Monbooru is a private, tag-based gallery for your own image, video, and manga collection, searchable the way booru sites are, but hosted entirely on your server. Drop files into watched folders and they appear within seconds, with browser uploads, SHA-256 deduplication, and an inbox where new arrivals wait until you have reviewed and tagged them. Local auto-tagging runs ONNX models such as WD14, JoyTag, Camie, and PixAI on CPU or GPU, so a collection gets searchable labels without sending a single image to a cloud service. Tag management covers merges, aliases, implications, and custom categories, while rating tags with an SFW ceiling keep sensitive material hidden until you choose otherwise. Search combines wildcards, OR terms, and exclusions with filters for folder, date, size, dimensions, and AI generation settings, and saved searches keep favorite queries one click away. Batch actions retag, move, delete, or auto-tag whole selections at once, and the built-in manga reader opens CBZ and ZIP archives as single items. Image pages record sources, artist commentary, and your own notes, and near-duplicate detection lines up lookalikes side by side for cleanup. Multiple galleries can live in one instance, each with its own folders and database, and an optional password plus scoped REST API tokens control who and what can connect. Running on a dedicated VPS on RepoCloud with guaranteed CPU, RAM, and SSD, full root SSH access, and a browser serial console. AGPL-3.0 licensed.