The Cigna Group
Machine Learning Engineer - Express Scripts Canada (Mississauga)
Job Description
Machine Learning Engineer
Location: Mississauga, Canada.
Employment Type: Full-time.
Work Arrangement: Hybrid.
Department: Application Delivery Department.
Job Summary
Express Scripts Canada is looking for a Machine Learning Engineer to design, build, and operate data pipelines and ML services that detect unusual patterns in healthcare claims and pharmacy transactions. The role blends hands‑on data engineering (Oracle + ETL), model development (unsupervised learning), and API serving (Python/FastAPI), with close collaboration across business teams.
Key Responsibilities
- Design and implement ML data pipelines to ingest, engineer, and persist features from Oracle databases.
- Build and validate unsupervised ML models (MiniBatchKMeans/KMeans, DBSCAN) with dimensionality reduction and evaluation metrics.
- Serve models as REST APIs using FastAPI/Pydantic, including health endpoints, CORS, structured respo...