Senior Frontend/Ux Engineer - Ai-Driven Fintech, Remote

Humand Technologies, Inc.; Buenos Aires; Remote; ARS 85,158,000 - 191,605,000; Full time

Benefits offered by this job

Contractor payment in USD

100% remote work in international set­

Access to Argentine public holidays

Observability modernization project

Professional development and referrals

Job summary

Darwoft is seeking a Senior Frontend / UX Engineer to join a fast-growing U.S. fintech company building a Digital Wallet for cross-border payments.

This frontend-first role focuses on crafting intuitive, production-ready wallet features and leveraging AI tools to extend reach across the stack. You will translate UX/UI designs into scalable interfaces, collaborate with design and product teams, and own features end to end while delivering high-quality, accessible code in a fully remote,

Qualifications

• Strong hands-on experience with React, JavaScript, and TypeScript.
• Experience building fintech applications, digital wallets, or payment platforms.
• Solid understanding of UX principles, usability, interaction design, and user-centered development.
• A proven track record of building polished, production-ready user interfaces.
• Experience turning Figma designs into working applications.
• Practical experience with AI-assisted coding tools such as Cursor, Claude Code, GitHub Copilot, or similar.
• Ability to deliver complete features across frontend and backend boundaries.
• Experience with REST APIs, third-party integrations, and Backend for Frontend architectures.
• Strong understanding of frontend architecture, reusable components, and state management.
• Experience working in Agile product development environments.
• Strong communication, problem-solving, and independent execution skills.
• Comfort working hands-on with production code.

Responsibilities

• Design, develop, and maintain high-quality user interfaces for a Digital Wallet.
• Translate UX/UI designs and product requirements into functional, intuitive, responsive applications.
• Collaborate with product and design teams to improve user journeys, interactions, and usability.
• Own features end to end, from requirements through implementation and delivery.
• Use AI-powered tools to speed up frontend and full-stack development.
• Build and maintain Backend for Frontend (BFF) services supporting application requirements.
• Implement API integrations and backend functionality when needed.
• Ensure consistency, performance, accessibility, and maintainability across the app.
• Participate in code reviews and help improve development practices.
• Explore AI-assisted engineering to simplify workflows.

Skills

React

JavaScript

TypeScript

Fintech experience

Digital wallets

UI/UX

AI-assisted coding tools

REST APIs

BFF

Agile

Tools

Cursor

Claude Code

GitHub Copilot

Job description

Disclaimer – Must read: Commitment & Focus

This role requires full-time dedication, with clear priority given to Darwoft projects during the established working hours. It is not compatible with other full-time professional engagements. Any additional professional activities must be disclosed in advance and must not interfere with the responsibilities or working hours of this role.

About Darwoft

Darwoft is a software factory that builds custom software solutions and provides IT staff augmentation services for international clients, mainly in the United States and Latin America. We partner with startups and fast-growing companies to build high-impact digital products.

Our culture is people-first, focused on technical quality, long-term relationships, and collaboration. We combine technical excellence with a close, human approach to how we work.

Senior Frontend / UX Engineer – AI-Driven Full Stack | Contractor | LATAM

General Information

• Location: Remote – Latin America
• Contract Type: Independent Contractor (full-time)
• Industry / Project: Fintech – Digital Wallet for cross-border payments
• Time Zone: ART
• English Level: B2

About the Role

We are looking for a Senior Frontend / UX Engineer to join a fast-growing U.S. fintech company that is simplifying cross-border payments and international money transfers, with a strong focus on the Latino community in the United States. You will help build its Digital Wallet, the product through which users manage and move their money.

This is a frontend-first role. Your main job will be to build excellent user experiences: turning product requirements and UX/UI designs into intuitive, scalable, production-ready wallet features. You will also use AI-powered development tools to extend your reach across the stack, including Backend for Frontend (BFF) services, API integrations, and supporting backend functionality, so you can deliver complete features on your own when needed.

We are looking for someone who goes beyond implementing screens. You should understand how users interact with financial products, spot opportunities to improve the experience, and balance user experience, technical quality, and delivery speed. Your work will directly affect how easily and confidently users send money to their families and manage their finances.

Responsibilities

• Design, develop, and maintain high-quality user interfaces for a Digital Wallet.
• Translate UX/UI designs and product requirements into functional, intuitive, and responsive applications.
• Collaborate with product and design teams to improve user journeys, interactions, and overall usability.
• Own features end to end, from initial requirements through implementation and delivery.
• Use AI-powered development tools to speed up frontend and full-stack development.
• Build and maintain Backend for Frontend (BFF) services that support application requirements.
• Implement API integrations and supporting backend functionality when needed.
• Ensure consistency, performance, accessibility, and maintainability across the application.
• Take part in code reviews and help improve development practices.
• Find ways to simplify development workflows through AI-assisted engineering.

Requirements – Must-Have

• Strong hands-on experience with React, JavaScript, and TypeScript.
• Experience building fintech applications, digital wallets, or payment platforms.
• Solid understanding of UX principles, usability, interaction design, and user-centered development.
• A proven track record of building polished, production-ready user interfaces.
• Experience turning Figma designs or equivalent UX/UI specifications into working applications.
• Practical experience with AI-assisted coding tools such as Cursor, Claude Code, GitHub Copilot, or similar.
• Ability to deliver complete features across frontend and backend boundaries.
• Experience with REST APIs, third-party integrations, and Backend for Frontend (BFF) architectures.
• Strong understanding of frontend architecture, reusable components, and state management.
• Experience working in Agile product development environments.
• Strong communication, problem-solving, and independent execution skills.
• Comfort working hands-on with production code.

Nice-to-Have

• Experience with React Native and cross-platform mobile development.
• Familiarity with Node.js and modern backend frameworks.
• Experience building and maintaining design systems.
• Knowledge of authentication, authorization, and secure development for financial applications.
• Experience with AI-driven development workflows and agentic coding tools.
• Understanding of mobile-first design, accessibility, and frontend performance optimization.

What We Offer (Contractor)

• Contractor agreement with payment in USD.
• 100% remote work in an international setting.
• Access to Argentine public holidays.
• Direct involvement in modernizing core platform observability for a high-growth fintech ecosystem.
• Professional development, learning platforms, and referral programs.