Maid is a Ruby gem and CLI tool for automating filesystem hygiene. Users write declarative rules in Ruby (e.g. `Maid.rules { rule 'old downloads' { trash(dir('~/Downloads/*.iso')) } }`) that select files by glob, age, MIME type, image dimensions, EXIF GPS location, ZIP contents, SHA-1 duplicates, and macOS Spotlight metadata, then act on them with move, rename, trash, copy, remove, mkdir, or rsync sync operations. Safety is a core design point: operations respect a `noop`/dry-run mode, `move` refuses non-directory destinations, renames refuse to overwrite, trashing collides with a timestamped filename, and every action is logged to a rotating `~/.maid/maid.log` (5 × 10 MiB). The CLI (Thor-based, `bin/maid`) exposes `clean` (with `--noop`/`--force`), `daemon`, `logs`, `sample`, and `version` commands. Architecture is a monolithic gem with clear module separation: `Maid::App` (CLI), `Maid::Maid` (engine, defaults, trash path per XDG/macOS), `Maid::Tools` (40+ DSL methods mixed into rule context), `Maid::RuleContainer` (rule registration/following), `Maid::Watch`/`Maid::Repeat` (directory watching via listen, scheduling via rufus-scheduler), `Maid::Platform` (OS detection), and `Maid::Logger` (stdlib Logger wrapper). Rules execute via `instance_exec` against a Maid instance, giving user Ruby code full access to tool methods and helpers like `1.week.since?`. macOS-specific features (Spotlight `mdls`, `tag` labels, download provenance) degrade gracefully on Linux. The gem also ships Rake task helpers (`Maid::Rake::Task`) so file-management rules can be embedded in project Rakefiles. The project is actively maintained: v0.12.0 released 2026-10-17, Ruby 3.3+/3.4 support, security-motivated thor upgrade, and CI across Ubuntu/macOS on multiple Ruby versions. The test suite is substantial (22 spec files, FakeFS isolation, VCR cassettes for geocoder calls, coverage thresholds). Legacy patterns persist: several tools shell out to external binaries (`du`, `mdls`, `rsync`, `tag`, `locate`) and parse raw stdout, a deb-format `ChangeLog` sits alongside `CHANGELOG.md`, `.rubocop_todo.yml` carries 50+ outstanding offenses, and the README's stated Ruby floor (2.7+) is out of sync with the gemspec's enforced `>= 3.3.0`.