Full-Stack Developer — SaaS / Marketplace Platform

Posted 4 hours ago

Worldwide

Summary

## Full-Stack Developer — SaaS / Marketplace Platform We are looking for an experienced **full-stack developer or small development team** to help build an early-stage transactional web platform. The platform will involve multiple user types and combine onboarding, account management, workflow automation, document handling, marketplace/e-commerce functionality, payments, and administrative tools. We already have an initial **architecture plan and product requirements**. We are looking for a developer who can evaluate the existing architecture, identify any concerns or improvements, and then implement the platform using sound, scalable engineering practices. We plan to **start with a limited initial development scope**, with the opportunity for substantial additional work if the relationship and quality of work are a good fit. ### Initial Development The first phase will include: * User registration and authentication * Role-based access and permissions * Multi-step onboarding workflows * Save-and-resume functionality * User/business profiles * Administrative review and approval workflows * Relational database design * Secure document/file uploads * PDF/document generation * Transactional email * Responsive web application * Development, staging, and production environments * Error monitoring * Git-based source control and CI/CD * Secure cloud infrastructure ### Anticipated Technology Stack Our current architecture contemplates: * **Next.js / React** * **TypeScript** * **Tailwind CSS** * **PostgreSQL** * Modern ORM such as **Prisma or Drizzle** * **Clerk** or comparable authentication/authorization * **Amazon S3** for file/document storage * **Vercel** for initial application hosting * **AWS** as the longer-term infrastructure environment * **GitHub** for source control * **Sentry** or comparable application monitoring * Transactional email services * **Stripe / Stripe Connect** in a subsequent phase We are open to well-supported recommendations or changes to this architecture, but developers should be able to explain the technical and business reasons for any proposed changes. ### Architecture Is Important This is intended to become a substantial production platform, not simply a website. We are specifically looking for someone who understands how to architect an application for **portability, maintainability, security, and future scale**. Early architectural decisions should avoid unnecessary vendor lock-in and allow infrastructure to evolve as usage increases **without requiring the core application to be rewritten**. Experience with **AWS architecture and migration** is therefore strongly preferred, even though the initial version may use managed services to accelerate development. ### Future Phases May Include * Multi-vendor marketplace functionality * Vendor/storefront management * Product/menu management * Ordering and inventory * Scheduling and availability * Customer and vendor dashboards * Stripe Connect * Marketplace/platform fees * Payment distribution * Notifications * Administrative tools * Reporting * Workflow automation * Third-party API integrations * Higher-volume cloud infrastructure ### Required Experience Strong experience with: * Next.js / React * TypeScript * PostgreSQL and relational database architecture * Backend/API development * Authentication and role-based authorization * Secure file handling * Git/GitHub workflows * Cloud deployment * Production application security * Database migrations * Dev/staging/production environments Experience with several of the following is highly preferred: * SaaS platforms * Multi-tenant applications * Marketplaces * E-commerce * Stripe Connect * AWS * Amazon S3 * Vercel * Clerk * Transactional email * PDF/document generation * Workflow applications * Applications designed for significant future scale ### Ownership & Development Environment The Company will maintain **ownership and administrative control** of all source-code repositories, cloud/hosting accounts, domains, databases, payment accounts, storage, and other core infrastructure. Development will occur in Company-controlled repositories and environments. Clear, maintainable, documented code is required. ### AI-Assisted Development We are comfortable with responsible use of modern AI development tools such as Claude Code, Codex, Cursor, or similar tools. However, the developer remains responsible for **architecture, security, code quality, testing, licensing, and understanding the code being delivered**. We are not looking for someone whose only development capability is prompting an AI coding tool. ### When Applying Please provide: 1. **2–3 examples of production applications you personally built**, preferably SaaS, marketplaces, e-commerce systems, customer/vendor portals, or transactional platforms. 2. Your **specific role** in each project. 3. The technology stack used. 4. Your experience with **Next.js, TypeScript and PostgreSQL**. 5. Your experience with **AWS and application architecture**. 6. Any experience with **Stripe Connect or marketplace payments**. 7. Experience building applications with multiple user roles and permissions. 8. Whether you work individually or with other developers/subcontractors. 9. Your hourly rate and current availability. 10. How you typically approach architecture for a new application that may need to scale substantially over time. **Please do not submit a generic agency proposal.** We want to communicate directly with the developer(s) who will actually architect and write the application. The selected candidate will initially be asked to **review our existing architecture and requirements** before development begins. Additional information concerning the business model, proprietary workflows, product requirements, and platform will be provided to selected candidates **after execution of a confidentiality agreement**.

  • $15,000.00

    Fixed-price
  • Intermediate
    Experience Level
  • Remote Job
  • Ongoing project
    Project Type
Skills and Expertise
Mandatory skills
AI App Development
API Integration
Activity on this job
  • Proposals:50+
  • Last viewed by client:3 hours ago
  • Interviewing:
    0
  • Invites sent:
    0
  • Unanswered invites:
    0
About the client
Member since Mar 11, 2025
  • USA
    Carlsbad11:58 PM
  • $315 total spent
    2 hires, 0 active
  • Health & Fitness
    Small company (2-9 people)

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