Software Engineer

Software Engineer (AI Backend Services) - Evergreen Role

Pfizer is seeking a skilled Software Engineer specializing in AI Backend Services to join our innovative team. This evergreen role involves the end-to-end design, development, and ownership of robust backend systems and components essential for powering cutting-edge generative AI applications and large language model (LLM) integrations. The ideal candidate will independently architect and deliver scalable, secure, and high-performance services utilizing Python, FastAPI, and AWS cloud infrastructure, while also contributing to the growth of junior engineers.

This is an individual contributor position based remotely.

Key Responsibilities

• Design and implement Python-based backend services on FastAPI for AI workloads, including LLM integration and generative AI pipelines.
• Own the 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 a focus on scalability and reliability.
• Make independent technical decisions regarding component-level architecture and design patterns.
• Lead integration efforts for LLMs and generative AI models into production systems using LangChain, Langfuse, and litellm.
• Establish best practices for monitoring, logging, and observability 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 a 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 a 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.

Location

Chennai, Tamil Nadu (Remote work assignment)

Company Information

Pfizer is an equal opportunity employer and complies with all applicable equal employment opportunity legislation in each jurisdiction in which it operates. Department: Information & Business Tech.