The relevant terms of art are SAML, SCIM, SSO. There are several providers - Okta, AWS, and more. Fair warning: expect to pay enterprise tax on all your SaaS

The relevant terms of art are SAML, SCIM, SSO. There are several providers - Okta, AWS, and more. Fair warning: expect to pay enterprise tax on all your SaaS plans for the pleasure of allowing you to do SSO!