Full-stack Engineer - Payments (Spain)

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.
• 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.

What We Are Looking For

Must-haves

• 4+ years building and maintaining production backend systems, ideally involving financial data, payments, or transaction-critical infrastructure.
• Strong proficiency in TypeScript 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.

Strong plus

• 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.

Please keep in mind: This is the full list of everything we’re looking for. You don’t need to check every single box to be a strong candidate, and having a good number of these would already indicate a solid fit for the role.

Why Join Crossmint?

The Payments team sits at the core of what Crossmint does. The infrastructure you build will be used by enterprises moving real money through stablecoin rails, in one of the first companies fully licensed under MiCA to operate across the EU. The team is small, the ownership is high, and the problems are genuinely hard. If you want to work on financial infrastructure that matters, without layers of process slowing you down, this is the role.

Benefits

• Extensive access to leading AI tools and subscriptions, with AI actively encouraged and integrated into daily workflows.
• Stock options program.
• We conduct two performance reviews annually. The first addresses performance ratings, bonuses, and promotions. The second encompasses these elements along with salary adjustments reflecting inflation and market conditions.
• Unlimited Paid Time Off.
• Parental Leave program.
• Company laptop + Annual home office and productivity stipend.
• Daily stipend for in-office meals and/or commuting to the office.
• Three company-paid off-sites each year. Recent ones include: Miami, Lisbon, Medellín, Panamá.
• Health + Dental insurance fully covered by Crossmint.
• Flexible retribution with tax benefits through Cobee.

Our Principles

• Results and delivery: Ship high quality work fast.
• Build for the long term: Build scalable, secure, and reliable solutions. Use AI.
• Extreme Ownership: Be an effective Directly Responsible Individual (DRI). Be proactive.
• Be a team player: Be an effective and kind colleague providing credible challenge. Be present and reliable.

*Talent research indicates that women are often less inclined than men to apply for a role unless they have experience in 100% of the listed skills. However, this list is only a guide. We welcome your application even if you feel you meet around 75% of the requirements. At Crossmint, we believe skills can be learned, and diversity makes us stronger.

We work to foster a respectful environment where each person can be their authentic self, free from harassment, racism, and any form of discrimination. We proudly uphold our commitment to diversity and inclusion as an equal opportunity employer, and this policy applies to all employment practices within our organization.

Please note that Crossmint never conducts AI-based interviews, and all of our processes include an initial video call with a team member. Crossmint will not request your personal identification documents or any payment at any point during your interview process. Please stay vigilant about potential fraud. If you receive an email that claims to be from Crossmint but ends with any domain other than @crossmint.com, @crossmint.io or @paella.dev, it is not from us. We own these three domains listed before, and they are the only legitimate ones.

Please let our Talent Team know if you need any assistance completing any forms, or participating in the process.*

Who will be in contact with you

Our People Ops team will be joining you throughout the entirety of the interview and onboarding processes. Feel free to reach out if you need anything!

• Adolfo Fernández - Recruitment & People Ops
• Gloria Alogo - People Ops, Onboarding & Benefits
• Jon Eichhorn - Head of HR

⚠️ Please note that these are the only members of our People Ops team. Please remain vigilant and watch out for impersonators.

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