Kudu is an open-source system maintenance tool under the MIT licence, built for Windows, macOS and Linux, and it puts junk cleanup, startup entries, software updates and privacy switches behind one window. The cleanup rules cover 168 applications and 15 browsers; every run is previewed first and leaves a receipt behind.

Install it once and the chores have a door

Three symptoms turn up on any machine after a couple of years: a system drive that goes red for no visible reason, a login that takes a moment too long, and pop-ups in the corner several times a day. The tools that answer them usually sit in four or five separate programs, one for junk, one for startup, one for drivers, one that only uninstalls. Kudu's idea is plain: gather them into one window, a navigation column on the left, the job at hand on the right.

It runs on Windows, macOS and Linux, with installers for Windows 10 and 11 on x64 and ARM64, macOS 12 or newer, and AppImage and deb packages for Linux. The desktop application is MIT-licensed, needs no account, carries no ad banner and no trial clock. The project's own figures are 5.5 million downloads, 4.2k stars on GitHub, and an interface translated into 30 languages.

Before it deletes anything, you see the list

The cleaner's rule library covers 168 applications and 15 browsers, drawing on browser caches, crash dumps and shader caches. Clients that arrived in the last two years are there as well: long-running programs such as Claude and Cursor get their own entries for working directories. Nothing about the rules is opaque. Each one is a JSON file in the repository that can be read and changed, so adding a cleanup path for some application is a pull request rather than a support ticket.

What separates it from a single-button slimming tool is what happens on either side of the run. Beforehand, every line in the list can be unticked, and folders marked as excluded never enter the candidates. Afterwards the receipt breaks the run into numbers: items selected, items it tried to delete, items actually deleted, items skipped and items that failed, plus a line about logical space freed that reminds you logical size is not the same as extra room on the disk.

The small print in the receipt is worth reading. A skipped item usually comes with a reason, a file in use or a permission problem, and understanding it saves the same mistake on the next run.

Where the space went, and when

The disk analyser gives a cross-section of right now, a treemap laid out by area so the heaviest folder is obvious. Storage history supplies the other half: point it at a folder, let it take snapshots at intervals, and the curve shows the day that folder started to swell. Snapshots store only names, sizes and path metadata, never file contents, are kept for 90 days by default, and are capped at 250 MB.

Privacy switches, updates and startup items each get a page

Privacy hardening lists 57 Windows settings and 33 macOS settings in one column, from advertising identifiers and diagnostic data to newer features such as Copilot and Recall. The premise is that anything can be changed back: each entry states its current value and what changing it does, and a restore centre keeps a record so the original state can be brought back.

Updates go through whatever package manager the system already has, winget on Windows, Homebrew on macOS, apt, dnf or pacman on Linux, with drivers in a column of their own and unwanted updates hidden for now. The startup manager sorts by impact rather than alphabetically, so whatever is slowing the login is visible at a glance. Game mode follows another logic: it applies 18 game-related tweaks at once and puts all of them back when you exit.

Who it suits, and who it does not

For anyone who just wants the machine to stop stuttering and stop filling up, what Kudu removes is the work of carrying judgements between tools: cleanup has a preview, changes leave a record, a wrong move has a way back. For anyone who prefers doing it by hand, the command line interface emits JSON, can feed Prometheus, and can be dropped into a scheduled job.

The boundaries deserve a sentence. The desktop side is free; the cloud part is a per-device subscription for multi-machine monitoring, alerts and remote execution, which a single machine does not need and which leaves local features untouched. Maintenance tools also carry risk by nature: no deep clean belongs on a machine without a backup, however carefully the software is written.

If clicking through all of it is too much, the scheduler chains the actions into a flow and starts it only when conditions are met, an idle machine, mains power, or a time window of your choosing, stepping aside while a game is running. That is a good deal more useful than cleaning whenever you happen to remember.

Version 3.13 is a small step: three of its four fixes concern macOS firewall state detection, Windows disk throughput sampling and a problem that surfaced when winget upgrades were discovered, the kind of fault you meet only after months of use. What keeps people around is still the habit of laying every step out in the open.