Developer, Web Developer, IT​/Tech

Add‑In Developer (Office.js) | Hybrid | London/Sheffield | 10 Month Contract | £500 - £550 inside IR35 | Outlook Add Ins About the Role

We're looking for a seasoned Senior Outlook Add-in Developer to join our team and take ownership of designing, building, and supporting sophisticated Outlook add-ins used in large, enterprise-scale environments.

This role is ideal for someone who thrives in complex messaging ecosystems and has hands‑on experience delivering solutions that work flawlessly across Windows, macOS, web, and mobile Outlook clients, including hybrid Exchange setups spanning on‑premises and Microsoft 365.

• Architect, develop, and support Outlook add-ins using Office.js and modern web technologies
• Ensure add-ins perform consistently across Outlook for Windows, Mac, Web, and Mobile
• Integrate Outlook add-ins with Back End services, APIs, and identity platforms such as Microsoft Graph and Azure
• Focus on performance, security, and reliability in high-volume email scenarios
• Diagnose and resolve issues across multiple Outlook clients and platforms

• Demonstrated experience building Outlook add-ins in enterprise environments
• Strong skills in Office.js, JavaScript/Type Script, HTML, and CSS
• Hands‑on experience with hybrid Exchange (on-prem + Exchange Online)
• Solid understanding of Microsoft 365, Outlook desktop clients, and Outlook Web App behavior

• Experience with Azure services (App Services, Functions, Storage, Key Vault)

If this sounds like you, APPLY NOW!

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