Ahmed Z.

I’m a software engineer with 5+ years of experience building and maintaining production systems with ASP.NET Core, SvelteKit, TypeScript, WPF, OAuth-based integrations, background processing, secure file workflows, and product-facing infrastructure. I value honest and long-term work relationships with clients, and it is my priority to maintain a healthy workflow and deliver a successful product. My strongest work sits in the places where business software gets tricky: third-party APIs, asynchronous jobs, tenant-aware behavior, document handling, billing or entitlement logic, and codebases that need clearer structure before they become expensive to change. I have worked on systems such as a live Todoist and Google Calendar sync platform, a multi-tenant e-invoice product with encrypted archival and validation flows, and a desktop-and-API automation tool for Evernote. I also integrated a dedicated Javalin service for invoice validation, structured data extraction, and PDF visualization. When a problem repeats across products, I tend to extract reusable infrastructure to reduce duplication and keep future work moving faster. I use SpecKit and Spec-Driven Development as a supporting delivery practice when a project benefits from AI-assisted workflows, clearer requirement breakdowns, or tighter implementation guidance. Core Strengths: • Architecture & Backend: ASP.NET Core - API design - EF Core & Dapper - SQL - Clean Architecture • Operational Engineering: Hangfire - background processing - synchronization workflows - Docker - Linux - CI/CD • Integrations & Auth: OAuth - webhooks - Identity service customization - Google - Todoist - Evernote - Paddle • Security & Platform Work: multi-tenancy - encryption - secure file workflows - reusable package design • Frontend: SvelteKit - TypeScript - better-svelte-emails - SASS - Bootstrap - context/state class design • Desktop: WPF - MVVM - Generic Host - XAML - styling - UI/UX - MVVM Toolkit • Testing: xUnit - integration testing - Testcontainers - Respawn - NSubstitute - FluentAssertions • AI Integration: SpecKit & SDD - Vector Databases - Guard railing - MCP customization I’m a good fit when you need someone who can reason about architecture and delivery at the same time — not just write isolated features, but shape the surrounding system so it stays reliable after launch.