Full-Stack Developer — B2B SaaS / Automation Platform

Posted 2 days ago

Worldwide

Summary

We are looking for an experienced *Full-Stack Developer based in Latin America* to join our development team and help evolve an existing consumer-facing technology platform into a scalable B2B SaaS and automation solution. Our platform is currently designed primarily for *B2C use* and is already operational. We are now expanding the technology so it can support multiple B2B clients, white-label environments, configurable deployments, and more scalable automation. You will work *under our Senior Full-Stack Developer* and alongside our business and operations team to help build, improve, test, and support this transition. ## What You'll Work On You will help us: * Enhance an existing B2C platform for scalable B2B use * Build reusable functionality that can support multiple client environments * Help improve white-label and client-specific configuration capabilities * Develop and maintain third-party API integrations * Support B2B client deployments and technical onboarding * Troubleshoot API, backend, frontend, and production issues * Improve internal automation and operational workflows * Build and improve administrative tools and dashboards * Improve user roles, permissions, and account management functionality * Support real-time application functionality * Improve platform reliability, scalability, and maintainability * Help reduce manual work required when onboarding new B2B clients * Implement features and architecture designed by our Senior Full-Stack Developer ## Technical Experience We're Looking For Our platform uses a modern JavaScript/TypeScript stack. Strong experience with the following is preferred: * Node.js / Express * React + TypeScript * MongoDB / Mongoose * REST APIs and third-party integrations * Authentication and authorization * WebSockets / real-time functionality * Tailwind CSS or similar frontend frameworks * React state management * Background jobs and automated processes * File handling and uploads * Git-based development * Debugging live production applications Experience with *multi-tenant SaaS, white-label platforms, automation systems, fintech, gaming technology, or transaction-heavy applications* is a major plus. ## B2C to B2B Expansion A major focus of this role will be helping us convert functionality that currently works for one consumer-facing platform into technology that can reliably support multiple independent B2B clients. This may include areas such as: * Tenant or client-level configuration * Client-specific branding and settings * Role and permission management * Reusable integrations * Client-specific credentials and configurations * Standardized deployment processes * Centralized administration * Automation of onboarding tasks * Platform monitoring and troubleshooting * Reducing client-specific custom development You do not need to independently architect the entire system. Our *Senior Full-Stack Developer will provide technical direction and oversee the platform architecture*, but we are looking for someone capable of understanding that architecture, contributing ideas, and independently executing development work. ## What We're Looking For We want someone who is comfortable working inside an existing codebase rather than only building new projects from scratch. You should be able to: * Understand unfamiliar systems quickly * Follow an established technical architecture * Write clean, maintainable code * Troubleshoot issues independently * Work from business requirements and technical specifications * Communicate blockers clearly * Collaborate closely with a senior developer * Identify potential scalability or reliability issues * Take ownership of assigned development work Strong API troubleshooting skills are especially important. ## Location & Availability We are specifically looking for developers located in *Latin America* because we want strong overlap with U.S. Eastern Time business hours. This is intended to be an *ongoing, long-term position* rather than a short-term freelance project. For the right developer, the role can grow as our B2B technology offering expands. ## To Apply Please include: 1. Your location and timezone 2. Years of full-stack development experience 3. Experience with Node.js, React, TypeScript, and MongoDB 4. An example of a SaaS, automation, API-heavy, or multi-tenant system you've worked on 5. Your experience integrating and troubleshooting third-party APIs 6. Any experience converting a single-product application into a multi-client or multi-tenant platform 7. Your typical working hours and availability 8. Your hourly rate 9. GitHub, portfolio, or relevant project examples if available Please begin your application with the phrase *"B2B Platform"* so we know you read the full posting

  • More than 30 hrs/week
    Hourly
  • 6+ months
    Duration
  • Intermediate
    Experience Level
  • Remote Job
  • Ongoing project
    Project Type

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Skills and Expertise
Mandatory skills
Node.js
React
TypeScript
Activity on this job
  • Proposals:50+
  • Interviewing:
    0
  • Invites sent:
    0
  • Unanswered invites:
    0
About the client
Member since Jun 17, 2025
  • USA
    Decatur7:01 PM
  • $28K total spent
    14 hires, 4 active
  • 1,701 hours

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