Senior Full-Stack Engineer for Claude AI and API Integration Platform

Posted 17 hours ago

Worldwide

Summary

Summary We are seeking a senior full-stack engineer with at least 10 years of professional software development experience to help build and extend a modern web application that connects third-party systems with Claude AI. This role is primarily focused on software architecture, API development, cloud infrastructure, deployment automation, and reliable AI integration. The selected engineer will work across the frontend, backend, and DevOps layers of the platform. The project requires someone who can take ownership of technical decisions, review existing systems, build scalable integrations, and deliver production-ready features with limited supervision. Core Responsibilities * Build and maintain application features using Next.js and TypeScript * Develop backend services using Python and Django * Design secure REST APIs and internal service interfaces * Integrate external platforms, databases, authentication providers, and webhooks * Connect application workflows with the Anthropic Claude API * Create and optimize prompts for structured, predictable AI responses * Build AI agents that can access approved tools, services, and application data * Implement background jobs, queues, scheduled tasks, and asynchronous processing * Develop reusable integration modules for multiple external services * Configure AWS infrastructure for application services, storage, processing, and monitoring * Create and maintain CI/CD pipelines using GitHub Actions * Deploy frontend and backend services through Vercel, Render, AWS, or similar platforms * Improve system performance, security, scalability, and reliability * Add logging, monitoring, retry logic, exception handling, and operational alerts * Write technical documentation for architecture, integrations, and deployment processes Required Technical Experience * 10+ years of professional full-stack development experience * Advanced Next.js, React, and TypeScript experience * Strong Python and Django development experience * Strong knowledge of REST APIs, webhooks, OAuth, and third-party integrations * Production experience using AWS * Experience integrating Claude, OpenAI, or comparable large language models * Strong prompt-engineering skills * Experience building AI agents or tool-enabled AI applications * Experience with machine learning or applied AI systems * Strong Git and GitHub workflow experience * Experience creating CI/CD pipelines * Experience deploying applications through Vercel, Render, AWS, or similar hosting providers * Strong knowledge of PostgreSQL or similar relational databases * Understanding of application security, authentication, permissions, and data protection * Availability for at least four hours of overlap with U.S. Eastern Time during normal business hours Preferred Experience * Experience with the Anthropic Claude API * Experience with structured AI outputs and tool calling * Experience with Docker and containerized deployments * Experience with AWS Lambda, S3, RDS, ECS, SQS, CloudWatch, or related services * Experience with Redis, Celery, or other job-processing technologies * Familiarity with vector databases, embeddings, or retrieval-based AI applications * Experience building multi-tenant SaaS products * Experience maintaining production systems with active users Ideal Candidate The ideal candidate is comfortable working across multiple technical areas rather than focusing only on frontend or backend development. You should be able to: * Understand an existing codebase quickly * Recommend practical architectural improvements * Translate business requirements into technical solutions * Communicate risks and tradeoffs clearly * Deliver clean, maintainable, and well-tested code * Work independently while providing consistent progress updates * Collaborate with the team during overlapping U.S. Eastern Time working hours * Troubleshoot integration and deployment problems across the full technology stack Application Instructions Please include the following in your application: 1. A summary of your full-stack development experience 2. Examples of production applications you have built 3. Details about your Next.js, TypeScript, Python, Django, and AWS experience 4. Examples of complex API integrations you have completed 5. Examples of Claude AI, AI-agent, or prompt-engineering work 6. Links to relevant applications, case studies, GitHub repositories, or portfolio projects 7. Your current availability and typical working hours 8. The number of hours you can overlap with U.S. Eastern Time 9. Your hourly rate 10. Whether you are applying as an individual engineer or as part of a development team Please apply only if you have substantial senior-level experience, can demonstrate relevant production work, and can consistently provide the required Eastern Time overlap.

  • More than 30 hrs/week
    Hourly
  • 3-6 months
    Duration
  • Expert
    Experience Level
  • $15.00

    -

    $75.00

    Hourly
  • Remote Job
  • Ongoing project
    Project Type

Contract-to-hire opportunity

This lets talent know that this job could become full time.
Learn more
Skills and Expertise
Mandatory skills
Next.js
GitHub
AI Agent Development
Activity on this job
  • Proposals:50+
  • Interviewing:
    0
  • Invites sent:
    0
  • Unanswered invites:
    0
About the client
Member since Sep 26, 2025
  • USA
    Brooklyn6:07 PM
  • $2.8K total spent
    9 hires, 4 active
  • 129 hours

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