Full-Stack Team for Multiseller SaaS

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:

Initial technical assessment and proposed architecture

Detailed development plan and milestone schedule

Working application delivered incrementally

Regular progress demonstrations

Access to the source code throughout development

Testing and documentation

Deployment to our nominated infrastructure

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.

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:

A brief introduction outlining your relevant experience.

Examples of at least two SaaS applications you have developed, preferably currently operational.

Details of previous API integration or e-commerce automation projects.

Your recommended technology stack and reasons for choosing it.

Whether you work individually or as part of a team.

Your estimated development timeline.

Your proposed budget and milestone structure.

Your availability to begin.

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.