Mac Sai

Mac Sai is a free, open-source Mac maintenance utility from the Mac Sai contributors, hosted by iliyami. It combines file cleanup, disk-space analysis, application management, a curated malware-pattern scanner and a menu-bar system monitor. It is intended for Mac users who want to inspect storage and maintenance results before acting, rather than a subscription-based managed security service.

Inspection and cleanup

Smart Scan groups cleanup, protection and performance checks. System Junk and Mail Attachments inspect caches and other selected categories, while Space Lens visualizes disk usage and Large & Old Files identifies candidates by size and age. The duplicate finder uses progressive hashing and inode checks; its APFS consolidation mode is distinct from deleting copies. The uninstaller locates associated files, and Reset to Defaults removes selected app settings and caches while preserving the app itself. Login-item management and maintenance tasks can change system behavior; review the selected task and its impact.

The malware module checks curated signatures and known patterns at different scan depths. The project explicitly distinguishes it from a full antivirus product. A clean result does not guarantee that the Mac is malware-free, and Apple notarization is not a guarantee against all harmful behavior. Privacy cleanup can remove browser history, cookies and caches, which may sign you out or remove useful local state. Permissions Overview is read-only and links to System Settings rather than independently granting privacy permissions.

The menu-bar helper is a separate process that can launch at login and show CPU, memory, disk, battery and network information. Its recommendations do not require accepting every proposed cleanup. Scan results, logs and filenames can reveal private information; handle them accordingly.

Mac installation and access

Install the mac-sai Homebrew Cask or open the official DMG and drag Mac Sai to Applications. Official HEAD and GitHub release metadata confirm 14,279,425 bytes for the recorded 1.21.3 DMG. This is download size, not installed storage or the space reclaimed by any scan. The official release and Cask require macOS 14 Sonoma or later. This is a Mac utility; no Windows or Linux application package is established by the project.

The official build script defaults to a universal arm64 and x86_64 build for the app and menu helper. This describes the project's build configuration rather than an independent inspection of every released DMG. The recorded Cask declares no extra package dependency or explicit conflict. Building from source requires Swift 6 and the project's development toolchain; ordinary DMG users do not need to compile it.

Full Disk Access is needed for complete results in protected locations, including relevant Mail, Privacy and Malware scans. The official instructions ask you to add Mac Sai in System Settings and restart it. Grant this broad access only if you intend to use those scans. Some maintenance tasks require administrator authorization. The project documents Trash-first deletion and protected-path safeguards, but permanent deletion, Trash emptying and Shredder modes have different consequences. Keep independent backups and review selected files; secure overwrite is not a guarantee of physical erasure on SSDs, snapshots or remote copies. Universal-binary thinning rewrites application binaries and can affect compatibility or signatures, so treat it as a deliberate modification rather than ordinary cache removal.

Cost, license and network use

Mac Sai is BSD-3-Clause licensed and free without a subscription, in-app purchase or paid Pro tier. No Mac Sai account or cloud activation is documented for ordinary local use. The project states that it does not include telemetry or analytics. This does not make all activity offline: downloading releases and checking installed applications' Sparkle feeds can involve network requests. Third-party applications and services retain their own accounts and licenses. Keep system and file-management decisions under your control rather than interpreting safety mechanisms as a promise that no data can ever be lost.

Official sources: https://github.com/iliyami/MacSai/tree/v1.21.3 ; https://github.com/iliyami/MacSai/releases/tag/v1.21.3 ; https://github.com/iliyami/MacSai/blob/v1.21.3/LICENSE