Senior Full Stack Web Developer – Website, SaaS & Web Application Development

Posted 9 hours ago

Worldwide

Summary

We're looking for an experienced Senior Full Stack Web Developer to help us build and improve a modern website and web application. This isn't just a frontend website project. We need someone who can handle the complete stack, from a clean, responsive user interface and frontend development to backend architecture, databases, APIs, authentication, integrations, and deployment. We're starting with a focused first phase, but the goal is to build a solid foundation that can be expanded over time. What You'll Work On - Build responsive, modern websites and web application interfaces - Develop frontend features using React, Next.js, TypeScript, JavaScript, HTML, CSS, and Tailwind CSS - Build backend services and business logic using Node.js / Express.js - Design and integrate REST APIs and third party APIs - Work with PostgreSQL, MySQL, MongoDB, or similar databases - Set up database schemas, relationships, queries, and optimization - Implement user authentication, authorization, RBAC, OAuth, and JWT - Connect external services and APIs - Build forms, dashboards, user accounts, and dynamic application features - Handle server side logic and background processes - Add real time functionality where required - Improve website and application performance - Debug existing issues and handle technical improvements - Test features and make sure everything works properly across devices Architecture & Advanced Development We're looking for someone who understands more than just writing code. Experience with the following is highly valuable: - SaaS application development - Scalable web application architecture - Multi tenant applications - Microservices and modular architecture - Event driven architecture - WebSockets and real time applications - Redis and caching - GraphQL - Background jobs and queues - Serverless functions - API security and rate limiting - Performance optimization - Automated testing and error handling Cloud & Deployment Experience with modern deployment and infrastructure is a strong plus: - AWS - Vercel - Docker - Git / GitHub - CI/CD - AWS Lambda - S3 - CloudFront - Cloud databases - Serverless architecture - Monitoring, logging, and application security Integrations The application may require integrations with external services such as: - Payment platforms - CRM systems - Email services - Automation platforms - AI / LLM APIs - Analytics tools - Other REST or GraphQL APIs Experience with Stripe, OpenAI API, Supabase, Firebase, Twilio, webhooks, and third party API integrations is a plus. What We're Looking For We're looking for a developer who can take ownership of the technical side of the project rather than simply completing individual tickets. You should be comfortable making decisions around frontend development, backend development, database architecture, API design, security, performance, scalability, and deployment. Strong communication and clean, maintainable code are important to us. To Apply Please send 2 to 3 relevant websites or web applications you've built. For each project, briefly tell us: - What you personally worked on - Frontend and backend technologies used - Database and API integrations - Any challenging features you implemented If you've worked on SaaS platforms, marketplaces, dashboards, AI powered applications, payment systems, or complex web applications, feel free to include those examples. We're starting with a focused first phase and are looking for someone who can help us build it properly from the beginning.

  • Less than 30 hrs/week
    Hourly
  • 1-3 months
    Duration
  • Intermediate
    Experience Level
  • $15.00

    -

    $35.00

    Hourly
  • Remote Job
  • Ongoing project
    Project Type

Contract-to-hire opportunity

This lets talent know that this job could become full time.
Learn more
Skills and Expertise
Mandatory skills
JavaScript
PHP
Web Development
Activity on this job
  • Proposals:50+
  • Last viewed by client:4 hours ago
  • Hires:
    1
  • Interviewing:
    2
  • Invites sent:
    0
  • Unanswered invites:
    0
About the client
Member since Feb 20, 2026
  • United States
    Houston5:23 PM
  • $3.8K total spent
    103 hires, 6 active
  • 116 hours
  • Health & Fitness
    Individual client

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