Full Stack Developer

Ultimate Asset; Madrid; Híbrido; EUR 50.000 - 70.000; Jornada completa

Descripción de la vacante

A leading tech recruitment agency is looking for a Senior Full Stack Engineer to join a fast-growing company in Madrid. The role requires 5-7 years of experience and expertise in full-stack web applications. Candidates must be fluent in English, and familiarity with Spanish/Catalan is a plus. Competitive salary and equity options are offered, along with flexible working arrangements.

Servicios

Competitive salary + equity/options

Flexible working arrangements

Formación

• 5 to 7+ years of hands-on software engineering experience.
• Strong experience building full-stack web applications.
• Deep knowledge of frontend frameworks and libraries.

Responsabilidades

• Design, implement, test, and maintain features end-to-end.
• Collaborate with Product, Design, QA, and other stakeholders.
• Write clean, modular, and well-tested code.

Conocimientos

Full-stack web applications

Frontend frameworks (React, Vue, Angular, Svelte)

Backend languages (Node.js, Python, Java, etc.)

Relational and NoSQL databases

Cloud infrastructure (AWS, GCP, Azure)

Containerization (Docker, Kubernetes)

Good communication skills

Fluent English

Descripción del empleo

Role

Senior Full Stack Engineer (5–7 yrs experience), Barcelona.

While we prefer candidates who are already based in Barcelona and are local, we will also consider EU citizens who are able to move to Barca. Some limited settling in assistance can be provided by the business. Our client is not able to offer Visas or sponsorship to Non-EU passport holders unfortunately.

About Us

Our client is a fast-growing scale-up in the Customer Sentiment analysis and insights platform that allows brands to decipher granular customer feedback and feelings towards brands and products and action those learnings with the view towards driving growth. My client has built a powerful platform used by many global B2C and B2C SaaS subscription businesses to get to the heart of user needs and so they can build better products in-line with user wishes.

Our client has a lean but mighty but world-class engineering and R&D team with high ownership, experimentation, and continuous learning. As we scale, we are seeking a strong Full Stack Engineer where there is future runway for personal growth and assuming more responsibility by becoming a team lead.

Role Summary

You will be a core member of the engineering team, contributing hands-on across the full stack (frontend, backend, APIs, databases, DevOps). We’re looking for a self-starter who has drive and initiative who can build features customers love but also collaborate with the squad based structure working with Product Designers and R&D people to drive better innovations that move the needle for the business.

Key Responsibilities

• Design, implement, test, and maintain features end-to-end, from UI / frontend to backend services and data layers
• Collaborate with Product, Design, QA, and other stakeholders to define requirements, ensure high quality, and deliver iteratively
• Write clean, modular, and well-tested code; perform code reviews and set standards / best practices
• Contribute to architectural decisions (scalability, performance, reliability, security)
• Monitor, debug, and optimize production systems; participate in incident response
• Mentor and coach junior / mid-level engineers; gradually take on technical leadership responsibilities
• Help set engineering processes (CI / CD, code reviews, documentation, testing, deployments)
• Aid in hiring, evaluating tools and libraries, tech stack evolution

Must-Have Qualifications

• 5 to 7+ years of hands-on software engineering experience
• Strong experience building full-stack web applications (frontend + backend)
• Deep knowledge of frontend frameworks / libraries (e.g. React, Vue, Angular, Svelte)
• Proficiency in one or more modern backend languages / frameworks (e.g. Node.js / Express, Python / Django / Flask / FastAPI, Java / Spring, Go, Ruby on Rails, etc.)
• Experience working with relational and NoSQL databases, APIs (REST, GraphQL)
• Familiarity with cloud infrastructure (AWS, GCP, Azure) and containerization (Docker, Kubernetes, etc.)
• Solid understanding of web fundamentals : HTTP, security, performance, caching, concurrency
• Experience writing tests (unit, integration), CI / CD pipelines, automated deployments
• Good communication skills, ability to work in a multilingual / remote-friendly environment
• Fluent English; Spanish / Catalan is a plus (but not mandatory)

Preferred / Differentiator Skills

• Experience in microservices architectures, event-driven systems, message queues
• Experience with DevOps / SRE practices (monitoring, logging, observability)
• Previous experience mentoring or leading engineers, or being tech lead
• Experience scaling systems to handle growth in users / traffic
• Familiarity with domain-specific tooling or domain (e.g. data pipelines, real-time systems, etc.)

What We Offer

Competitive salary + equity / stock options

The aim is to be five days in the office but there is flexibility when required to WFH for life needs