Chrome Extension Developer. Gmail API + React + AI Sidebar

Posted 4 weeks ago

Worldwide

Summary

I'm building a Chrome extension called that helps people stay on top of their professional relationships. Think of it as a daily prioritized queue of people to follow up with — powered by email data and AI. I've already built a fully functional React UI prototype (1300+ lines of JSX) with mock data. I need a developer to connect it to real data sources and make it production-ready. What the extension does: - Lives as a sidebar overlay in the browser (similar to Superhuman Go or Grammarly) - Connects to Gmail via OAuth, scans sent/received emails, and builds a contact graph - Calculates relationship health based on email frequency, recency, and cadence patterns - Uses Claude API to generate personalized follow-up drafts based on email thread history - Enriches contacts with company signals (via domain/news lookup) and location data - Sends emails directly via Gmail API with the user's signature - Includes a floating chat interface for asking questions about contacts What's already built: - Complete React sidebar UI with all views (brief queue, active card, onboarding, playbook settings) - Contact cards with draft editing, notes, signal sections, send/skip/snooze/pin actions - Floating chat with context-aware responses and slash commands - All interaction patterns, animations, and state management working with mock data What I need you to build: Phase 1 (Week 1-2): - Chrome extension scaffolding (Manifest v3, content script injection, sidebar iframe) - Gmail OAuth via Chrome identity API - Gmail API integration: scan 12 months of sent/received, extract contacts, calculate cadence - Connect real contact data to existing React UI - Local persistence via Chrome storage Phase 2 (Week 3-4): - Claude API integration for draft generation using real email thread history - Company signal enrichment from domain-based news search - Location/weather lookup from company data - Gmail API send with user's signature + undo functionality - LinkedIn profile search/matching (show top 3 candidates, user confirms) About me: I'm a technical founder who designed the entire product and built the UI prototype myself. I have strong opinions about UX and product decisions. You'll be executing on a clear vision, not figuring out what to build. I'm available for daily async check-ins and calls as needed. How this engagement starts: I'd like to begin with a paid 1-week trial ($500 fixed). Take my existing React prototype and wrap it in a working Chrome extension that injects a sidebar into Gmail. Connect Gmail OAuth so it can read the user's email. No need to build the full contact graph yet — just prove the extension shell works and can authenticate with Gmail. If the trial goes well, we continue with the full build. To apply, please include: 1. Link to a Chrome extension you've built (published or demo) 2. Brief description of your Gmail API experience 3. How you'd approach the trial task (1-2 sentences) Skip the generic cover letter. I want to see relevant work.

  • $3,000.00

    Fixed-price
  • Intermediate
    Experience Level
  • Remote Job
  • Ongoing project
    Project Type
Skills and Expertise
Mandatory skills
Google Chrome Extension
Activity on this job
  • Proposals:50+
  • Last viewed by client:4 weeks ago
  • Interviewing:
    0
  • Invites sent:
    0
  • Unanswered invites:
    0
About the client
Member since May 4, 2012
  • United States
    Folsom11:56 AM
  • $12K total spent
    59 hires, 0 active
  • 910 hours

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