DockDoor Brings Back the Window Peeking You Miss From Windows

If you've ever hovered over a Dock icon on macOS with six windows open and thought, "which one is which?"—you're not alone. Apple's Dock is iconic, but it doesn't give you much context when you've got a pile of windows stacked behind a single icon. DockDoor is an open-source project that fixes that, bringing Windows-style window peeking and Alt+Tab switching to macOS.

What It Does

DockDoor reintroduces the "Window Peeking" functionality that Windows and Linux users have taken for granted for years. The idea is simple: hover over a Dock icon, and you get a visual preview of every open window for that application. From there, you can see what's open, manage it, and switch between windows without the usual guesswork.

It also includes an Alt+Tab-style window switcher (a nod to Windows muscle memory) and enhancements to the native Cmd+Tab behavior. The project is written in Swift, built with Xcode, and designed to feel like a native extension of macOS rather than a bolted-on utility. The README describes it as fast, lightweight, and seamlessly integrated—which is the bar any Dock-adjacent tool has to clear to be worth keeping around.

Beyond the core previews, DockDoor supports multiple preview layouts and window switcher layouts, so you can shape the experience to something that fits how you actually work. There's also Dock Locking, which lets you pin the Dock to a specific monitor in multi-monitor setups—a small feature that anyone juggling three displays will appreciate.

Why It's Cool

Here's what makes DockDoor worth a look:

• It fills a real gap, not an invented one. macOS has never shipped window peeking, and the community has been patching around it with third-party tools for years. DockDoor takes a focused swing at that specific problem instead of trying to be a whole window-management suite.

• The free version has no paywall, and the README is refreshingly direct about it. "DockDoor Free has no paywall and never will. Every feature in this repo is free, forever." That's an unusually clear commitment, and it means you can evaluate the project without wondering where the upsell is hiding.

• The Pro model is honest. Rather than gating features that already exist in the free app, DockDoor Pro is a separate paid application from the same developer. It replaces the macOS Dock entirely and adds things like live window previews with 20+ actions, spring magnification at your display's full refresh rate, folder fan-out, a drag-and-drop file tray with AirDrop, and a widget marketplace. It's $20 one-time for three Macs, no subscription. You don't need it to use DockDoor, but it's a legitimate way to support the free project if you like it.

• Layout flexibility. The README shows off multiple dock preview layouts and window switcher layouts. That's the kind of detail that separates a tool you tolerate from one you configure once and forget about, because it actually matches your workflow.

• Dock Locking for multi-monitor setups. Locking the Dock to a specific monitor sounds minor until you've had it jump to the wrong screen mid-task. It's a small quality-of-life feature that signals the developer actually uses their own software.

• Privacy is part of the pitch. The tagline explicitly says it "respects your privacy," which matters for a utility that reads your window contents to generate previews. It's open-source, so you can verify that claim rather than take it on faith.

How to Try It

Getting started is straightforward:

1. Head to the DockDoor repository on GitHub.
2. Grab the latest release directly from the download link.
3. Open the DMG and install the app as you would any macOS application.
4. Grant the permissions macOS will ask for—window peeking requires accessibility access, and the app will guide you through it.
5. Hover over a Dock icon with multiple windows open and see the previews in action.

If you want to dig deeper into features and documentation, the README points to dockdoor.net. And if you're curious about the paid option, pro.dockdoor.net has the details on what the Pro app adds.

Since it's open-source, you can also build it yourself if you'd rather not download a prebuilt binary—it's a Swift/Xcode project, so the toolchain is standard for macOS development.

Final Thoughts

DockDoor is best suited for anyone who's spent years on Windows or Linux and keeps reaching for a feature macOS doesn't have, or for macOS users who simply want more context from their Dock. It's a focused utility solving a specific, well-understood problem, and the free-forever commitment makes it an easy recommendation to try. If you find yourself relying on it, the Pro app is a reasonable way to give something back. Either way, it's a good example of open-source filling a gap that a platform vendor has left open for far too long.

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