Senior Full Stack Developer Needed for API Integration & Fixes (React, Node.js, Vector Database)

Posted 3 days ago

Worldwide

Summary

We are looking for a Senior Full Stack Developer to join our project and help resolve API-related issues in an existing application. The project is already developed and requires an experienced developer who can quickly understand the codebase, identify bottlenecks, troubleshoot API integrations, and implement robust solutions. We are specifically seeking someone with strong full-stack expertise who can work independently and deliver high-quality results. Responsibilities: Debug and fix existing API integration issues. Review and improve communication between frontend and backend services. Optimize API performance and reliability. Work with a vector database to ensure proper data indexing and retrieval. Implement error handling, logging, and testing where needed. Collaborate with our team to identify and resolve technical challenges. Requirements: 5+ years of Full Stack development experience. Strong experience with React.js, Node.js, and JavaScript/TypeScript. Proven experience with REST APIs and third-party integrations. Experience working with vector databases (Pinecone, Weaviate, Qdrant, Chroma, Milvus, etc.). Strong debugging and problem-solving skills. Ability to work independently and communicate clearly. Nice to Have: Experience with AI/LLM applications. Experience with RAG pipelines and embeddings. Experience with MongoDB or similar databases. When applying, please start your proposal with "API Expert" and include: Relevant API integration projects. Experience with vector databases. A brief description of a complex API issue you solved recently. We're looking for someone who can start immediately and help us get these integrations working smoothly.

  • $30.00

    Fixed-price
  • Expert
    Experience Level
  • Remote Job
  • One-time project
    Project Type

Contract-to-hire opportunity

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Skills and Expertise
Mandatory skills
JavaScript
Node.js
React
Activity on this job
  • Proposals:15 to 20
  • Last viewed by client:3 days ago
  • Interviewing:
    1
  • Invites sent:
    1
  • Unanswered invites:
    0
About the client
Member since Aug 23, 2025
  • United Kingdom
    Belfast6:30 PM
  • $7.8K total spent
    223 hires, 8 active
  • 235 hours

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