Senior Software Engineer

Merlin Digital Partner; Madrid; Presencial; EUR 60.000 - 90.000; Jornada completa

Ventajas ofrecidas por este puesto de trabajo

Competitive compensation

Technical leadership opportunities

Autonomy and ownership

International growth

Descripción de la vacante

Merlin Digital Partner in Madrid, Spain, is seeking a Senior Software Engineer (Python) to design and build backend systems powering connected health products. You will own architecture and production deployments, collaborating with Product, AI, Embedded and Frontend teams to deliver scalable APIs and data models.

Requirements include 5+ years in backend, Python expertise with FastAPI or Django, REST APIs, PostgreSQL, Docker and CI/CD.

Formación

• 5+ years of backend software engineering experience.
• Strong Python development experience with FastAPI or Django.
• Experience designing scalable REST APIs and PostgreSQL data models.
• Experience with cloud platforms (GCP or similar) and Docker.
• Professional English level; able to collaborate with international teams.
• Availability to work on-site 3–4 days per week.

Responsabilidades

• Design and develop scalable backend services in Python.
• Build and evolve REST APIs powering web, mobile, and IoT apps.
• Develop cloud-native services focusing on reliability and performance.
• Contribute to cloud infrastructure, CI/CD, and monitoring.
• Mentor engineers and participate in architectural decisions.
• Improve observability, security, and code quality.

Conocimientos

Python

REST APIs

PostgreSQL

SQL

Docker

Git

CI/CD

FastAPI

Django

GCP

Hetzner

Firebase

Sentry

Celery

Testing

English

Architecture

Herramientas

Docker

Git

CI/CD pipelines

Sentry

Celery

Descripción del empleo

We are Merlin Digital Partner! A leading IT and Digital headhunting company who stands out from the crowd, boasting over a decade of experience. Weve successfully collaborated and played a pivotal role in the growth of industry heavyweights such as Wallapop, Glovo, Banc Sabadell, and Duracell, among others. Our emphasis lies in people-centric approaches and optimizing the selection processes. Our mission is to revolutionize companies by seamlessly integrating top-tier talent. What sets us apart is our in-depth understanding of each partner (being their best influencer!), addressing not only their needs but also capturing their essence. Our partner is a fast-growing HealthTech company developing connected technologies at the intersection of hardware, embedded systems, IoT, AI and digital health. Their technology transforms everyday environments into intelligent health platforms, enabling seamless and continuous health monitoring. We are currently looking for a Senior Software Engineer (Python) to join their Engineering team and help build the embedded technologies powering the next generation of connected health products. Mission: As a Senior Software Engineer, your mission will be to design and develop the backend systems, cloud infrastructure and APIs powering the companys connected technologies. You will have a key role in building scalable, reliable and secure software that connects devices, AI-driven services and customer-facing applications. Working closely with Product, AI, Embedded and Frontend teams, you will take ownership of solutions from architecture and implementation through deployment and production, helping define the technical foundations of the platform as the company scales.

The Role:

• Designing, developing and maintaining scalable backend services, primarily using Python.
• Building and evolving REST APIs powering web, mobile and IoT applications.
• Designing and optimizing databases, data models and system integrations.
• Developing cloud-native services with a strong focus on reliability, performance and scalability.
• Contributing to cloud infrastructure, deployment pipelines and system monitoring.
• Improving platform performance, observability and security.
• Troubleshooting production issues and continuously improving system reliability.
• Collaborating closely with Product, AI, Embedded and Frontend teams to design and deliver new product capabilities.
• Participating in software architecture and technical design decisions.
• Building clean, maintainable and well-tested software following strong engineering practices.
• Improving development workflows, CI/CD pipelines and code quality.
• Providing technical guidance and mentoring other engineers through code reviews and knowledge sharing.Continuously evaluating new technologies, tools and engineering best practices.

What we need:

• 5+ years of professional backend software engineering experience. More extensive senior-level experience will be highly valued.
• Strong professional development experience with Python.
• Experience working with modern Python backend frameworks such as FastAPI, Django or similar.
• Solid experience designing, developing and maintaining REST APIs.
• Experience designing scalable software architectures and contributing to architectural decisions.
• Strong knowledge of SQL and PostgreSQL, including database and data model design.
• Experience working with Firebase.
• Experience deploying and operating applications on cloud platforms such as GCP, Hetzner or similar.
• Hands-on experience with Docker, Git and CI/CD pipelines.
• Experience with monitoring, observability and background processing tools, such as Sentry, Celery or similar.
• Strong understanding of software engineering best practices, including testing, maintainability, code reviews and clean software design.
• Excellent debugging, analytical and problem-solving skills.
• Ability to take ownership of technical solutions from design and architecture through deployment and production.
• Professional English level.
• Disponibilidad para acudir a oficinas 4-3 días a la semana.

Nice to Have

• Experience with event-driven architectures and technologies such as Kafka, RabbitMQ or MQTT.
• Experience with Infrastructure as Code (IaC).
• Previous experience working with IoT or connected devices.
• Experience integrating AI or Machine Learning services into production systems.
• Experience building or operating distributed systems.
• Previous experience in startups, scale-ups or fast-growing technology companies.
• A product-oriented mindset and the ability to comfortably collaborate across different engineering disciplines.

What we offer:

• Join a fast-growing HealthTech company building a new generation of intelligent, connected health technologies.
• Work at the intersection of embedded systems, hardware, IoT, cloud, AI and digital health.
• Build technologies powering products already used by leading sports organizations and enterprise customers worldwide.
• Take ownership of high-impact projects, from embedded software development through system integration and production.
• Collaborate with a talented multidisciplinary team across Hardware, Backend, AI, Data and Product.
• Have a visible impact on technical and architectural decisions as the platform and engineering organization continue to evolve.
• Work in a fast-paced environment with a high level of autonomy and ownership.
• Strong opportunities for professional growth and technical leadership as the company scales internationally.
• Competitive compensation based on experience.

Senior Software Engineer • Madrid, Spain