Senior Full Stack Developer Needed for SaaS Bug Fixes & Ongoing Improvements

Posted 3 weeks ago

Worldwide

Summary

We are looking for an experienced Full Stack Developer to help identify, troubleshoot, and resolve bugs in an existing SaaS application. The platform is already live and actively used by customers. We need a developer who can quickly understand an existing codebase, diagnose issues efficiently, and implement reliable fixes without introducing new problems. This role may lead to ongoing work for feature enhancements and long-term maintenance. Responsibilities ✅ Investigate and fix frontend and backend bugs ✅ Debug API integrations and third-party services ✅ Resolve UI/UX issues across desktop and mobile devices ✅ Fix database-related issues and performance bottlenecks ✅ Improve application stability and reliability ✅ Review logs, error reports, and application behavior ✅ Test fixes thoroughly before deployment ✅ Collaborate on future improvements and optimizations Required Skills Frontend React.js Next.js TypeScript JavaScript Tailwind CSS Backend Node.js Express.js REST APIs Database PostgreSQL MongoDB Additional Git/GitHub API Integrations Debugging & Troubleshooting SaaS Application Experience Ideal Candidate You should be able to: ✔️ Quickly understand existing codebases ✔️ Work independently with minimal supervision ✔️ Communicate technical findings clearly ✔️ Deliver clean and maintainable fixes ✔️ Think critically and identify root causes rather than temporary workarounds ✔️ Follow best practices for testing and deployment Nice to Have ⭐ SaaS product experience ⭐ AWS experience ⭐ Docker experience ⭐ CI/CD knowledge ⭐ Performance optimization experience ⭐ AI/OpenAI integration experience Project Details Existing SaaS application Immediate bug-fixing work required Potential long-term collaboration Flexible working hours Remote When Applying Please include: A brief summary of your SaaS experience. Examples of bug-fixing or maintenance work you've completed. Your strongest technology stack. Your availability this week. Your hourly rate. Please start your proposal with the word "BUGFIX" so we know you've read the entire job description. We look forward to working with you.

  • Less than 30 hrs/week
    Hourly
  • 1-3 months
    Duration
  • Intermediate
    Experience Level
  • $30.00

    -

    $40.00

    Hourly
  • Remote Job
  • Ongoing project
    Project Type
Skills and Expertise
Mandatory skills
Next.js
Facebook JavaScript
Activity on this job
  • Proposals:50+
  • Last viewed by client:2 weeks ago
  • Hires:
    1
  • Interviewing:
    0
  • Invites sent:
    0
  • Unanswered invites:
    0
About the client
Member since Mar 21, 2026
  • United States
    Los Angeles4:57 PM
  • $746 total spent
    25 hires, 0 active
  • 6 hours

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