Full Stack Engineer

Senior Full Stack Software Engineer (Python, React), Remote, Madrid/Barcelona Help build high-performance web applications used by thousands of users.

We’re looking for a

Senior Full Stack Software Engineer

with a strong

backend focus in Python

and solid

React experience

to help design and scale modern web applications. This role is ideal for someone who enjoys solving complex engineering challenges, making architectural decisions, and building systems designed for reliability and performance at scale. You’ll work closely with engineers and stakeholders to deliver robust, user-friendly applications while contributing to both backend architecture and modern frontend improvements.

About the Role As a

Senior Full Stack Engineer , you will play a key role in shaping the technical direction of the platform. You’ll lead backend architecture decisions, build scalable services, and help evolve the frontend experience using modern technologies. The platform supports

thousands of concurrent users and high-frequency external integrations , so performance, stability, and scalability are critical. You’ll also help drive engineering best practices, improve testing coverage, and contribute to continuous technical improvements across the stack.

What You’ll Be Doing Leading the

design and development of backend services

using Python Building scalable APIs and services capable of supporting

high traffic and concurrent users Contributing to

modern frontend development

using React and TypeScript Making

key architectural and technical decisions Improving

system performance, reliability, and scalability Writing

well-tested backend and frontend code Implementing

end-to-end and integration testing using Playwright Collaborating with engineers and stakeholders to deliver high-quality solutions Supporting ongoing

technology improvements and engineering best practices

What We’re Looking For Solid professional background developing

backend services with Python Several years of experience working with

JavaScript for web applications , ideally using

React Proven track record building

scalable web platforms and API-driven applications Experience designing systems that prioritise

stability, efficiency, and high performance Strong understanding of

modern backend design patterns and scalable architectures Hands-on experience implementing

automated testing and maintaining reliable codebases Confidence in

contributing to architectural discussions and influencing technical direction Experience with technologies such as: Python, FastAPI, ReactJS, TypeScript, Tailwind, Vite Redis, MongoDB, PostgreSQL, Alembic Docker, Kubernetes, Azure DevOps, AWS Experience with infrastructure or DevOps practices is

a plus , but not mandatory as deployments and operations are handled by a dedicated infrastructure team.

Additional Details Location:

Remote, candidates must be based in

Madrid or Barcelona Contract type:

6-month B2B contract, with possibility to extend Experience level:

Senior Software Engineer Language:

Professional

English proficiency required We’re looking for engineers who bring a

strong backend mindset, solid testing practices, and a proactive attitude toward continuous improvement .

Interested? If you’re excited about building scalable systems, solving challenging engineering problems, and working with modern technologies, we’d love to hear from you. Apply via LinkedIn or reach out directly to discuss the opportunity.