Senior / Staff Full Stack & AI Engineer

Company: NPB Labs S.L.

Location: Barcelona, Spain / 100% Remote

Type: Full-time contractor

Language: Professional English

About the RoleNPB Labs S.L. is looking for a highly experienced Senior / Staff Full Stack & AI Engineer to join the team building a modern cloud-native platform for complex healthcare, laboratory, operational, and patient-facing workflows.

This is a hands-on role with strong ownership across frontend, backend, AWS, AI/LLM services, integrations, architecture, and CI/CD.

What You Will Do

- Build and maintain scalable applications using React and TypeScript.
- Design backend services, APIs, integrations, and distributed workflows.
- Develop cloud-native solutions on AWS.
- Integrate LLMs and Generative AI into production applications.
- Build solutions using Amazon Bedrock, RAG, embeddings, agents, and Knowledge Bases.
- Perform Prompt Engineering, prompt optimization, structured outputs, guardrails, and LLM evaluation.
- Work with asynchronous architectures, queues, events, and background processing.
- Design and optimize relational databases and APIs.
- Maintain CI/CD pipelines using GitHub Actions.
- Participate in architecture, code reviews, security, observability, and production troubleshooting.
- Mentor engineers and contribute to technical standards.

Core Stack

- React
- TypeScript
- Node.js and/or Python
- REST APIs
- PostgreSQL / MySQL / SQL
- AWS
- Amazon Bedrock
- RAG
- LLMs / Generative AI
- Prompt Engineering
- GitHub
- GitHub Actions
- Docker
- Terraform
- Event-driven architectures





Relevant AWS services may include:
- Lambda
- ECS / EKS
- EC2
- RDS
- S3
- API Gateway
- SQS
- SNS
- EventBridge
- CloudWatch
- IAM
- Secrets Manager
- Bedrock

Required Experience

- 8+ years of professional software engineering experience.
- Strong Full Stack development experience.
- Advanced experience with React and TypeScript.
- Strong backend and API development skills.
- Production experience with AWS.
- Experience with AI/LLM-based applications.
- Understanding of RAG, Prompt Engineering, agents, embeddings, and LLM integration patterns.
- Strong experience with Git, GitHub, CI/CD, and GitHub Actions.
- Experience with relational databases, Docker, testing, and distributed systems.
- Strong software architecture and problem-solving skills.
- Ability to work independently and own complex technical initiatives.

Nice to Have

- Amazon Bedrock Knowledge Bases, Agents, and Guardrails
- LangChain / LangGraph / LlamaIndex
- Vector databases
- Kubernetes
- Terraform
- OCR / document processing
- HL7, FHIR, ASTM
- LIS / HIS / healthcare platforms
- High-volume or regulated systems

EnglishProfessional working proficiency in English is required. Candidates must be comfortable participating in technical meetings, discussing architecture, writing documentation, and collaborating with international teams.

Working Model

- 100% Remote
- Full-time
- Company based in Barcelona
- International environment
- High autonomy and ownership
- Strong focus on cloud, AI, automation, and scalable software architecture

📌 SR. Full Stack Engineer (España)
🏢 NPB Labs
📍 España