System Architect / Full-Stack Developer — Custom Internal B2B Operating System

Posted yesterday

Worldwide

Summary

About Us We are a wholesale import and distribution company based in the Netherlands. We import ~50 containers per year from China and distribute across Europe under our own brands. We are looking for an experienced system architect / full-stack developer to build a custom internal operating system — the central platform for managing products, customers, quotations, sales follow-up, inventory, suppliers, collections, and daily operations. This is NOT a simple website project. We need someone who thinks in systems, workflows, databases, scalability, and long-term business operations. Current Challenges Product data spread across multiple files and systems Sales follow-up managed through WhatsApp and Excel Quotation generation is fully manual Customer information is fragmented Supplier and shipment information is not centralized Business knowledge depends too much on individuals Goal One centralized operating system where our team manages daily operations — and where WhatsApp conversations stop being a black hole for sales opportunities. Phase 1 (MVP) — Core Modules 1. Product Database SKU, barcode/EAN, product name, category, brand, supplier, multi-tier pricing, images, carton details, documents, product status. 2. PDF Catalog & Quotation Generator ⭐ (top priority) Select products or categories → select customer → generate a branded, professional PDF with customer-specific pricing → save to quotation history. Must look polished, not like a basic export. Multilingual content (EN/NL/AR). 3. Customer CRM Company profile, contacts, WhatsApp number, follow-up history, open balances, credit limit, notes, assigned rep. 4. Sales Follow-Up System Tasks, follow-up reminders, opportunity tracking, pipeline: New → Interested → Waiting → Hot → Confirmed → Lost. 5. Orders Management Quotation → Order workflow with full status tracking. 6. Basic Inventory Available / reserved / incoming stock, low-stock flags. 7. Supplier Records 8. Collections / Payment Tracking Outstanding balances, payment promises, overdue alerts. 9. Owner Dashboard Hot leads, overdue follow-ups, pending orders, stock issues, outstanding collections, missing product data. WhatsApp — Very Important to Us ⭐ WhatsApp is where most of our customer conversations happen. We want the platform to be WhatsApp-native, in two stages: Stage A (architecture ready in Phase 1, built in Phase 2): Official WhatsApp Business API (Meta Cloud API) integration Inbound messages matched to customers by phone number Messages become leads, tasks, or follow-ups inside the CRM Outbound messages (quotes, payment reminders, order updates) sent from the platform using approved templates Stage B — AI Auto-Reply (key future feature): We want an AI assistant that replies to customers the way our team replies — same tone, same product knowledge, same pricing logic — trained on our real conversations and product database. It should handle first responses, product questions, and price requests, and escalate to a human when needed. In your proposal, tell us realistically: Which BSP/provider you'd use (Meta Cloud API direct, Twilio, 360dialog, other) and why What the WhatsApp API can and cannot do vs. normal WhatsApp How you would architect the AI auto-reply (model, training on our data, guardrails, human handoff) Real limitations and risks (template approval, number restrictions, Meta policies) We want an honest technical plan, not promises. If someone tells us "everything is possible, no problem" — that's a red flag for us. Future Phases Shipment/container tracking · Supplier portal (China factories upload documents) · B2B customer portal · Marketplace integrations (Bol.com, Marktplaats, Faire, Ankorstore, Orderchamp, Zentrada) · Accounting integrations · Advanced AI dashboard. The Phase 1 architecture must support all of this from day one. Preferred Tech Stack Open to recommendations. Current preference: Next.js (React) PostgreSQL / Supabase Server-side PDF generation Standard hosting (Vercel, AWS, Render) — all accounts and code owned by us, no lock-in ⭐ Stand Out: Show Us a Working Example Applicants who include a small working demo will be prioritized and get a much faster response. For example: a mini product database (5–10 sample products) with a generated branded PDF catalog or quotation. It doesn't need to be big — we want to see how you think and the quality of your output. A link to a live demo or a short screen recording is perfect. Portfolios and case studies of similar systems (CRM, ERP, B2B platforms, internal tools) are also strongly valued. Requirements — Include in Your Proposal Similar systems you have built (with links/screenshots) Your exact role in those projects Team structure — solo or team? Who writes the code? Suggested architecture Estimated timeline for Phase 1 Estimated budget for Phase 1 (fixed price, milestone-based) Build from scratch vs. existing framework — and why How you'd handle scale: 10,000+ products, multiple users, supplier/customer portals later Your realistic WhatsApp Business API + AI auto-reply plan Confirmation: we own all code, data, accounts, and credentials from day one Important We are looking for a long-term technical partner, not a freelancer building screens. The ideal candidate understands CRM systems, ERP workflows, wholesale operations, inventory concepts, supplier management, and business process automation. Milestone-based payment. No full payment before working software is visible. Working demo with your application = fastest path to getting hired. No copy-paste proposals — we will ignore them. Start your proposal with the word "OPERATOR" so we know you read this.

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

    -

    $35.00

    Hourly
  • Remote Job
  • Ongoing project
    Project Type

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Skills and Expertise
Mandatory skills
Web Application
Website Redesign
Activity on this job
  • Proposals:50+
  • Last viewed by client:yesterday
  • Interviewing:
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About the client
Member since Apr 11, 2024
  • Netherlands
    11:09 AM

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