moderate is a complete Trust & Safety system and content moderation engine for Ruby on Rails apps. Trust & Safety (T&S) is the system within an app that lets users report abusive content, block each other, filter objectionable text and images before they're posted (profanity, bad words, NSFW/nudity, etc.), and run a moderation queue your admins actually use. It also allows you to easily plug in automated AI moderation systems like OpenAI Moderation or AWS Rekognition to quickly filter, flag and/or automatically block harmful content (text or image). Any app with user-generated content (UGC) needs this: social apps, marketplaces, dating, communities, forums, comments, reviews, chat, etc. The moderate gem bundles the four things every UGC app needs behind one data model and one set of hooks: abuse reporting (report posts, comments, profiles, listings, messages, and other users), bidirectional user blocking behind a single enforced source of truth, pre-publication content filtering for profanity, slurs, hate, spam, harassment, and objectionable or NSFW text and images in off/block/flag modes, and an audited moderation queue with locked resolve/dismiss/remove-content/ban decisions, internal appeals, and statement-of-reasons notifications. Filtering uses a tiny classify(value) => Result adapter contract: a fast, offline, multilingual wordlist/profanity/bad-word blocklist ships as the zero-dependency default, and you bring your own classifier (OpenAI omni-moderation, AWS Rekognition image/NSFW detection, Google Perspective, or self-hosted) as an optional reference adapter, not a forced dependency. moderate also ships primitives aligned with the EU Digital Services Act (DSA notice-and-action, statement of reasons, appeals, transparency) and with the Apple App Store (Guideline 1.2) and Google Play user-generated-content review rules that get apps rejected without report/block/filter. It is a mountable, UI-agnostic Rails engine with no hard dependencies beyond normal Rails stuff.