We are looking for a Senior Frontend Software Engineer with years experience, to help us design and ship secure, high-quality Web Applications and TypeScript SDKs. You will own features end-to-end - from APIs and SDK design to polished UIs - while working closely with backend, security and product teams. This role is ideal if you care deeply about security, code quality, and thoughtful engineering, and enjoy collaborating with others to build reliable systems.
What You Will Work On
1. Build web applications (Node.js, React) that showcase and validate our core product.
2. Integrate with REST APIs and collaborate closely with backend teams.
3. Own features from ideation -> development -> testing -> deployment, with security in mind at every step.
4. Configure, maintain, and optimize CI/CD pipelines for speed, reliability, and security.
5. Design, develop, and maintain TypeScript SDKs and libraries used by developers.
6. Write clear documentation for both internal teams and external users.
7. Participate in code reviews, pair programming, architecture decisions.
8. Contribute to TDD and E2E testing practices.
9. Troubleshoot and improve CI/CD workflows and developer experience.
Must-Have Qualifications
10. Strong experience with TypeScript, Node.js and React.
11. Experience with testing libraries such as jest, vitest, bun.test.
12. Experience designing and integrating REST APIs.
13. Knowledge of relational databases (e.g. PostgreSQL).
14. Understanding of asynchronous communication and/or event-driven systems.
15. Ability to understand, debug, and improve CI/CD pipelines.
Nice-to-Have (Not Required)
16. Deploying Next.js applications outside of Vercel (Docker is a big plus).
17. Experience with messaging platforms like Kafka or RabbitMQ.
18. Interest in learning Go to contribute to backend services.
19. Familiarity with cryptographic standards, mTLS, or secure communications.
20. Experience applying security standards such as OWASP SAMM.
Who You Are
You write secure, test-driven code, enjoy collaborating with teammates, and like helping others to grow. You are curious, pragmatic, and comfortable exploring new tools and technologies without losing sight of maintainability and security.
What will you do on your first 90 days
Days 0-30: Orientation & Foundations
21. Learn about CBDC, how Central Banks operate and how Filia® works.
22. Learn our culture, security mindset, and development practices.
23. Attend onboarding sessions on cryptography, secure code review, and incident response.
24. Set up your development environment and CI tooling.
25. Study product flows, architecture diagrams, and API specs.
26. Run our applications locally and explore the codebase.
27. Shadow senior engineers and attend product demos.
Days 31-60: Deepening Skills & First Contributions
28. Participate in secure coding workshops.
29. Pair program with a mentor.
30. Ship small features and bug fixes.
31. Contribute to E2E tests and CI/CD improvements.
32. Own a story and participate in a security-focused code review.
33. Document your work.
Days 61-90: Autonomous & Secure Contribution
34. Deliver a feature end-to-end (TDD -> review -> E2E -> deployment).
35. Propose new test cases and DX or performance improvements.
36. Optimize part of the CI/CD workflow (caching, automation, speed).
37. Mentor newcomers on secure coding fundamentals.
38. Help refine team processes and improve onboarding documentation.
Disclaimer
If this role sounds exciting to you but you don't meet every requirement, we still encourage you to apply. We value thoughtful engineers who care about security, quality, and continuous learning.
What’s great about working with us:
39. Culture and diversity: Join a people-oriented environment with different nationalities and a great team spirit, flat hierarchies (everyone speaks to everyone). Equal Opportunity Employer and LGBT+ friendly.
40. Team: An opportunity to shape our engineering culture and work with a passionate, mission-driven team. Collaboration with a diverse and very international team of outstanding people.
41. Global Collaboration: Work collaboratively with stakeholders around the globe.
42. Impactful Work: You will have the opportunity to participate in and shape a global lighthouse project in the domain of digital currencies.
43. Career Development: Benefit from continuous training, coaching, and talent development programs.
44. Social Benefits: Flexible compensation (transport tickets, training, private insurance), etc.
45. Own canteen: Take a break with our breakfast and lunch service: choose between a wide range of menus, salad desk, and sandwiches service. Nicely priced!
46. Work-Life Balance: Flexible working hours with the option for remote work (Mon–Thu 8:30 – 17:30 and Fri 8:30 – 15:30; 3 days of remote work).
47. Location: Sant Joan Despí. Easily accessible by public transport.