Senior Full Stack Engineer

About Us At Félix , we're building the financial ecosystem for Latin immigrants in the U.S., starting with a revolution in remittances. Our core product is an AI-powered chatbot built on WhatsApp, allowing our users to send money home as easily as sending a text message. We leverage cutting-edge technology like AI, blockchain, and stablecoins to make cross-border payments faster, more affordable, and more accessible than ever before. We are a hyper-growth Series B company, backed by over $100 million in funding from top-tier global investors, including QED, Castle Island, Switch Ventures, HTwenty, Monashees, and General Catalyst Customer Value Fund. This isn't just about the numbers; it's a testament to the trust our investors have in our vision and our team. Additionally, Félix was selected as an “Endeavour Entrepreneur” and was a recipient of the CrossTech Fintech Startups Award. We are a group of extremely talented and dedicated high-performers, united by our shared obsession with a single goal: empowering our customers. We are all owners of Félix, driven by a bias for action and a true experimentation spirit to get shit done with urgency and focus. Joining Félix means you will be part of a team building a legacy, a company that will outlive us all. This is a rare opportunity to apply your skills to a deeply meaningful mission—serving a community that has been underserved for too long. We are a team that is fiercely loyal to each other, where radical transparency and constructive feedback are how we grow and push for excellence. We are bold, we care less about what others are doing, and more about creating sustainable value and a product that truly makes our users' lives better. We are building the future, today. About the Role We are transitioning our core operational capabilities from third-party low-code solutions to a robust, highly scalable, in-house ecosystem. As part of the CX Platform team, you will own the construction of the operational modules that power our daily business, building features end-to-end from the React UI down to the Node.js services that aggregate and protect our data. You will own the modules, screens, and APIs that the CX team relies on every day, designing, building, and shipping them end-to-end. Your work has a direct, measurable impact: every feature you ship reduces handling times, removes friction, and gives our operators superpowers. If you love taking features from idea to production without artificial silos between frontend and backend, and you get satisfaction from shipping tools that real humans rely on to do real work, this is your place. Technology Stack: We care more about strong engineering fundamentals than expertise in any specific tool. If your foundations are solid, picking up adjacent technologies should be second nature. That said, here is the stack you will be working with day to day: Front-end: Advanced React, TypeScript, Component-Driven UI, Modular CSS Architectures. Back-end: Node.js + TypeScript, REST API design, secure aggregation layers, Backend-for-Frontend (BFF) patterns. Data Layer: Relational data modeling (PostgreSQL or similar), schema design, query optimization, transactional integrity. Security & Access: RBAC, secure handling of sensitive data, strict environment isolation. Tooling & Delivery: Modern build tools and bundlers, Git workflows, CI/CD pipelines. Responsibilities End-to-End Feature Ownership: Build complete operational modules, from the React UI down to the Node.js services and data models that power them. You own the feature, not just a layer of it. Module Development: Design and ship the modules that live on top of our CX platform: high-density data views, complex operational workflows, and internal tools that drastically reduce cognitive load for our operators. Secure Integration Layer: Implement intermediary layers (BFFs, aggregators) that consume internal microservices and external providers, standardize payloads, and enforce strict authorization rules before data reaches the client. Operational Efficiency: Collaborate shoulder-to-shoulder with core business stakeholders to deeply understand their daily workflows, then translate that understanding into technical solutions that materially reduce handling times. Engineering Craft: Champion clean patterns, pragmatic design, and a high quality bar across the modules you ship. Mentor peers and elevate the broader engineering culture. Requirements 5+ years of experience as a Software Engineer in a fast-paced, dynamic environment. Fluent or advanced English (Upper-intermediate is fine, as long as you can communicate clearly in a technical setting). Advanced React & UI Engineering: Deep understanding of React and solid foundations in web standards (HTML/DOM, CSS, HTTP). TypeScript proficiency is expected. Solid Node.js / Backend Skills: Proven ability to design and build well-structured REST APIs in Node.js. Strong grasp of API design, service boundaries, error handling, and clean backend patterns. Data Modeling: Comfortable designing relational schemas, writing performant queries, and reasoning about transactional integrity. Security & Authorization: Hands-on experience implementing authentication and authorization flows, especially Role-Based Access Control (RBAC) over sensitive data. Aggregation / BFF Patterns: Ability to design backend-for-frontend or aggregation layers that consume multiple microservices and expose a clean, secure surface to the client. Problem Solving: Excellent problem-solving skills with a balance of creative UI implementation and strict engineering rigor on the backend. Nice to have (highly desirable): Technical Leadership: Track record of mentoring engineers, raising the bar in code reviews, and influencing architectural decisions beyond your immediate scope. Internal Tools / Enterprise Ops: Experience building internal tools, CRM systems, or high-density data applications focused on operational efficiency and scale. Regulated Environments: Background in highly regulated sectors (Fintech, Healthcare) dealing with strict role-based access control (RBAC) and data isolation. What We Offer Competitive salary Initial stock options grant Annual performance bonus Health, dental, and vision plans Work model: currently fully remote, with a future transition to a hybrid setup. Continuous learning opportunities Continuous learning opportunities Unlimited PTO Paid parental leave Empowering opportunities for growth in a dynamic entrepreneurial environment Equal Opportunity Employer At Félix, we are committed to providing equal employment opportunities to all qualified employees and applicants without regard to race, religion, nationality, sex, sexual orientation, gender identity, age, or disability. This policy applies to all terms and conditions of employment, including recruitment, hiring, placement, promotion, training, compensation, benefits, and termination. Want to learn more about our privacy practices? Check out our Privacy Policy .