Senior Fullstack Software Engineer (100% Remote)

Tether EV; A distancia; EUR 60.000 - 80.000; Jornada completa

Descripción de la vacante

A leading fintech company in Barcelona is seeking a Senior Fullstack Software Engineer to build and scale GPU-accelerated cloud services. The role involves working on backend infrastructures and creating user-friendly interfaces for developers. Candidates should have over 5 years of experience with strong skills in Node.js, JavaScript, and React, and familiarity with distributed systems and containerization technologies. Join a passionate team driving innovation in financial technology while working remotely.

Servicios

Flexible working hours

Remote work opportunities

Collaborative team environment

Formación

• 5+ years of experience in fullstack development with strong emphasis on backend systems.
• Expert in Node.js/JavaScript for backend development and React frontend framework.
• Experience with containerization technologies and orchestration platforms.

Responsabilidades

• Design and implement robust backend services and APIs for AI model inference.
• Build responsive web interfaces for training job management and real-time dashboards.
• Contribute to the design of distributed systems using peer-to-peer technologies.

Conocimientos

Node.js

JavaScript

React

Distributed systems

API design

Docker

Kubernetes

Data modeling

Herramientas

Docker

Kubernetes

Redis

Kafka

Descripción del empleo

Join Tether and Shape the Future of Digital Finance. 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 Power fuels sustainable growth by optimizing excess power for Bitcoin mining using eco‑friendly practices in our state‑of‑the‑art, geo‑diverse facilities. With Tether Data, we fuel breakthroughs in AI and peer‑to‑peer technology, reducing infrastructure costs and enhancing global communications. Tether Education democratizes access to top‑tier digital learning, empowering individuals to thrive in the digital and gig economies. At the intersection of technology and human potential, we push the boundaries of what is possible, crafting a future where innovation and human capabilities merge in unprecedented ways.

Why Join Us? 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. Are you ready to be part of the future?

About the Job

As a Senior Fullstack Software Engineer on the CosmicAC team, you will play a critical role in building and scaling our GPU‑accelerated cloud services platform. You’ll work on both the backend infrastructure that powers AI/ML workloads at scale and the frontend interfaces that make these capabilities accessible to developers and data scientists. This position requires deep technical expertise in distributed systems, strong backend development skills, and the ability to create intuitive user experiences.

You’ll be joining a team that’s pushing the boundaries of decentralized AI infrastructure, working on everything from Kubernetes orchestration and managed inference services to API design and real‑time monitoring dashboards. Your work will directly impact how developers interact with and deploy AI models in production environments.

Responsibilities

• Design and implement robust backend services and APIs that handle AI model inference, resource orchestration, and workload distribution across distributed GPU infrastructure.
• Build responsive and intuitive web interfaces for training job management, model deployment workflows, and real‑time monitoring dashboards using modern JavaScript frameworks.
• Contribute to the design and implementation of distributed systems using peer‑to‑peer technologies (Holepunch stack).
• Develop and maintain APIs that support both synchronous and asynchronous inference patterns, ensuring compatibility with industry standards.
• Implement monitoring, logging, and telemetry solutions to ensure high availability and performance of the platform services.
• Work closely with DevOps, AI/ML engineers, and product teams to deliver integrated solutions that meet technical and business requirements.Maintain high standards for code quality through peer reviews, testing, and documentation while championing security best practices.

Qualifications

• 5+ years of experience in fullstack development with strong emphasis on backend systems.
• Expert‑level proficiency in Node.js/JavaScript for backend development and React frontend framework.
• Proven experience building and scaling distributed systems or event‑driven architectures.
• Strong understanding of API design and implementation, including authentication, rate limiting, and versioning.
• Experience with containerization technologies (Docker) and orchestration platforms (Kubernetes).
• Proficiency with databases, and a deep understanding of data modeling and optimization.
• Solid understanding of networking, security principles, and best practices for production systems.
• Experience with real‑time data streaming and RPC implementations.
• Ability to work independently in a remote environment and communicate effectively across time zones.

Preferred

• Experience with peer‑to‑peer technologies (Hyperswarm, libp2p, WebRTC) or similar distributed communication protocols.
• Familiarity with AI/ML inference APIs and OpenAI‑compatible endpoints.
• Previous experience building AI SaaS or PaaS platforms.
• Knowledge of GPU resource management and ML framework infrastructure.
• Experience with message queuing systems (Redis, RabbitMQ, Kafka).
• Familiarity with observability tools (Prometheus, Grafana, ELK stack).
• Understanding of WebAssembly or edge computing paradigms.Contributions to open‑source projects in relevant domains.

Important Information for Candidates

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 for recruitment 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 ******@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.