Nat Sakimura
- Co-author of OpenID Connect Core 1.0
- Co-author of FAPI (Financial-grade API) specifications
Bio
Nat Sakimura has chaired the OpenID Foundation for many years and is a primary author of the OpenID Connect specifications and the FAPI security profile used by open banking implementations worldwide.
Profile built from public OpenID Foundation and IETF records.
Where their work shows up
Sakimura's authorship runs through OpenID Connect and the FAPI security profile, which became the de facto baseline for open banking worldwide and, through PSD2, for European payment authentication. FAPI is the best available template for any high-value API, not just financial ones.
Podcasts
Related on Start with Identity
- PodcastAuth0
The late Vittorio Bertocci's interviews with the authors of OAuth, OpenID Connect, FIDO, and SAML. Ended in 2022, and still the best audio archive on identity s
- CVEKeycloak client policy enforcement flaw
A 2026 Keycloak client-policy enforcement bug. Client policies are how you ban implicit flow, require PKCE, or force FAPI. If they do not fire, the realm's writ
- GlossaryOAuth 2.0
OAuth 2.0 is the standard authorization framework for delegated access. It lets a client obtain limited access to a resource owner's data without handling their
- GlossaryPAR
Pushed Authorization Requests (RFC 9126). The client sends authorization parameters directly to the server over a back channel first, hardening the flow against
- GlossaryRich Authorization Requests (RAR)
OAuth 2.0 Rich Authorization Requests (RAR, [RFC 9396](https://www.rfc-editor.org/rfc/rfc9396), Proposed Standard, May 2023) add an `authorization_details` para
- ExpertCo-author of TLS 1.0 and the W3C DID specification
Christopher Allen co-authored the IETF TLS 1.0 specification, co-authored the W3C Decentralized Identifiers specification, and in 2016 published The Path to Sel