May 2013 – Oct 2017

Re-architecting a Legacy ERP into a Scalable Microservices Platform

Sysco Guest Supply · Full Stack Developer

30,000+

Products Managed

14+

VCM Modules

Years, → Team Lead

PeopleSoft

Legacy ERP Retired

Growth & Stability

~60%

API Response Time Reduced

30+

Manual Workflows Eliminated

1000s

Real-time Synced Users

Overview

Sysco Guest Supply is a large-scale hospitality-amenities supplier, and its platform is Guest Supply's Value Chain Management (VCM) portal. It began as a vendor-compliance portal and grew module by module into a full multi-tenant ERP managing 30,000+ products across seven categories, ultimately absorbing and retiring the legacy Oracle PeopleSoft ERP. I led its transformation from a .NET WebForms monolith into a modern, scalable microservices platform.

The Problem

Poor architecture due to years of incremental changes

Frequent instability and performance bottlenecks

Heavy reliance on manual database interventions to maintain workflows

Rigid system that slowed down feature development

Complex, inconsistent database schema

Limited scalability and difficult team collaboration

The Solution

Built a modern microservices-based backend using .NET Core

Designed a clean, optimized SQL Server schema

Implemented a phased migration with parallel system execution

Introduced strict data validation and workflow automation

Rebuilt frontend from .NET WebForms → AngularJS → Vue.js

Grew a vendor-compliance portal module by module into a full ERP, absorbing and retiring the legacy Oracle PeopleSoft system

Ran the platform on a period-accurate (2013–2017) Azure stack: App Services, App Service Environment, Application Gateway, Service Bus, Azure SQL, Key Vault, VNet + NSGs

Migrated the main applications to AWS, aligning with parent company Sysco's AWS standard

Architecture

Core Components

Vendor Compliance — supplier onboarding, qualification & self-assessment auditsItem Management — product catalog & specification managementProduct Development — stage-gated PD workflow (ideation → RFQ → testing → approval → production)Hospitality Product Programs — brand-aligned order guides for new hotelsEnterprise Project Management (EPMO) — financial (ROI, IRR, breakeven, cash flow) & marketing (SWOT, 5 Forces) analysesTest Management — QA plus training assessments (materials + MCQ exams)Logistics, Label Management, Change Management, Opportunity ManagementProcess Scheme, Meeting Management, User Management (RBAC), Setup

Technical Design

Microservices-based backend (.NET Core)

API Gateway for centralized routing

REST + queue-based communication

Azure platform: App Services / Web Apps, App Service Environment, Azure VMs, Service Bus, Azure SQL, Key Vault, Storage

Azure networking: Application Gateway (L7 + SSL), Virtual Network + NSGs; egress via Load Balancer SNAT and a Linux network virtual appliance (iptables SNAT)

Identity & ops: Azure AD (now Entra ID), App Registrations, Log Analytics, Power BI

Dual-cloud: main applications migrated to AWS (parent company Sysco's standard)

Multi-tenant system design

Advanced RBAC (role-based access control)

Dynamic form builder for no-code workflow creation

Full audit logging and change tracking

My Role: Backend Developer → Team Lead

Designed backend architecture and microservices structure

Led full rewrite of legacy ERP system

Owned API design, development, and integration

Solved critical performance bottlenecks in legacy system

Led data migration strategy across inconsistent schemas

Reviewed PRs and enforced code quality standards

Mentored junior developers and scaled team productivity

Planned releases and coordinated cross-team delivery

Operated the Azure infrastructure and led migration of the main apps to AWS

Key Achievements

🔥

Grew a vendor-compliance portal into a full multi-tenant ERP, retiring the legacy Oracle PeopleSoft system

🔥

Managed 30,000+ products across seven top-level categories

🔥

Rewrote an entire enterprise ERP system with 30+ modules

🔥

Transformed monolithic WebForms app into microservices architecture

🔥

Enabled parallel system migration without business disruption

🔥

Eliminated manual database interventions through automation

🔥

Built a flexible system with dynamic workflows and form builder

🔥

Improved developer velocity through modular architecture

Impact

📊

Significant performance improvements due to optimized schema and architecture

📊

Major increase in system reliability and stability

📊

Reduced manual operational overhead through automation

📊

Enabled independent development across teams using microservices

📊

Delivered a modern, scalable ERP supporting internal teams, vendors, and customers

📊

Dramatically improved UI/UX with AngularJS and Vue.js transition

Tech Stack

Backend

.NET Core, REST APIs, Microservices

Frontend

AngularJS, Vue.js

Database

Azure SQL, SQL Server

Azure Compute

IIS (in VMs), App Services / Web Apps, App Service Environment, VMs

Azure Platform

Service Bus, Key Vault, Storage, Log Analytics, Application Insights

Azure Networking

Application Gateway, VNet + NSGs, Load Balancer SNAT, Linux NVA

Identity

Azure AD (now Entra ID), App Registrations

Reporting

Power BI

AWS

Main applications migrated to AWS (parent Sysco standard)

Integrations

Third-party SOAP/WSDL, Outlook add-in

Other

API Gateway, RBAC, Multi-tenancy, Audit logging

What I Help With

Scalable Backend Systems

High-performance APIs and microservices

Complex Integrations

Stripe, Shopify, Microsoft Graph, telecom

AI & Automation

LLM workflows, document processing

Identity & Security

OAuth, Entra ID, Cognito

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