Affirm is seeking a hands-on CIAM backend engineer to design and ship core identity services for B2C and B2B platforms. You will build backend systems in Python and Kotlin, integrating OAuth 2.0, OIDC, SAML, and SCIM with scalable, secure APIs. Lead end-to-end authentication flows, MFA, device binding, and adaptive challenges while automating infrastructure with IaC and CI/CD pipelines. This remote-first role offers strong health advantages and equity.