The Software Engineer (AI Backend Services) will design, develop, and own backend systems and components that power generative AI applications and large language model (LLM) integrations. This role focuses on independently architecting and delivering scalable, secure, and high-performance services using Python, FastAPI, and AWS cloud infrastructure, while mentoring junior engineers.

This is an individual contributor role

KEY RESPONSIBILITIES

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

Own end-to-end design and delivery of APIs and microservices for model serving, inference, and orchestration of AI agents

Architect and maintain AWS-based infrastructure for AI workloads (e.g., Lambda, EKS) with focus on scalability and reliability

Make independent technical decisions for component-level architecture and design patterns

Lead integration efforts for LLMs and generative AI models into production systems using LangChain, Langfuse, and litellm

Establish monitoring, logging, and observability best practices for AI backend services

Optimize backend performance for large-scale AI applications

Mentor Software Engineer II team members through code reviews and technical guidance

Collaborate with cross-functional teams and influence technical direction across multiple projects

BASIC QUALIFICATIONS

4-7 years of professional software engineering experience with strong backend focus

Expert-level proficiency in Python for backend development in production environments

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

Proven experience designing and building scalable systems on AWS (Lambda, API Gateway, EKS)

Deep knowledge of microservices architecture, API design, and distributed systems

Strong experience with containerization (Docker/Kubernetes) and orchestration

Demonstrated ability to own technical components and make independent architectural decisions

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

PREFERRED QUALIFICATIONS

Extensive experience building and scaling APIs and backend systems for AI/ML workloads in production

Deep expertise with FastAPI and asynchronous Python programming

Experience architecting event-driven systems for AI applications

Track record of mentoring engineers and conducting effective code reviews

Strong understanding of system design patterns and trade-offs

Experience with infrastructure-as-code (Terraform, CloudFormation)

Knowledge of model deployment strategies and MLOps practices

Proven ability to drive technical initiatives and influence engineering culture

Excellent communication skills and experience working across teams

Work assignment location : Remote

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