle. You'll drive pitches end-to-end, participate in on-call, and help the team keep pace with a fast-growing transaction volume and issuer surface.

### Responsibilities

• Architect and build scalable services across transaction matching, the cellar pipeline, and offer ingestion — new work defaults to Go and Postgres; existing services are a mix of TypeScript and MongoDB.
• Own features end-to-end through Kard's Shape Up cycle: discovery, pitch writing, implementation, testing, and production rollout, including a written launch/rollback plan for anything touching

transaction or offer data. * Actively participate in on-call, incident response, and IOC (interrupt/on-call) triage; drive root-cause fixes rather than one-off patches (e.g., ing