What This Is
We build custom integrations with Microsoft 365 through Microsoft Graph API, a single endpoint that connects your application to Outlook email, Calendar, Teams, SharePoint, OneDrive, Azure AD user management, and the rest of the Microsoft 365 suite. Instead of building separate integrations for each Microsoft service, Graph provides unified access.
Microsoft Graph API is the gateway to Microsoft’s entire cloud ecosystem. We build integrations that send and read emails through Outlook, manage calendar events, post messages to Teams channels, access SharePoint document libraries, sync user directories from Azure AD, and automate administrative tasks. The integration handles the complexity of Microsoft’s OAuth2 flow, delegated vs application permissions, and the Graph API’s specific pagination and batching patterns.
These integrations are built with the same service layer architecture we use across all API work. Each one abstracts Microsoft’s API behind your business logic, handles the authentication lifecycle, and processes events through queue jobs for reliability.
When You Need This
Microsoft 365 API integration makes sense when your organisation runs on Microsoft’s ecosystem and your application needs to interact with that data programmatically. Common scenarios:
- You need to send or read email from your application through Outlook rather than a generic SMTP service
- Calendar management: creating, updating, or reading calendar events from your application for scheduling features
- Teams integration: posting notifications, creating channels, or building bots for your Microsoft Teams workspace
- SharePoint document access: reading or writing files in SharePoint libraries from your application
- User provisioning: syncing Azure AD user directories with your application’s user management
- Single sign-on: authenticating users in your application via their Microsoft 365 accounts
How We Work
Microsoft 365 projects start with permission scoping: identifying exactly which Microsoft Graph permissions your integration needs and whether they require delegated (user-context) or application (daemon) access. Over-permissioning is a security risk; we request the minimum scopes necessary.
We implement Azure AD OAuth2 authentication with automatic token management, including refresh token handling and multi-tenant support where needed. The authentication layer handles the differences between delegated flows (user signs in) and client credential flows (application accesses data without a user present).
The Graph API service layer manages request batching (up to 20 requests per batch), pagination for large result sets, and change notifications (webhooks) for real-time event processing. Each Microsoft service your integration touches gets its own handler with appropriate error handling and retry logic.
What You Get
- Email integration: send, read, and manage Outlook email programmatically from your application
- Calendar management: create, update, and query calendar events with attendee management and scheduling
- Teams messaging: post notifications, create channels, and build conversational bots for Teams
- SharePoint access: read and write documents in SharePoint libraries with metadata management
- User directory sync: Azure AD user and group data synchronised with your application
- Single sign-on: Microsoft 365 authentication as a login option for your application users
- Change notifications: real-time webhooks for email, calendar, and user changes
Technologies We Use
- Microsoft Graph API: unified endpoint for Outlook, Calendar, Teams, SharePoint, OneDrive, and Azure AD
- Azure AD: OAuth2 authentication with delegated and application permission models
- Laravel: service layer with token management, request batching, and webhook processing
- PostgreSQL: sync state tracking, token storage, and cached directory data
Related Systems
Microsoft 365 integration connects your communication and document infrastructure to operational systems: a CRM syncing email history from Outlook, a booking system managing Calendar availability, or an admin system provisioning users through Azure AD. For team messaging integration outside Teams, Slack API Integration follows the same patterns. For organisations on Google’s ecosystem rather than Microsoft’s, see Google Workspace API Integration. All of this is part of our API Integrations practice.
Talk to Us About Microsoft 365 Integration
If your application needs to work with Microsoft 365 data rather than treating it as a separate ecosystem, get in touch and we will scope the Graph API integration.
