Abubakr Eldaw

Gave 250+ restaurant brands near-real-time sales insight. Reports that previously ran against live transaction tables — timing out and causing lock contention on the production database — now return a full year of data in under ~100ms. A standalone .NET engine pre-aggregates the full tenant base (338K+ workdays, 205M+ transaction line-items) into purpose-built summary tables, moving analytical load off the transactional path so reporting no longer competes with order-taking. Incremental, trigger-driven resync keeps every tenant current.

Enabled the company to take online payments and onboard new providers without a rebuild, on a design built for money-correctness. Provider-agnostic, and engineered for the ways payments fail in practice — concurrent operations, timeouts, disputes, and out-of-order events — resolved by background reconciliation against the provider, a full audit trail, and database-level guarantees so partial failures can't silently corrupt money.

The tool call-center agents use to take orders across multiple restaurant brands from one screen — now handling 450K+ orders across multiple brands, replacing an older system. Angular + .NET backend-for-frontend that keeps auth tokens server-side so they never reach the browser, multi-company sessions with PIN-based employee identity, real-time updates, and full EN/AR RTL support.

A customer-facing ordering app where one codebase serves many restaurants, each with its own branding and menu. Angular + .NET backend-for-frontend, a complete payment flow (card save/verification, Apple Pay, refunds), and a customer dispute-to-refund loop wired into the payment reconciliation flow.

Kept the core database fast as invoice volume grew by moving e-invoice storage out of SQL Server into AWS S3 — migrating tens of millions of existing e-invoices to object storage and taking heavy invoice blobs off the transactional path.