Nadeem Ashfaq

Senior full-stack developer

Fiverr • Freiberufler

Aug 2022 - Present • 4 yrs 2 mos

Expert in full-stack development, Office/Google Add-ins, APIs, and enterprise solutions.

Senior Full-Stack Developer | Office.js, SharePoint & Microsoft 365 Add-ins

Xfinitive

Feb 2025 - Aug 2026 • 1 yr 6 mos

Worked as a Senior Full-Stack Developer specializing in Microsoft 365, Office.js, SharePoint, and enterprise web applications. Designed and developed production-ready solutions integrating Office Add-ins with Microsoft 365 services, SharePoint Online, Microsoft Graph API, and Entra ID. Key responsibilities included architecting scalable full-stack applications, developing custom Office Add-ins for Word, Excel, Outlook, and PowerPoint, implementing Microsoft 365 authentication and SSO using MSAL, and integrating SharePoint data and services through Microsoft Graph and REST APIs. Built modern web applications using React, Next.js, TypeScript, Node.js, .NET, PostgreSQL, and Supabase, while focusing on clean architecture, security, performance, and maintainability. Worked closely with clients and stakeholders to translate business requirements into reliable technical solutions and delivered end-to-end features from architecture and development through deployment and production support. Core areas: * Office.js and Microsoft 365 Office Add-in development * SharePoint Online and SharePoint Framework (SPFx) * Microsoft Graph API and Microsoft Entra ID * MSAL authentication and Microsoft 365 SSO * React, Next.js, TypeScript, Node.js and .NET * REST API and third-party service integrations * PostgreSQL, Supabase and cloud-based applications * Enterprise application architecture and technical solution design * Performance, security and production-ready development