Senior Full-Stack Developer - PT Freelance - Worldwide

Role Overview

We are seeking a skilled Senior Full-Stack Developer to collaborate closely on an ongoing basis. The ideal candidate will possess strong technical expertise and excellent communication skills, providing frequent updates and ensuring efficient project progression.

Responsibilities

• Collaborate closely to address bugs quickly and implement improvements efficiently.
• Develop and maintain backend systems using Python, focusing on production APIs and services with frameworks such as FastAPI or Django.
• Build modern full-stack applications using React/Next.js (or Vue) for frontend development, integrated with backend APIs.
• Design and optimize SQL and Postgres databases, including schema design, migrations, indexing, and performance tuning.
• Implement containerization using Docker and manage deployments on AWS services like ECR, S3, and AWS App Runner.
• Develop robust data ingestion pipelines for both bulk and incremental data loads, ensuring efficient tracking and audit capabilities.
• Package and serve machine learning models in production, ensuring proper feature preparation, artifact loading, and versioning.
• Apply a strong system design mindset to separate concerns across API, inference, and scheduled ingest services, maintaining observability through logs and metrics.

Required Skills

• Excellent English communication skills, both written and spoken.
• Proven full-stack development experience.
• Proficiency in Python backend development, including FastAPI, Django, or similar frameworks.
• Expertise in modern frontend frameworks such as React/Next.js or Vue.
• Strong knowledge of SQL and Postgres, including schema design and performance optimization.
• Experience with containerization and AWS deployment services.
• Familiarity with data ingestion techniques and ML model serving in production environments.
• Understanding of ML metrics such as ROC-AUC, PR-AUC, F1, and precision/recall.

Nice to Have

• Experience with FastAPI async patterns and maintaining OpenAPI standards.
• Background in ETL/ELT processes or working with large public datasets, particularly in healthcare or biomedical fields.
• Familiarity with CI/CD practices, such as GitHub Actions, and basic MLOps principles.