Senior Full-Stack Developer / Development Team – E-commerce SaaS Platform

# Senior Full-Stack Developer / Development Team – E-commerce SaaS Platform **Project Type:** Custom Web Application / SaaS Development **Engagement:** Fixed-price, milestone-based **Location:** Remote / Worldwide **Potential:** Long-term development and maintenance ## Project Overview We are seeking an experienced full-stack developer or small development team to design and build a modern, scalable, cloud-based SaaS platform focused on e-commerce operations, third-party integrations and business process automation. The platform will provide users with a centralised interface to manage data, integrations and automated workflows across external services. We have a clear product direction and will provide detailed functional requirements to shortlisted candidates following initial discussions and a confidentiality agreement. The successful developer will be responsible for delivering a professional, secure, reliable and commercially deployable application. ## Scope of Work The initial development phase will include: **1. SaaS Application Development** - Modern, responsive web application - Secure user registration, login and authentication - User dashboard and account management - Multi-tenant architecture supporting independent customer accounts - Role-based permissions where required - Subscription and billing integration **2. Third-Party API Integrations** - Integration with external e-commerce platforms - Integration with third-party data providers - Secure API authentication and credential management - Data retrieval, processing and synchronisation - Webhook handling and scheduled background tasks - Appropriate API rate-limit handling **3. Workflow Automation** - Configurable automated processes - Scheduled and event-driven operations - Data validation and processing - Error handling, retries and logging - Monitoring and notification capabilities **4. Administration and Reporting** - Customer-facing dashboard - Administrative management interface - Operational reporting - Activity history and audit logs - Basic performance monitoring **5. Testing and Deployment** - Frontend and backend testing - API integration testing - Security and performance testing - Cloud deployment and configuration - Technical documentation - Bug fixes and post-launch support ## Preferred Technology Stack We are open to recommendations but prefer modern, widely supported technologies. - **Frontend:** React / Next.js / TypeScript - **Backend:** Node.js / TypeScript - **Database:** PostgreSQL / Supabase - **Hosting:** Vercel, AWS or equivalent - **Version Control:** GitHub - **Payments:** Stripe - **Architecture:** Scalable, modular and API-driven Developers should explain any proposed alternative technologies and their advantages. ## Required Experience Applicants must demonstrate proven experience in: - Developing commercial SaaS applications - Building complex API integrations - E-commerce platform integrations, preferably Shopify - Database design and multi-tenant architecture - Workflow automation and background processing - Secure authentication and payment integration - Deploying and maintaining production web applications Experience with inventory systems, order management, data synchronisation or similar integration-heavy applications is highly desirable. ## Project Delivery Requirements We require a structured development approach with clearly defined milestones. The successful applicant must provide: 1. Initial technical assessment and proposed architecture 2. Detailed development plan and milestone schedule 3. Working application delivered incrementally 4. Regular progress demonstrations 5. Access to the source code throughout development 6. Testing and documentation 7. Deployment to our nominated infrastructure 8. Agreed post-launch defect support All source code, custom designs, documentation and intellectual property developed specifically for this project must be transferred to the client upon payment, subject to agreed third-party and open-source licensing. Development must take place in a GitHub repository controlled by the client. Hosting, database and other production accounts will also remain under client ownership. ## Confidentiality The project involves a proprietary commercial concept. Detailed product specifications, business logic, workflows and integration requirements will be shared only with shortlisted candidates under an appropriate confidentiality agreement. Applicants should be comfortable working under an NDA and signing an agreement covering intellectual property ownership. ## Budget and Timeline We are open to proposals based on a clearly defined MVP scope. Please provide a realistic development timeline, estimated cost and recommended team structure. Payments will be made through agreed milestones following demonstration, testing and acceptance of deliverables. ## How to Apply Please include the following in your proposal: 1. A brief introduction outlining your relevant experience. 2. Examples of at least two SaaS applications you have developed, preferably currently operational. 3. Details of previous API integration or e-commerce automation projects. 4. Your recommended technology stack and reasons for choosing it. 5. Whether you work individually or as part of a team. 6. Your estimated development timeline. 7. Your proposed budget and milestone structure. 8. Your availability to begin. 9. Your approach to testing, security and ongoing maintenance. **Important:** Generic or automated proposals without relevant project examples will not be considered. We are looking for a reliable, technically capable development partner who can deliver high-quality work and potentially support the platform as it grows.