.NET Developer / Full Stack Developer Needed for Auth Session Issues

Posted 2 hours ago

Worldwide

Summary

Hey, we're a small team (3 devs + me) building a SaaS product on .NET Core / C# with a React frontend. Been live for about 4 months now. The problem: users randomly get logged out even when they were active 2 minutes ago. It's not happening to everyone, and we can't reproduce it consistently, which is exactly why it's driving us crazy. We use JWT with refresh tokens (ASP.NET Core Identity), and our best guess is something in the refresh flow isn't firing when it should, but honestly we've been staring at this for a week and need a second pair of eyes. We're not asking anyone to rebuild our auth from scratch. We need an experienced .NET developer or full stack developer who's actually dealt with this exact JWT/refresh-token pattern before to hop on a call, look at the middleware and the relevant React code, and tell us what's wrong. What we need from you: 30-45 min call to walk through the code together (we'll share screen) Review our token refresh logic in C# / ASP.NET Core Identity Check the React side for anything mishandling token expiry Point us to the actual root cause, not just "add more logging" A short list of what to change, we'll implement it ourselves Good fit if you're a senior .NET developer or C# .NET developer comfortable with .NET Core auth flows. Budget is for 1-2 hours of your time, flat rate or hourly, whatever you prefer. Available for a call today or tomorrow, EU timezone preferred but not required.

  • $300.00

    Fixed-price
  • Intermediate
    Experience Level
  • Remote Job
  • One-time project
    Project Type
Skills and Expertise
Mandatory skills
JavaScript
CSS
HTML5
PHP
Activity on this job
  • Proposals:20 to 50
  • Last viewed by client:20 minutes ago
  • Interviewing:
    2
  • Invites sent:
    0
  • Unanswered invites:
    0
About the client
Member since May 18, 2026
  • Ukraine
    Zaporizhzhia5:13 PM
  • $900 total spent
    2 hires, 0 active

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