Senior Full Stack Developer

Posted 3 hours ago

Worldwide

Summary

We are looking for an experienced Senior Full Stack Developer to improve and expand our existing CRM platform. The ideal candidate has strong expertise in modern JavaScript frameworks, backend development, AI integrations, payment systems, and software testing. You will be responsible for implementing new features, optimizing performance, fixing complex issues, and ensuring the platform remains scalable and secure. Required Skills React.js Next.js Node.js Python OpenAI API integration Stripe payment integration REST APIs and third-party API integration SQL and NoSQL databases Git/GitHub Unit testing and end-to-end testing Debugging and performance optimization Responsibilities Improve and maintain an existing CRM application. Develop new frontend and backend features. Build clean, reusable, and scalable code. Integrate OpenAI APIs for AI-powered CRM functionality. Implement and maintain Stripe payment workflows, including subscriptions and payment processing. Design and integrate RESTful APIs. Identify and fix bugs, security issues, and performance bottlenecks. Write unit and integration tests to ensure software quality. Collaborate with stakeholders to understand business requirements and deliver high-quality solutions. Review code and follow best development practices. Qualifications 5+ years of full-stack development experience. Strong proficiency in React.js, Next.js, Node.js, and Python. Proven experience integrating OpenAI APIs into production applications. Hands-on experience with Stripe payment gateway and subscription billing. Experience with authentication, authorization, and secure application development. Strong understanding of database design and optimization. Experience with testing frameworks and automated testing. Excellent problem-solving and communication skills. Preferred Skills Experience with CRM systems or SaaS products. Experience deploying applications on AWS, Azure, or Google Cloud. Familiarity with Docker and CI/CD pipelines. Experience working in Agile/Scrum environments. What We're Looking For Strong attention to detail. Ability to work independently and deliver high-quality code. Excellent communication and documentation skills. Commitment to writing maintainable, scalable, and well-tested software. If you have successfully built or improved CRM platforms with AI capabilities and payment integrations, we'd love to hear from you. Please include examples of similar projects, your tech stack, and links to relevant GitHub repositories or portfolio work.

  • $20.00

    Fixed-price
  • Expert
    Experience Level
  • Remote Job
  • Ongoing project
    Project Type
Skills and Expertise
Mandatory skills
OpenAI API
Next.js
Node.js
Activity on this job
  • Proposals:Less than 5
  • Last viewed by client:2 hours ago
  • Hires:
    1
  • Interviewing:
    0
  • Invites sent:
    1
  • Unanswered invites:
    0
About the client
Member since Jul 11, 2026
  • Pakistan
    Lahore10:52 PM

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