PKCE

API Token Lifecycle: From Issuance to Revocation and Secure Management

The article provides a comprehensive examination of the full API token lifecycle in browser-based applications, emphasizing that signatures alone cannot prevent token theft. It details risks introduced at issuance, storage, transmission, and revocation stages, including improper OAuth grant types and long-lived tokens. Key recommendations include short-lived access tokens, atomic refresh token rotation, and the use of Authorization Code Flow with PKCE for public clients. Storage advice strongly discourages localStorage and sessionStorage in favor of HttpOnly cookies or a Backend-for-Frontend pattern that keeps real tokens on the server. The piece also covers CSRF protections, rate limiting on authorization endpoints, and the advantages of signed client assertions over static secrets. Overall, it stresses that token security depends on the entire lifecycle architecture rather than cryptographic strength alone.

Separating Identity and Delivery Channels for Compliant Telegram Mini App Authentication

A developer shared a detailed case study on building legally compliant user identification for Telegram Mini Apps targeting Russian audiences. Instead of relying solely on Telegram initData verification, the project routes authentication through established Russian providers including VK ID, Yandex ID and MAX. Identity is handled separately from message delivery channels, with telegram_id used only for notifications after account creation. The implementation employs OAuth 2.1 with PKCE for VK, OAuth 2.0 for Yandex, and deep links for MAX while enforcing short-lived cryptographic state values and HttpOnly session cookies. Additional measures include consent checkboxes required by Russian law and polling-based result delivery to support browser, WebView and extension environments. The same architecture was reused for Home Assistant smart-home login, demonstrating reusable separation of identity and channel concerns.

Compliant Telegram Mini App Authentication via Russian ID Providers in My Anti-Social Network Project

The project 'My Anti-Social Network' demonstrates a production-grade approach to Telegram Mini App authorization that meets Russian identification requirements by separating user identity from delivery channels. Instead of relying solely on Telegram initData verification, the system routes authentication through VK ID, Yandex ID, and MAX using OAuth 2.0 / 2.1 flows with PKCE. Sensitive tokens never reach the browser; the client receives only short-lived one-time codes exchanged for HttpOnly session cookies. The architecture supports multiple front-ends including PWA, browser extensions, and Home Assistant integration while maintaining cryptographic protections around state parameters and code verifiers. The solution was implemented for an aggregator delivering personalized news feeds through Telegram, MAX, VK bots, and voice assistants.

OAuth Authorization Server Built Without Storing User Profiles

The article details the evolution of an OAuth Authorization Server that deliberately avoids storing user profiles, relying instead on external identity providers for authentication. It addresses three core constraints: hundreds of dynamically created isolated APIs, a public SPA client without a BFF, and the inability of resources to query the AS on every request. The design separates concerns so the AS handles only clients, tenants, grants, audiences, scopes, keys, sessions, and token issuance while the Main API owns profiles and roles. Tokens are managed securely inside a Service Worker using a custom FedCM grant, eliminating races across tabs and reducing XSS exposure. The approach minimizes blast radius, simplifies compliance, and keeps the AS replaceable without affecting product domain logic.