The AI Backend Python Engineer (SE II) will develop and maintain backend systems that power generative AI applications and large language model (LLM) integrations. This role focuses on implementing features for scalable, secure, and high-performance services using Python and AWS cloud infrastructure, with guidance from senior engineers.

This is an individual contributor role.

KEY RESPONSIBILITIES

Implement Python-based backend services (on FastAPI) for AI workloads, including LLM integration and generative AI pipelines

Develop APIs and microservices for model serving and inference with guidance from senior team members

Build and maintain AWS-based infrastructure components for AI workloads (e.g., Lambda, EKS)

Write clean, well-tested, and maintainable code following established patterns and best practices

Integrate LLMs and generative AI models into production systems using frameworks like LangChain, Langfuse, and litellm

Implement monitoring, logging, and observability features for assigned backend services

Participate in code reviews and contribute to team knowledge sharing

Debug and resolve production issues with support from senior engineers

Collaborate with cross-functional teams to understand requirements and deliver features

BASIC QUALIFICATIONS

2-4 years of professional software engineering experience or equivalent

Strong proficiency in Python for backend development in production environments

Understanding of LLMs, generative AI concepts, and modern AI frameworks (e.g., litellm, LangChain)

Experience with AWS services (Lambda, API Gateway, EKS)

Knowledge of RESTful API design and microservices architecture

Familiarity with containerization (Docker) and version control (Git)

Bachelor's degree in Computer Science, Engineering, or related field, or equivalent practical experience

Strong problem-solving skills and attention to detail

PREFERRED QUALIFICATIONS

Hands-on experience building APIs for AI/ML workloads in production

Experience with FastAPI or similar Python web frameworks

Familiarity with Langfuse for LLM observability

Knowledge of CI/CD practices and automated testing

Understanding of database systems (SQL and NoSQL)

Experience with event-driven architectures

Strong communication skills and ability to work collaboratively in a team environment

Work location assignment : Remote

Pfizer is an equal opportunity employer and complies with all applicable equal employment opportunity legislation in each jurisdiction in which it operates.