MI-Technologies — Confidential

MI-Proc Platform

High-Level Design (HLD)

B2B Construction Procurement Marketplace · Multi-Tenant Whitelabel · Mi-Wallet Escrow & Settlement

Version: 1.2 Draft

Date: 8 June 2026

Status: Pending ARB sign-off

Classification: Confidential

B2B Marketplace
Multi-Tenant Whitelabel
SAMA Escrow
KSA Data Residency
1. Purpose & Document Scope2. Architectural Philosophy3. Master Architecture — Layered View4. Design Risk Register5. Edge & Security Layer6. Event Backbone (Kafka)7. Microservice Communication8. SAGA Orchestration9. Microservice Architecture Types10. Domain Service Catalogue11. SAGA Service Catalogue12. Platform & Integration Services13. Real-Time Layer (Socket Service)14. Frontend Standards15. Technology Stack16. DevOps & Deployment17. QA & Test Strategy18. Security, Compliance & Governance19. Glossary

This HLD is the single authoritative architectural reference for the MI-Proc platform. It defines architectural principles, engineering standards, integration contracts, microservice specifications, and operational guardrails governing every component.

What MI-Proc is: Two tightly-integrated products on one platform — (1) the MI-Proc Marketplace: anonymous, AI-matched B2B RFQ-and-bidding marketplace for Saudi construction materials with escrowed settlement; and (2) an independent, multi-tenant whitelabel procurement system sold to SMEs, natively integrated so approved purchase requisitions can be sourced through the marketplace.

The platform spans two payment eras: today a licensed third-party bank/PSP acts as escrow agent; in future MI-Technologies' own SAMA-licensed EMI wallet replaces it. The marketplace and procurement domains are insulated from which era is in force.

TeamHow to use this HLD
Backend (.NET)Sections 6–12: DDD + Onion, one-DB-per-service, Outbox, idempotency; build each service per §10–§12
Frontend (React/RN)Sections 5, 13, 14: consume BFF only; honour whitelabel theming and server-driven config
IntegrationSections 4.1, 4.4, 12: external systems behind ACL with contract tests
DevOps/SRESections 15–16: K8s topology, KSA data residency, CI/CD MUST-gates, Elastic APM, secrets, DR
QASection 17: test pyramid and mandatory per-service scenarios (idempotency, tenant-isolation, contract, chaos)
Security/ComplianceSections 4, 5.4, 18: audit immutability, PII tokenisation, RBAC + maker-checker, dual-token, regulation mapping
ARBSection 19: gate new services; require ADR and Defense-of-Design row
Conventions: MUST/SHALL = non-negotiable, violations block release. SHOULD = strongly recommended. MAY = optional. Deviations from MUST require: (1) ADR, (2) Principal Engineer + ARB sign-off, (3) compensating control, (4) tech-debt register entry with deadline.

MI-Technologies — Confidential · MI-Proc Platform HLD v1.2 Draft · 8 June 2026

This document is confidential and proprietary to MI-Technologies. Distribution is restricted to named recipients.