TrustedRouter offers a sign-in integration for apps to verify Y Combinator company affiliation through OAuth and verified email domains. Users authenticate with company context including company name, domain, and founding year, with the system checking email verification and funding organization match before granting company-specific benefits.
OWASP cheatsheet covering OAuth 2.0 security best practices, including terminology for clients, authorization servers, resource owners, and resource servers. Describes access tokens, refresh tokens, and Proof of Possession tokens, along with essential security basics like preventing open redirectors and implementing PKCE for CSRF protection.