Senior Frontend Engineer: React/Next.Js, Ai‐Powered Ui
Webstacks
Consigue una respuesta de este empleador
Tu currículum y tu carta de presentación, adaptados exactamente a lo que buscan contratar.
Ventajas ofrecidas por este puesto de trabajo
Descripción de la vacante
Darwoft is seeking a Senior Frontend/UX Engineer to join a fast-growing U.S. fintech project from LATAM. You will build a Digital Wallet frontend, collaborating with design and product teams to deliver intuitive, scalable features.
The role emphasizes AI-assisted development, cross-functional collaboration, and ownership of features from design to production. You will work remotely in a distributed team, contributing to offline-first experiences and high-performance UI.
Formación
- Strong hands-on experience with React, JavaScript and TypeScript.
- Experience building fintech apps, digital wallets, or payments.
Responsabilidades
- Design, develop, and maintain high-quality user interfaces for a Digital Wallet.
- Translate UX/UI designs into functional, responsive applications.
- Collaborate with product and design teams to improve journeys and usability.
- Own features end-to-end from requirements to delivery.
- Use AI-powered tools to speed frontend and full-stack development.
- Build and maintain Backend for Frontend services.
Conocimientos
Herramientas
Descripción del empleo
At Tether, we’re not just building products, we’re pioneering a global financial revolution. Our cutting-edge solutions empower businesses—from exchanges and wallets to payment processors and ATMs—to seamlessly integrate reserve-backed tokens across blockchains. By harnessing the power of blockchain technology, Tether enables you to store, send, and receive digital tokens instantly, securely, and globally, all at a fraction of the cost. Transparency is the bedrock of everything we do, ensuring trust in every transaction.
Tether Finance: Our innovative product suite features the world’s most trusted stablecoin, USDT, relied upon by hundreds of millions worldwide, alongside pioneering digital asset tokenization services.
But that’s just the beginning:
Driving sustainable growth, our energy solutions optimize excess power for Bitcoin mining using eco-friendly practices in state‑of‑the‑art, geo‑diverse facilities.
Fueling breakthroughs in AI and peer‑to‑peer technology, we reduce infrastructure costs and enhance global communications with cutting‑edge solutions like KEET, our flagship app that redefines secure and private data sharing.
Democratizing access to top‑tier digital learning, we empower individuals to thrive in the digital and gig economies, driving global growth and opportunity.
At the intersection of technology and human potential, we are pushing the boundaries of what is possible, crafting a future where innovation and human capabilities merge in powerful, unprecedented ways.
Our team is a global talent powerhouse, working remotely from every corner of the world. If you’re passionate about making a mark in the fintech space, this is your opportunity to collaborate with some of the brightest minds, pushing boundaries and setting new standards. We’ve grown fast, stayed lean, and secured our place as a leader in the industry.
If you have excellent English communication skills and are ready to contribute to the most innovative platform on the planet, Tether is the place for you.
Our pioneering P2P development platform, built on our open‑source technology stack, Pear, eliminates the need for traditional server infrastructure. Pear platform facilitates direct deployment of applications from the developer’s machine to the user, enabling seamless scalability and performance. By leveraging Node.js‑based technology akin to BitTorrent, we create robust peer‑to‑peer connections and data replication systems that set the foundation for a decentralized web.
Learn more about Pear: docs.pears.com
Learn more about Keet: keet.io
In this role, you will be responsible for developing and maintaining Keet Desktop, our cross‑platform P2P communications application built with React and running on the Pear runtime. You’ll work on everything from UI/UX implementation to performance optimization, helping shape the future of decentralized communication.
Strong competency in state management (Redux, Redux Toolkit, Zustand, or similar).
Ability to write modular, maintainable, and well tested code.
Solid skillset in testing & debugging complex frontend applications.
Deep interest or experience with P2P technologies or distributed systems.
Comfort working in a remote, globally distributed team; good communication skills.
Experience with desktop application development (Electron, Tauri, or similar runtimes).
Familiarity with video/audio APIs (WebRTC, media streams) and real‑time communication.
Demonstrated ability to optimize UI performance: rendering, memory management.
Bonus: Past contributions to OSS projects, especially in P2P or decentralized tech.
Recruitment scams have become increasingly common. To protect yourself, please keep the following in mind when applying for roles:
Apply only through our official channels. We do not use third‑party platforms or agencies unless clearly stated. All open roles are listed on our official careers page.
Verify the recruiter’s identity. All our recruiters have verified LinkedIn profiles. If you’re unsure, you can confirm their identity by checking their profile or contacting us through our website.
Be cautious of unusual communication methods. We do not conduct interviews over WhatsApp, Telegram, or SMS. All communication is done through official company emails and platforms.
Double‑check email addresses. All communication from us will come from emails ending in @tether.to or @tether.io
We will never request payment or financial details. If someone asks for personal financial information or payment at any point during the hiring process, it is a scam. Please report it immediately.
When in doubt, feel free to reach out through our official website.
Our client is a remote product studio that builds MVPs and custom software for startups and companies past the idea stage. Clients pay for each build, and a small team works in two‑week sprints with AI coding tools used every day. Clients are startup founders and their teams, so developers explain tradeoffs to them directly.
They’ve been at it since 2020 and were profitable in 2025, with a 30% net margin. After building their own AI systems, they tripled monthly revenue with the same team size. Clients rate them 4.9 out of 5 in verified reviews, and the startups they build for have raised more than $25M in venture funding.
You’ll be the only mobile developer on a new offline‑first iOS and Android app, starting from the first project setup. The developer accounts, build pipeline and release tracks don’t exist yet, so that’s where you begin, and you stay on the same app through its public launch on the App Store and Google Play.
Sprints run two weeks with four to five features each, and coding agents write most of the first draft. You review every diff, add the tests the agents missed, and make the calls on sync, storage and releases. If you’d rather have a QA team or a release manager handle testing and store submissions, this probably isn’t the right seat.
You report to the studio’s leadership and work day to day with the lead developer and a backend developer, who’s your counterpart on the sync and upload APIs. You’ll also write risk notes and tradeoffs directly to the client team, with your recommendation attached. Success means sprints that close with their acceptance criteria verified, a write queue that neither loses nor doubles a submission on real devices, and an app live on both stores where sync failures show up in monitoring before anyone reports them.
Set up Apple and Google developer accounts, signing, CI builds and testing tracks
Build the local storage, write queue and retry logic that keep the app working offline
Agree the sync and upload APIs with the backend developer, and decide how conflicting edits resolve
Build phone‑number sign‑in with SMS codes, and push notifications that fall back to SMS
Build camera capture and e‑signature flows that save each signed record as a new version
Measure and improve startup time, memory and app size on low‑end Android phones
Handle store submissions, privacy disclosures and review rejections, and add crash and sync monitoring
4+ years building mobile applications, including React Native applications released on both the App Store and Google Play
Offline‑first work you built yourself: local storage, queued writes, retries and conflict handling
Performance tuning on low‑end Android, with startup time or memory measured before and after a change
Daily use of Cursor, Claude Code or a similar AI coding tool on production mobile work, with TypeScript, automated tests and CI around it
Clear written and spoken English for PR descriptions, risk notes and tradeoff explanations to a client team
Experience working from written acceptance criteria, and the judgment to push back on a merge that misses them
An in‑app e‑signature or document flow that stored versioned records
An application built for field, frontline or hourly workers
A localized application, or Spanish for testing the interface
Backend work such as writing an endpoint or a database migration
Crash reporting or sync monitoring you set up and then used to fix a problem seen in the field
Fully remote contractor role from LATAM, full time at about 40 hours a week
Core hours in US time zones, overlapping with the lead developer and the backend developer
One app to own, from the first project files through public release on both stores
Sync, storage and release decisions that are yours to make, with a backend developer as your counterpart
A team where AI coding agents are part of the daily workflow, with typed code, automated tests and CI in place
Intro Call: 30 minutes with atomic HR on your background and goals
Leadership Screening: A short call, possibly with an async part first
Product and Developer Conversation: How you take features to merge and agree sync APIs
Take‑Home Test: One feature like the real scope, built and checked
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 delivering custom software solutions and IT staff augmentation services to international clients, primarily in the United States and Latin America. We partner with startups and scale‑up companies to build high‑impact digital products, combining technical excellence with a people‑first culture built on long‑term relationships and collaborative work.
- Location: Anywhere in LATAM
- Work Model: 100% Remote
- Engagement: Full-time Contractor
- Project: FinTech · Customer Experience Operations Platform
- English Level: Advanced
- Seniority: Senior
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, availability, or working hours required for this role.
At Darwoft, we build digital products with heart.
We’re a Latin American technology company focused on creating impactful, human‑centered software in partnership with companies around the world. Our remote‑first culture is built on trust, continuous learning, collaboration, and strong engineering standards.
We’re passionate about technology, but even more about the people behind it. If you’re looking for an environment where your ideas matter, experimentation is encouraged, and your impact is tangible, welcome to Darwoft.
We’re 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.
- 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.
- 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.
- 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.
- 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.
Explore this and other opportunities at:
'/%3e%3cpath%20d='M101.744%2012.4726L102.894%2016.1947L99.0021%2013.2201L101.744%2012.4726ZM105.3%208.40937H100.488L99.0026%203.59473L97.5116%208.41047L92.7%208.40385L96.5965%2011.3834L95.1055%2016.1942L99.0021%2013.2196L101.408%2011.3834L105.3%208.40992V8.40937Z'%20fill='white'/%3e%3cdefs%3e%3clinearGradient%20id='paint0_linear_5593_1381'%20x1='90'%20y1='9.44471'%20x2='99'%20y2='9.44471'%20gradientUnits='userSpaceOnUse'%3e%3cstop%20stop-color='%2300AD70'/%3e%3cstop%20offset='0.998594'%20stop-color='%2300B67A'/%3e%3cstop%20offset='1'%20stop-color='%23DCDCE6'/%3e%3c/linearGradient%3e%3c/defs%3e%3c/svg%3e){kind=small}
