User Switching is a mature WordPress plugin providing instant switching between user accounts. The plugin allows administrators to switch to any user account from the Users screen, switch back to their original account, and 'switch off' (temporarily log out while retaining the ability to switch back). It integrates deeply with WordPress core authentication, using cookies to track originating users and session tokens to manage state. The code is entirely contained in a single main file (`user-switching.php`) that implements a singleton class with hooks and filters. It includes comprehensive integration tests (PHPUnit) and acceptance tests (Playwright) covering switching flows, capabilities, session handling, and command palette features. The plugin also provides explicit integration points for WooCommerce, BuddyPress, bbPress, and the WordPress REST API and command palette. The architecture is typical of a well-crafted WordPress plugin: event-driven via hooks, with clear separation between utility functions and the main class. It is not a library or framework but a self-contained plugin that can be dropped into any WordPress site meeting its requirements.
Hanko is a production-grade, self-hostable authentication and identity platform written primarily in Go. The backend exposes public, admin, and management HTTP APIs plus a CLI for migrations, user import/export, JWK/JWT management, and config schema generation. Authentication is implemented as a custom state-machine engine (flowpilot) driving login, registration, password/passkey/MFA/third-party OAuth/SAML flows, backed by JWT sessions, device trust, webhooks, audit logs, and rate limiting. The persistence layer uses gobuffalo/pop with a broad set of per-entity persister interfaces and roughly 65 Fizz migrations covering users, emails, credentials, sessions, tenants, organizations, roles, SAML providers, and webhooks. The frontend is split into a TypeScript SDK (`@teamhanko/hanko-frontend-sdk`) and Preact-based web components (`@teamhanko/hanko-elements`) that render flow states into embeddable `<hanko-auth>` and `<hanko-profile>` elements. The repository also contains a quickstart Go server, framework examples for React, Vue, Angular, Next.js, and Express, Playwright e2e tests, Docker Compose stacks, and Kubernetes manifests. Data flows through Echo routers into flowpilot actions/hooks, which validate inputs, persist state, issue sessions, and trigger webhook events; PostgreSQL, Redis, SMTP, and external OAuth/SAML providers are the primary external dependencies. Overall the codebase is well-structured and heavily tested, with sophisticated security handling around redirect validation, account linking, multi-tenant isolation, and webhook signing. The main friction points are the custom flowpilot framework's learning curve, a very large configuration surface, duplicated example code, and some stale example/e2e toolchains relative to the core Go and Node versions.
GoTrue is a self-contained user registration and authentication API written in Go. It provides endpoints for signup, login (via email/password or OAuth2 providers like GitHub, GitLab, Google, Bitbucket, Facebook), token refresh, password recovery, email verification, and user management (CRUD for admin users). The architecture is a monolithic HTTP API using the chi router, backed by a MySQL database (via pop/v5 ORM) and a configurable mailer (SMTP or noop). It supports both single-tenant and multi-tenant deployments, with JWT-based authentication (HS256) and optional SAML SSO. The codebase is well-organized into packages: api for HTTP handlers, models for database entities, conf for configuration, mailer for email sending, and crypto for security utilities. It includes extensive unit tests and integration tests using a MySQL test database.