Senior Python Engineer - FastAPI, AI/ML & Cloud - Salt Search : Job Details

Location: Hybrid - London Office

Day Rate: £400-£600 (Outside IR35, Negotiable)

Contract Length: 6 months (with possible extension)

Industry: Government-funded Non-Profit

Salt Recruitment is hiring an experienced Senior Python Engineer on behalf of a government-funded non-profit organisation working on an AI-driven platform. This is a hands-on development role focused on FastAPI microservices, AI/ML integrations, and cloud deployment.

We are looking for a strong back-end engineer with a proven track record in building scalable microservices, working with AI/NLP models, and deploying applications in a cloud-based environment (AWS/GCP).

• Develop, maintain, and optimise Python microservices using FastAPI.
• Integrate AI/ML models and NLP technologies into backend services.
• Build and optimise data pipelines for machine learning applications.
• Deploy and manage services in AWS/GCP, using Docker, Kubernetes, and Terraform.
• Ensure best practices in testing (Pytest), CI/CD (GitHub Actions), and observability (OpenTelemetry).
• Work closely with data scientists, DevOps engineers, and product managers in an Agile team.

• Proven experience in a similar Senior Python Engineer role.
• Strong proficiency in Python, including both object-oriented and functional programming.
• Expertise in FastAPI and its ecosystem (Pydantic, SQLAlchemy, Alembic).
• Experience with microservices architecture and serverless/lambda functions.
• Strong database skills, particularly PostgreSQL.
• Familiarity with common Python libraries (Pandas, NumPy, Jupyter Notebooks).
• Experience with Git, GitHub, Docker, and cloud deployments.
• Understanding of monitoring and observability using OpenTelemetry.

• Cloud expertise in AWS (certifications preferred).
• Infrastructure as Code (Terraform, Kubernetes).
• Hands-on experience with AI/ML frameworks (Scikit-Learn, TensorFlow, Hugging Face, PyTorch).
• Familiarity with ML/Gen AI tools (LangChain, MLFlow, SageMaker, Bedrock, Weights & Biases).
• Experience with OAuth, JWT authentication mechanisms.

• Work on a cutting-edge AI/ML project with real-world impact.
• Flexible hybrid working with a London-based office.
• Outside IR35 contract with a competitive day rate (£400-£600).
• Exposure to modern cloud and AI technologies.

Applicants are also welcome to apply directly by emailing their CV to .

*Rates depend on experience and client requirements