SHAHAB FAZELI

Delivered full-stack features from design to deployment, collaborating directly with leadership. Integrated third-party services including Stripe usage-based billing with webhooks, Microsoft sign-in via OAuth 2.0, Google Analytics feature tracking, and an HPC (Slurm) compute pipeline. Built Node.js/TypeScript REST APIs with Express, Zod validation, JWT RBAC, rate limiting, and Swagger documentation while keeping backward compatibility. Designed PostgreSQL schemas and migrations on live data and implemented event-driven processing with LISTEN/NOTIFY plus real-time WebSocket updates. Developed React/TypeScript interfaces with Redux Toolkit and RTK Query (dashboards, admin panel, AI chat, Three.js 3D CAD viewer) and shipped an Electron desktop app version. Shipped an in-app AI assistant using LLM tool calling and structured output with validation, integrated with internal APIs. Improved reliability by writing and running tests (Jest, Vitest, Cypress, pytest) and shipping via GitHub Action

Developed core business logic for an ERP used by distribution companies with 100+ customers, including sales, inventory, and accounting using T-SQL stored procedures, triggers, views, and functions. Tuned slow queries and transactions using execution plans, SQL Server Profiler, and indexing strategies, improving performance of key sales and inventory reports by ~25%. Designed normalized 3NF relational schemas to keep data consistent across modules and built reporting queries for sales, inventory, and accounting. Maintained a server-rendered ASP.NET (C#) application, improved ADO.NET data-access code, fixed bugs, and troubleshot issues reported by end users.