REST API SCIM Provisioning for Scalable Identity Management

The request hit your desk at 3 a.m.: integrate SCIM provisioning with a REST API before the next release. No extensions. No excuses.

REST API SCIM provisioning is how modern systems handle identity management at scale, with full automation. SCIM—System for Cross-domain Identity Management—is an open standard that defines a RESTful API for user and group provisioning. It replaces brittle, custom scripts with predictable endpoints, JSON payloads, and standardized operations.

A solid SCIM REST API exposes endpoints like /Users and /Groups, supporting HTTP verbs such as POST, GET, PATCH, PUT, and DELETE. Onboarding means sending a POST request with compliant schema data. Updates use PATCH with precise attribute changes. Deletions mark the resource inactive or remove it entirely.

SCIM provisioning via REST API is designed to sync identities between IdPs (Identity Providers) and SPs (Service Providers). Instead of manually creating user accounts in every system, SCIM pushes changes from your central directory—Okta, Azure AD, Google Workspace—into all connected apps. The protocol handles mapping, pagination via startIndex and count, and filtering with query parameters like filter=userName eq "alice".

Critical features to implement:

• Schema compliance: Follow IETF draft SCIM specifications to handle core and extension resource types.
• Authentication and security: Use OAuth 2.0 Bearer tokens or signed requests to protect endpoints.
• Error handling: Return proper HTTP status codes, and SCIM-specific error messages in JSON.
• Performance: Support bulk operations to reduce API calls, especially during large migrations.

For engineering, REST API SCIM provisioning means faster onboarding, clean deprovisioning, and fewer failed sync jobs. For compliance, it means traceable, auditable identity events across all systems.

If you want to see SCIM provisioning implemented without the slow ramp-up, go to hoop.dev and see it live in minutes.