ScrapFlow SA

The complete scrap metal management platform for South African scrapyards

SAPS/ITAC compliant · Real-time · Multi-site · Production-ready

Live Demo  ·  API Docs  ·  Report Bug

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Note

Try the live demo instantly — no sign-up needed. Use any of the test accounts below:

Role	Email	Password
Owner (full access)	owner@scrapflow.co.za	ScrapFlow@2026!
Manager	manager@scrapflow.co.za	ScrapFlow@2026!
Scale Operator	scale@scrapflow.co.za	ScrapFlow@2026!
Grader	grader@scrapflow.co.za	ScrapFlow@2026!
Accountant	accounts@scrapflow.co.za	ScrapFlow@2026!

Frontend: https://scrap-flow-xi.vercel.app/  |  API: https://scrapflow-api.onrender.com

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The Problem vs. The Solution

South African scrapyards face three existential threats from legacy pen-and-paper operations:

Pain Point	Before ScrapFlow	After ScrapFlow
Compliance Chaos	Paper registers fail SAPS audits → fines & license revocation	Compliance baked into code — ticket cannot complete without EFT ref + ID photos
Operational Blindness	No real-time tonnage or profit visibility	Live dashboard with inventory value, revenue, and ticket stats
Cash Ban Burden	Manual EFT tracking is error-prone and un-auditable	Integrated payment workflow with verified references and 5-year audit trail

The South African Second-Hand Goods Act and the 2024/2025 Metal Cash Ban require strict digital record-keeping. ScrapFlow acts as a Digital Auditor — hard-blocking non-compliant actions at the service layer.

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Features

Category	Feature	Detail
Compliance	Cash-ban enforcement	Blocks ticket completion without a verified EFT reference
Compliance	Mandatory photo capture	3 required photos: Seller ID, Load, Proof-of-Payment
Compliance	5-year audit trail	Rolling registers stored per SAPS/ITAC requirements
Operations	6-step inbound ticket	Arrive → Gross Weigh → Grade → Tare → Pay → Complete
Operations	Outbound tickets	Full customer invoice workflow with lot selection
Inventory	Real-time lot tracking	Automatic lot creation on ticket completion
Inventory	Adjust & write-off	Manager-approved lot adjustments with reason logging
Real-time	SignalR inventory hub	Live updates pushed to all connected clients instantly
Automation	Webhook system	Fires on ticket/inventory events → Zapier, n8n, Make
UX	Offline-first PWA	IndexedDB drafts survive connectivity loss
UX	Weighbridge integration	Web Serial API direct industrial scale communication
Admin	5-role RBAC	Owner / Manager / ScaleOp / Grader / Accountant
Admin	Multi-site support	Manage multiple scrapyards from one account
Reports	Revenue & tonnage reports	Filterable by site, date range, and material grade

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Tech Stack

Backend	Frontend
ASP.NET Core 8 (Clean Architecture)	React 18 (JSX + Vite)
Entity Framework Core 8	Tailwind CSS + Glassmorphism UI
PostgreSQL (Supabase)	Zustand state management
SignalR (real-time hubs)	@microsoft/signalr client
JWT authentication (12h tokens)	Axios + React Query patterns
HMAC-SHA256 webhook signing	Web Serial API (weighbridge)
Serilog structured logging	IndexedDB offline drafts
Docker + docker-compose	Deployed on Vercel

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Architecture

graph TD
    Client["React Client\n(Vercel)"]
    API["ScrapFlow.API\n(Render)"]
    APP["ScrapFlow.Application\nDTOs · Interfaces · Services"]
    DOMAIN["ScrapFlow.Domain\nEntities · Enums · Business Rules"]
    INFRA["ScrapFlow.Infrastructure\nEF Core · Migrations · Services"]
    DB[("PostgreSQL\n(Supabase)")]
    SIG["SignalR Hubs\nInventory · Tickets"]
    HOOK["Webhook Service\nHMAC-SHA256 signing"]
    N8N["n8n / Zapier\nAutomation workflows"]

    Client -- "REST + SignalR" --> API
    API --> APP
    APP --> DOMAIN
    INFRA --> APP
    INFRA --> DOMAIN
    INFRA --> DB
    API --> SIG
    API --> HOOK
    HOOK -- "HTTP POST" --> N8N

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Deployment

Layer	Platform	Notes
Frontend	Vercel	Auto-deploys on push to main
Backend API	Render	Dockerized ASP.NET Core 8
Database	Supabase	Managed PostgreSQL
Automation	n8n (Docker) + Zapier	4 pre-built workflow templates

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Engineering Challenges & Solves

1. Circular Dependency in Clean Architecture

Problem: During the Application/Infrastructure split, services needed DbContext but DbContext needed service logic — a circular reference. Solution: Moved TicketService into the Infrastructure layer, implementing interfaces defined in Application. Maintained Clean Architecture principles while resolving the cyclic reference.

2. Dependency Injection & Service Scoping

Problem: Standalone services threw runtime errors due to missing ILogger implementations and improper DI registrations. Solution: Standardized all DI registrations in Program.cs using generic ILogger<T>. In unit tests, used Moq to provide verified mock loggers — isolating business logic from external providers.

3. In-Memory Database Versioning

Problem: The xUnit test suite failed because InMemoryDatabase v10 was incompatible with the .NET 8 target. Solution: Manual downgrade to Microsoft.EntityFrameworkCore.InMemory v8.0.0, aligning test infrastructure with the core runtime.

4. Non-Blocking Webhook Dispatch

Problem: Firing webhooks synchronously would add latency to every ticket completion HTTP response. Solution: Implemented fire-and-forget using _ = Task.Run(() => _webhookService.FireAsync(...)) — the HTTP response returns immediately while the webhook dispatches in the background. HMAC-SHA256 signature header ensures receiver authenticity.

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What I Learnt

1. Industry-Specific Architecture — Translating legal requirements (SAPS/ITAC) into strict software guards and validation logic at the service layer.
2. Browser-Hardware Interfacing — Using the Web Serial API to bridge industrial weighbridge hardware and modern web browsers without drivers.
3. Offline-First Resilience — PWA strategies with Service Workers + IndexedDB to handle South African connectivity instability.
4. Clean Architecture Discipline — Maintaining strict separation of concerns even when complex infrastructure dependencies arise in real-world projects.
5. Real-time Systems — Building SignalR hubs with group-based broadcasting (per-site) and stable client reconnection handling.

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Getting Started (Local Dev)

Prerequisites

• .NET 8 SDK
• Node.js 18+
• Docker Desktop

1. Clone & configure

git clone https://github.com/dev-k99/ScrapFlow.git
cd ScrapFlow
cp src/ScrapFlow.API/appsettings.example.json src/ScrapFlow.API/appsettings.json
# Edit appsettings.json — add your PostgreSQL connection string and JWT secret

2. Docker quick start

docker compose up --build
# API: http://localhost:5010
# n8n: http://localhost:5678

3. Or run individually

# Backend
cd src/ScrapFlow.API && dotnet run

# Frontend
cd scrapflow-client && npm install && npm run dev
# → http://localhost:5173

4. Seed data

On first run, the API automatically seeds:

• 5 user accounts (Owner, Manager, ScaleOp, Grader, Accountant)
• 2 sites (Germiston Main Yard, Durban North Depot)
• 20 material grades (ferrous + non-ferrous) with realistic ZAR prices
• 10 suppliers + 3 customers + 5 sample completed tickets

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API Reference

Resource	Method	Endpoint	Auth
Auth	POST	/api/auth/login	Public
Auth	POST	/api/auth/register	Public
Dashboard	GET	/api/dashboard?siteId=	Any role
Inbound Tickets	POST	/api/tickets/inbound	ScaleOp+
Inbound Tickets	PUT	/api/tickets/inbound/{id}/gross-weight	ScaleOp+
Inbound Tickets	PUT	/api/tickets/inbound/{id}/grading	Grader+
Inbound Tickets	PUT	/api/tickets/inbound/{id}/payment	Accountant+
Inbound Tickets	PUT	/api/tickets/inbound/{id}/complete	Manager+
Outbound Tickets	GET/POST	/api/tickets/outbound	ScaleOp+
Inventory	GET	/api/inventory?siteId=&status=	Any role
Inventory	PUT	/api/inventory/{id}/adjust	Manager+
Inventory	PUT	/api/inventory/{id}/write-off	Manager+
Materials	GET	/api/materials	Any role
Suppliers	GET/POST	/api/suppliers	ScaleOp+
Customers	GET/POST	/api/customers	ScaleOp+
Reports	GET	/api/reports	Manager+
Webhooks	GET/POST/DELETE	/api/webhooks	Owner only
Sites	GET/POST	/api/sites	Owner (POST)
Audit Log	GET	/api/auditlogs	Manager+
Health	GET	/health	Public

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Designed & Engineered for South African Scrapyards

Built by Kwanele Ntshangase · Live Demo · View Source