Platform Engineer - Full-Stack; Remote Spain

Full-stack Engineer – Payments (Spain) 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 Money Gram 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, and failure recovery in distributed financial flows.

• 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.
• Contribute to architecture decisions: write design docs, review peers’ proposals, and help the team make good long‑term calls.
• Participate in on‑call rotations (paid, once or twice per quarter) and own incidents on the systems you build.
• Help onboard and mentor newer engineers as the team grows.

• 4+ years building and maintaining production backend systems, ideally involving financial data, payments, or transaction‑critical infrastructure.
• Strong proficiency in Type Script or JavaScript (our primary stack), or another typed modern language with willingness to move quickly.
• Solid understanding of distributed systems fundamentals: idempotency, consistency guarantees, failure handling, async workflows.
• Fluent in English, written and spoken.

• Hands‑on integration experience with Stripe, Adyen, or similar payment processors.
• Exposure to stablecoin infrastructure, crypto payments, wallets, or cross‑chain systems.
• Experience operating financial systems in regulated environments.

Madrid office or full remote from Spain.

Full‑time, indefinite contract.

4+ years of experience.

• Extensive access to leading AI tools and subscriptions.
• Stock options program.
• Two performance reviews annually.
• Unlimited paid time off.
• Parental leave program.
• Company laptop + annual home‑office stipend.
• Daily stipend for in‑office meals and/or commuting.
• Three company‑paid off‑sites each year.
• Health and dental insurance fully covered.
• Flexible retribution with tax benefits through Cobee.

Crossmint is an equal‑opportunity employer committed to diversity and inclusion.