FastAPI + React Lead Engineer — SaaS Platform, Path to Pilot Launch

Posted yesterday

Worldwide

Summary

We need a full-stack engineer to take an existing, working SaaS platform to a pilot-ready MVP. APEX Dealer OS is an operational accountability platform for automotive dealerships — real-time task ownership, escalations, and workflow visibility across sales, service, recon, and delivery. The core is already built and functional: FastAPI + MongoDB backend, React frontend, JWT auth with role-based access, multi-tenant data separation, and a working AI layer (Claude-powered insights and predictions). Backend tests are passing. This is not a build-from-scratch project. We need someone who can assess the existing codebase, harden it for production, and close specific known gaps: Fix a CORS security misconfiguration (quick, but must happen before real data) Move from a dev/preview environment to real production hosting, database, and domain Wire up live SMS via Twilio (currently mocked/console-logged only) Refactor a ~5,000-line single backend file into proper modules Close a handful of known, documented gaps (missing routes, untested paths) Timeline: targeting a working MVP in ~8 weeks, feeding into a 60-day pilot with real dealership customers. First deliverable: before writing code, a written assessment of the existing codebase — what's solid, what needs rework, and your own realistic timeline given the priorities above. We're a lean, founder-led team. You'll be working independently and owning technical decisions, not waiting on a large engineering org for direction.

  • Less than 30 hrs/week
    Hourly
  • 1-3 months
    Duration
  • Expert
    Experience Level
  • $25.00

    -

    $50.00

    Hourly
  • Remote Job
  • Complex 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
Python
MongoDB
Twilio API
Activity on this job
  • Proposals:50+
  • Last viewed by client:1 hour ago
  • Interviewing:
    4
  • Invites sent:
    22
  • Unanswered invites:
    18
About the client
Member since May 6, 2026
  • USA
    Mahwah8:56 PM
  • $300 total spent
    1 hire, 0 active
  • Automotive
    Small company (2-9 people)

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