GrocerKey — E-Commerce Backend Services

Backend (C# .NET + Microservices)

About

Enterprise-scale microservices backend processing millions of grocery transactions — CQRS architecture with RabbitMQ event queues, ElasticSearch real-time indexing, Redis caching, and multi-tenant support across 10+ retailer configurations.

My Role

Delivered multi-project backend with customer and store APIs, RabbitMQ queue consumers, ElasticSearch sync, cron jobs for store data refresh, and CQRS-pattern domain services. Implemented order modification flows for EBT/credit/gift/tips and user targeting for phased rollouts.

Core Capabilities

• Customer Web API and Store API for catalog, pricing, and checkout
• CQRS pattern with Commands, Queries, and Domain Services
• RabbitMQ event queue consumers for async processing
• ElasticSearch sync for real-time search indexing
• Cron jobs for store sync, picker integration, and data refresh
• Multi-tenant support across different retailer configurations

Architecture

• C# .NET Framework 4.7.2 monolith with ASP.NET Core 2.1 APIs
• Entity Framework 6 + EF Core for data access with SQL Server
• RabbitMQ for event-driven messaging with rate-limited consumers
• ElasticSearch for product search and indexing
• Redis caching with centralized feature flagging

Tech Stack