Senior Full Stack Engineer

Posted yesterday

Worldwide

Summary

Senior Full Stack Engineer Employment Type: Full-Time (40 hours/week) Work Setup: Remote Shift: 1:00 AM to 9:00 AM CST About Performance AI Performance AI builds production-grade AI systems that help organizations automate workflows, improve decision-making, and accelerate growth. We partner with healthcare organizations, financial institutions, enterprise businesses, and high-growth companies to solve complex operational challenges through scalable software and intelligent automation. Our engineering team owns solutions from architecture through deployment, building reliable systems that integrate with real business operations and deliver measurable outcomes. About the Role We are seeking a Senior Full-Stack AI Platform Engineer to build modern web applications, scalable backend services, AI-powered workflows, and enterprise integrations. We are looking for engineers who combine strong software engineering fundamentals with hands-on experience building production systems. The ideal candidate understands the underlying technologies behind modern frameworks, can clearly explain architectural decisions and technical trade-offs, and takes ownership of building reliable, maintainable, and scalable software. You will work closely with engineering leadership to solve complex technical challenges, contribute to architectural decisions, and build software that is secure, maintainable, and scalable. What You'll Build AI-powered enterprise applications Modern React and Next.js web applications Scalable backend services using Node.js and TypeScript Secure authentication and payment systems Enterprise integrations with third-party platforms Event-driven and real-time applications Internal AI automation platforms Responsibilities Backend Engineering Design and maintain backend services using Node.js, Express, and TypeScript. Build secure REST APIs and GraphQL services. Implement authentication, authorization, logging, monitoring, caching, and background processing. Optimize application performance and troubleshoot complex production issues. Frontend Engineering Build responsive applications using React, Next.js, and TypeScript. Develop reusable and maintainable UI components. Optimize rendering performance and user experience. Manage client-side and server-side state effectively. AI Engineering Design and deploy AI-powered applications using modern LLMs. Build Retrieval-Augmented Generation (RAG) solutions. Work with embeddings, vector databases, and agentic workflows using frameworks such as LangChain or LangGraph. Optimize retrieval quality, latency, and inference cost. Systems & Integrations Design and build secure integrations with enterprise platforms through REST APIs, webhooks, and event-driven architectures. Develop scalable database solutions using MongoDB and SQL. Build asynchronous workflows using queues and background workers. Engineering Excellence Participate in architecture and technical design discussions. Write clean, maintainable, and well-tested code. Review code and contribute to engineering standards. Mentor teammates through technical collaboration. Required Qualifications 3 to 5+ years of professional software engineering experience. Strong experience building backend services using Node.js, Express, and TypeScript. Advanced experience with React and Next.js. Experience designing maintainable software architectures. Experience building secure REST APIs. Experience with MongoDB and relational databases. Experience integrating third-party APIs. Experience with Git and collaborative development workflows. Excellent written and verbal English communication skills. Ability to work independently in a fast-paced remote environment. Core Engineering Competencies Successful candidates should demonstrate experience with: Asynchronous programming and the Node.js event loop. Software architecture and distributed systems. Authentication and authorization using JWT and OAuth. API security and secure software design. Caching strategies using Redis or similar technologies. Background jobs, queues, and asynchronous processing. Database design and performance optimization. Production debugging and troubleshooting. Designing maintainable systems that scale over time. AI Experience Experience building AI-powered software using one or more of the following is preferred: LangChain LangGraph Retrieval-Augmented Generation (RAG) Vector databases Embeddings OpenAI, Claude, Gemini, or similar LLM APIs Preferred Qualifications Experience with any of the following is a plus: Stripe payment integrations GraphQL Docker Redis RabbitMQ, Kafka, or BullMQ Kubernetes AWS, Azure, or Google Cloud Platform CI/CD pipelines HL7 and FHIR healthcare integrations SOC 2, HIPAA, or GDPR environments What Success Looks Like Successful engineers on our team: Take ownership of solutions from design through deployment. Understand the engineering principles behind the technologies they use. Can confidently explain architectural decisions and technical trade-offs. Build secure, maintainable, and scalable software. Communicate technical concepts clearly and collaborate effectively across the engineering team. Continuously improve code quality, system reliability, and engineering best practices. Interview Process Our interview process focuses on engineering fundamentals, system design, and real-world problem solving. Candidates should expect discussions around: Systems they have personally built. Architecture and technical decision-making. Scalability and performance optimization. Authentication and security. AI application architecture. Software engineering fundamentals. Individual ownership and technical contributions. Candidates should be prepared to explain the engineering concepts behind the technologies listed on their résumé and discuss the reasoning behind the architectural decisions they made. Why Join Performance AI Build meaningful AI products used in production. Work directly with experienced engineering leadership. Own technical decisions with real business impact. Solve challenging engineering problems across multiple industries. Join a collaborative team that values curiosity, craftsmanship, and continuous learning.

  • More than 30 hrs/week
    Hourly
  • 6+ months
    Duration
  • Intermediate
    Experience Level
  • $10.00

    -

    $16.00

    Hourly
  • Remote Job
  • Ongoing project
    Project Type

Contract-to-hire opportunity

This lets talent know that this job could become full time.
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Skills and Expertise
Mandatory skills
LangChain
Docker
Kubernetes
Activity on this job
  • Proposals:50+
  • Last viewed by client:1 hour ago
  • Interviewing:
    20
  • Invites sent:
    0
  • Unanswered invites:
    0
About the client
Member since Oct 25, 2021
  • United States
    Chicago4:02 PM
  • $272K total spent
    87 hires, 12 active
  • 21,448 hours

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