Senior Full-Stack Engineer

Our client is an early-stage financial technology company building a global, non-custodial consumer application that allows users to hold, spend, and transfer money across borders without relying on a traditional bank.

The platform is powered by blockchain technology but is designed to feel familiar and accessible to mainstream users. It removes much of the complexity traditionally associated with cryptocurrency and self-custody while allowing users to remain in control of their funds.

The company serves customers internationally and is currently focused on expanding its presence among younger consumers in the United States.

Backed by leading investors, the business has significant financial runway and operates with a small, highly technical engineering team that values speed, product quality, and ownership.

About the Role

We are looking for a Senior Full-Stack Engineer to join as one of the company’s key founding-level engineering hires.

This role is suited to a senior generalist engineer who can own features from end to end across the company’s technology stack, including backend services, APIs, application development, and external integrations.

The engineering team operates under a shared-ownership model, meaning engineers are not restricted to one technical layer. The successful candidate will be expected to contribute wherever necessary while maintaining a high standard of quality and delivery speed.

The role overlaps significantly with mobile product engineering and is particularly suitable for engineers who are comfortable moving between backend, frontend, and application development.

Own and deliver product features from end to end across the technology stack.

Build backend services and APIs using Node.js and Type Script.

Contribute to frontend and mobile application development.

Develop and maintain integrations with external services and blockchain infrastructure.

Write clean, reliable, and scalable Type Script.

Work directly with founders, product, and design stakeholders.

Move quickly from product concept to production release.

Make pragmatic architectural decisions.

Help establish engineering standards, development practices, and tooling.

Contribute to product quality and polish across all customer touchpoints.

Debug and resolve complex product and technical problems across multiple layers of the stack.

5+ years of professional software engineering experience shipping production software.

Strong full-stack engineering capability across backend and frontend development.

Ability to learn and adopt new technologies quickly.

Experience owning product features throughout the full development lifecycle.

Strong product mindset and attention to customer experience.

Ability to work independently within a fast-moving early-stage startup.

Willingness to relocate to and work on-site in Madrid or Miami.

Experience with React.

Experience with React Native.

Experience with EVM, Solidity, blockchain, or cryptocurrency products.

Experience with AWS.

Experience with Kubernetes.

Experience with Terraform.

Consumer product or fintech experience.

Early-stage startup experience.

Experience helping establish engineering culture, technical standards, or development tooling.

The strongest candidates are likely to have founded a company or worked within an early-stage startup where they developed a high-ownership operating mindset.

Experience with in cryptocurrency-native products or leading consumer-fintech companies is valuable. However, strong engineers from smaller or lesser-known businesses will also be considered.

The company is particularly interested in senior, product-minded engineers who care deeply about the customer experience…