Coral is an open-source, multi-tenant comment moderation platform developed by Vox Media. It provides a full-stack application with embedded commenting widgets (stream), a comprehensive admin panel for moderation, configuration, and community management, an authentication system supporting local, OAuth2/OIDC, Google, Facebook, SSO, and account management pages. The system architecture consists of a Node.js/Express server with Apollo GraphQL, MongoDB for persistence, Redis for caching and pub/sub, and Bull for job queues. The client uses React with Relay for GraphQL data fetching, and is organized into several bundles: stream (the embeddable comment widget), admin, auth, account, install, count, and embed. The core data flow involves comments being submitted via GraphQL mutations, processed through a modular pipeline (spam detection, word list filtering, toxicity analysis via Perspective API, external moderation phases, and pre-moderation rules), stored in MongoDB, and then distributed via GraphQL subscriptions and notifications (email, Slack, webhooks). The codebase is extensive and well-tested, though it exhibits some legacy patterns (recompose HOCs, partial migration from class components to hooks, duplicated utility code between client and server scripts).