Full-stack Engineer - Payments Spain

About Crossmint

Crossmint is the leading enterprise-grade, all-in-one stablecoin and wallet infrastructure platform enabling fintechs and enterprises to integrate stablecoin rails and smart wallets with speed, compliance, and scale.

Backed by Ribbit Capital, Franklin Templeton, NYCA, First Round, and Lightspeed Faction, with $23.6M raised in 2025. Trusted by more than 40,000 clients including global leaders such as MoneyGram, WireX, Toku, and more, Crossmint provides embedded smart wallets, on/offramps, cross-chain stablecoin orchestration, tokenization, and other blockchain primitives through simple, developer-friendly APIs that integrate in minutes and scale to millions of users.

In January 2026, Crossmint secured MiCA authorization from Spain's CNMV, becoming one of a select few stablecoin infrastructure providers fully licensed to operate across all 27 EU member states and held to the same regulatory standards as traditional financial institutions. Crossmint also powers the Republic of the Marshall Islands' first digital UBI program, backs MoneyGram's new stablecoin cross-border experience launching in LATAM, and recently partnered with WireX to expand multichain stablecoin payment infrastructure to non-EVM networks like Stellar.

The future of finance is stablecoin-native. Crossmint makes it easy to get there.

Location

We have offices in Madrid, and we are also open to a full remote setting from Spain.

Type of employment

Full-time, indefinite contract.

Seniority

4+ years of experience.

About the Role

The Payments team owns the infrastructure that moves real money through Crossmint , including on/offramps, cross-chain stablecoin flows, and the payment rails that clients like MoneyGram and WireX build on top of. This is not a billing or internal tooling role. You will be working on systems where correctness, uptime, and consistency actually matter, across multiple providers, chains, and fiat currencies. The challenges are real: Multi-provider routing, idempotency at scale, reconciliation across async settlement windows, failure recovery in distributed financial flows.

What You Will Do

Design and build payment infrastructure: processor integrations, transaction pipelines, settlement and reconciliation workflows, and the APIs clients depend on.

Own critical financial flows end to end, including failure modes, retry logic, state management, and edge cases that matter in production.

Work across the stack: backend-heavy, but you will contribute to APIs, dashboards, and the interfaces clients use to interact with payment systems.

Ensure data integrity across providers and chains: balances, transaction states, and audit trails that stay consistent even when third-party systems don't.

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