Senior Full-Stack Engineer (Python / TypeScript)

Title : Senior Full-Stack Engineer (Python / TypeScript) - W2 Contract Location : Sunnyvale, CA- Onsite Strong Python coding Rate - $50-$55/hour on W2 About The Role We're looking for a Full-Stack Engineer to design, build, and scale backend services and user-facing applications, including AI-powered workflows. You'll work across the stack, using Python and FastAPI on the server and TypeScript on the client, and you'll help bring LLM-based features into production. Key Responsibilities Design, develop, and maintain high-performance APIs and services using Python, FastAPI, and uvicorn.Build responsive, maintainable front-end and Node-based components in TypeScript.Model, optimize, and manage data in PostgreSQL, including schema design, indexing, query tuning, and migrations.Build agentic and LLM-driven workflows with LangGraph and LangChain.Write clean, well-tested, well-documented code, and take part in code reviews and design discussions.Work with product, design, and data teams to turn requirements into reliable, scalable solutions.Monitor, troubleshoot, and improve the performance, security, and reliability of production systems. Required Qualifications Strong professional experience with Python, including async programming.Hands-on experience building production APIs with FastAPI and running them on uvicorn.Proficiency in TypeScript and modern JavaScript tooling.Solid experience with PostgreSQL, including relational modeling and SQL performance tuning.Understanding of RESTful API design, authentication/authorization, and software engineering best practices.Experience with Git, CI/CD, and automated testing.Strong communication skills and the ability to work independently and collaboratively. Preferred Qualifications Experience with LangGraph and LangChain, such as building agents, tool-calling, RAG pipelines, and stateful multi-step workflows.Familiarity with LLM application patterns, including prompt design, evaluation, and observability.Experience with containerization (Docker) and orchestration (Kubernetes). Nice to Have Experience with AWS (for example EC2, ECS/EKS, Lambda, S3, RDS), ideally within Apple's environment.Experience with infrastructure-as-code and cloud-native deployment practices. Have a Great Day! Warm Regards, Sania Wadhwa Technical Recruiter Contact Details: 609-755-5388 Email: sania@applabsystems.com 4365 Route 1 South, Suite 105 Princeton, NJ 08540 www.applabsystems.com