mcopy

Fast, queue-aware file and folder copying built around the native right-click workflow, on Windows, macOS and Linux.

mcopy makes large copy operations feel lighter and more controlled. Instead of forcing a terminal-first flow, it turns the familiar copy/paste gesture in your file manager into an async pipeline with a live progress window, cooperative pause/resume/cancel controls, and a clean separation between shell integration, copy state, copy orchestration, and UI.

Contents

• What mcopy Is
• Install
• Using It
• Commands
• How It Works
• Permissions
• Architecture
• Development
• Publishing to package registries
• Upgrading from 0.2
• Troubleshooting
• Limitations

What mcopy Is

A Rust copy tool focused on three things:

• A file-manager-native copy/paste experience
• Async, concurrent file copying
• Visibility and control during long-running operations

The flow is:

1. Select files or folders.
2. Choose Copy with mcopy.
3. Navigate to the destination.
4. Choose Paste with mcopy.
5. Watch and control the operation in a dedicated progress window.

The Paste entry only appears once something has actually been copied, and disappears again as soon as the paste completes.

Install

Download the artifact for your platform from the latest release and run it. Once installation finishes, the downloaded file is no longer needed — you can delete it, eject the disk image, or remove the package file, and mcopy will keep working.

Windows

Run mcopy-setup-<version>-x86_64.exe.

Installs per-user into %LOCALAPPDATA%\Programs\mcopy, adds a Start menu entry, and registers itself in Settings ▸ Apps for normal removal. No administrator rights are required at any point. The installer offers to add the right-click entries; you can also add them later from the app.

The installer is unsigned, so SmartScreen will warn on first run. Choose More info ▸ Run anyway.

macOS

Open mcopy-<version>.dmg and drag mcopy to Applications, or run mcopy-<version>.pkg for a guided install.

The build is unsigned and un-notarized, so Gatekeeper will refuse the first launch. Right-click the app and choose Open, then confirm. To remove mcopy, drag it to the Trash — run mcopy shell-uninstall first if you want the Finder Services removed too.

Linux

On Debian and Ubuntu:

sudo apt install ./mcopy_<version>_amd64.deb

On other distributions, use the portable tarball:

tar xzf mcopy-<version>-x86_64.tar.gz
cd mcopy-<version>
./install.sh                 # installs into ~/.local, no root needed

Then launch mcopy once and press Install to add the file-manager entries for your account. Removal is sudo apt remove mcopy or ./uninstall.sh.

Nautilus (GNOME) and Dolphin (KDE) are supported. Thunar is not — see Limitations.

Building from source

cargo build --release

On Linux you will need the development packages gpui links against:

sudo apt install libx11-dev libxcb1-dev libxkbcommon-dev libxkbcommon-x11-dev \
                 libwayland-dev libfontconfig1-dev libfreetype6-dev \
                 libvulkan-dev libssl-dev pkg-config

Using It

Select files or folders, right-click, and choose Copy with mcopy. Multi-item selections are supported: the file manager invokes the verb once per item, and mcopy stitches them into a single copy session.

Navigate to the destination, right-click, and choose Paste with mcopy. A progress window opens showing the current file, an overall counter, and Pause and Cancel controls. It appears in the taskbar, Dock or window switcher, so you can minimize it and come back to it during a long copy.

When the copy finishes cleanly the window closes itself. If any items failed it stays open and names the reason.

Commands

mcopy is usable from a terminal as well as from the file manager.

Command	Purpose
mcopy	Open the setup window
mcopy shell-install	Register the file-manager entries for the current user
mcopy shell-uninstall	Remove them
mcopy shell-uninstall --all-users	Also remove machine-wide entries left by 0.2 (Windows; needs admin)
mcopy copy <paths…>	Copy paths into the mcopy clipboard
mcopy copy --append <paths…>	Add to the current copy session
mcopy paste <target>	Paste the copied items into target
mcopy status	Show what is currently copied
mcopy clear	Forget the copied items
mcopy <src> <dst>	Direct terminal copy with progress bars

install and uninstall remain as aliases for shell-install and shell-uninstall.

Terminal-copy options: -j/--concurrency <n> to override the worker count, and --no-progress to suppress the progress bars.

How It Works

1. Copy canonicalizes the selection and records it as a copy session.
2. The Paste entries in the file manager become visible.
3. Paste validates the destination, then expands the selection into a flat copy plan.
4. Destination directories are created up front.
5. The progress window opens and the queue runs concurrently.
6. On success the copy session is consumed and the Paste entries hide again.

Copy state

The copy session is a single record in a private per-user directory, written atomically. It is the source of truth; the system clipboard is written too, but only for interoperability. That split matters on Linux, where the X11/Wayland selection belongs to a live process and would vanish the moment the short-lived copy command exits.

The session is validated every time it is read, so sources deleted since the copy are dropped automatically — and if none survive, the Paste entries hide.

A session is consumed only by a paste that fully succeeds. Cancelled, failed and partially failed pastes keep it, so you can simply try again.

Concurrent pastes are prevented by a lock: a second paste started while one is running is refused rather than allowed to race into the same folder.

Concurrency

Default is CPU cores × 4, clamped to between 4 and 128.

Permissions

mcopy never requires administrator or root rights for normal operation.

Shell integration is per-user everywhere: HKEY_CURRENT_USER\Software\Classes on Windows, ~/Library/Services on macOS, and ~/.local/share on Linux. The one exception is shell-uninstall --all-users, which exists purely to clean up the machine-wide entries that mcopy 0.2 created and which does need elevation.

If a copy hits a permission problem, the progress window names it and suggests a next step, rather than reporting an anonymous failure count. On macOS a denial in ~/Desktop, ~/Documents or ~/Downloads is usually a privacy (TCC) restriction, and the window says so.

Logging

mcopy writes a log to:

Platform	Location
Windows	%LOCALAPPDATA%\mcopy\logs\mcopy.log
macOS	~/Library/Logs/mcopy/mcopy.log
Linux	$XDG_STATE_HOME/mcopy/mcopy.log (usually ~/.local/state)

Set MCOPY_LOG to debug, info, warn, error or off. It records filesystem paths and error kinds; it never records file contents or clipboard payloads.

Architecture

src/
├── main.rs              command routing; owns the Tokio runtime
├── lib.rs               public surface
├── cli/                 argument parsing and command implementations
├── clipboard/
│   ├── mod.rs           copy/paste API and the system-clipboard mirror
│   └── state.rs         the owned copy-state model, lock, and on-disk format
├── copy/
│   ├── mod.rs           the concurrent copy engine
│   ├── controller.rs    cooperative pause / resume / cancel
│   ├── error.rs         failure classification
│   ├── progress.rs      progress event types
│   └── walk.rs          directory traversal and copy planning
├── platform/
│   ├── mod.rs           the ContextMenu trait — the single #[cfg] seam
│   ├── location.rs      is this executable somewhere durable?
│   ├── windows.rs       Explorer verbs (HKCU)
│   ├── macos.rs         Finder Services
│   └── linux.rs         Nautilus scripts and Dolphin service menus
├── ui/
│   ├── theme.rs         light/dark palettes
│   ├── widgets.rs       shared elements, including the logo
│   ├── shutdown.rs      the single shutdown path
│   ├── install/         the setup window
│   ├── progress/        the copy progress window
│   └── notice.rs        one-message window
└── util/                paths, shell escaping, logging, safe output

Platform differences live behind the ContextMenu trait, selected in exactly one place in platform/mod.rs. Nothing else in the codebase branches on the OS.

Project identity

Every installer, package and registry manifest has to agree on who publishes mcopy and what it is called. Those values are declared once and read by everything else:

Value	Declared in
App id io.github.nakamoz.mcopy	mcopy::APP_ID in src/lib.rs
Publisher NAKAMOZ	mcopy::APP_PUBLISHER
Copyright	mcopy::APP_COPYRIGHT
Version, description, homepage, license, author	Cargo.toml [package]

scripts/identity.sh and scripts/Identity.ps1 parse those two files, and every packaging script sources one of them. build.rs carries its own copy of the publisher and copyright (a build script cannot depend on the crate it builds) and exports what it embedded, which a unit test in src/lib.rs asserts against the constants — so the shipped binary's File Properties can never disagree with the .deb, the .pkg or the winget manifest.

The app id is load-bearing rather than decorative. It is simultaneously the macOS CFBundleIdentifier and installer package id, the Wayland/X11 app_id, the .desktop file's name, the AppStream component id, and the Finder Services bundle prefix. A mismatch between any two shows up as a window with no icon or an application a software centre cannot attribute.

Publishing to package registries

The release workflow produces the installers; the registry manifests are generated next to them so their checksums always match the artifact being described.

Winget — after publishing the GitHub release:

.\scripts\package-windows.ps1        # produces dist\mcopy-setup-<version>-x86_64.exe
.\scripts\package-winget.ps1         # produces dist\winget\manifests\...
winget validate --manifest dist\winget\manifests\n\NAKAMOZ\mcopy\<version>

Copy that directory into a fork of microsoft/winget-pkgs and open a pull request. The InstallerUrl must already resolve, so publish the release first.

Homebrew — scripts/package-macos.sh writes dist/mcopy.rb alongside the disk image, with that image's SHA256 already filled in:

brew audit --cask --new --online dist/mcopy.rb

Submit it to homebrew-cask, or host it in a personal tap.

Linux distributions — the .deb carries a proper Maintainer, Homepage and dependency list derived from the linked binary, and installs an AppStream component so GNOME Software and KDE Discover show the developer, description and license. scripts/package-linux.sh validates both the AppStream metadata and the desktop entry when appstreamcli and desktop-file-validate are available; CI installs them so validation always runs there.

Tech stack

Rust 2024 · Tokio · Futures · Clap · Indicatif · GPUI · arboard · dirs

Development

cargo fmt --all
cargo clippy --all-targets --locked -- -D warnings
cargo test --locked

Packaging:

.\scripts\package-windows.ps1        # needs: choco install innosetup

./scripts/package-macos.sh           # macOS only; uses built-in tools
./scripts/package-linux.sh           # needs dpkg-deb

Bumping the version means editing Cargo.toml only — the Windows version resource, the Inno installer, the .app bundle, the .deb control file and the registry manifests all read it from there.

Manual test coverage that CI cannot reach is listed in docs/VALIDATION.md.

Releasing

Bump version in Cargo.toml, add a CHANGELOG.md section for it, commit, then:

scripts/release.sh                   # or --dry-run to preview

Pushing the tag triggers GitHub Actions to run the test suite on all three platforms, build the installers, and publish the release using the changelog section as the release notes.

Upgrading from 0.2

• Run the new installer. 0.3 refuses to register menu entries while running from a download folder, disk image, temporary directory or build directory, because those entries break as soon as the location disappears.
• Windows entries moved from HKEY_LOCAL_MACHINE to HKEY_CURRENT_USER. 0.3 removes the old machine-wide keys when it happens to run elevated. If it cannot, run mcopy shell-uninstall --all-users once from an elevated prompt. Leftovers are harmless; the per-user entries take precedence.
• Menus are now per-user. Other accounts on the machine register their own.
• Copy once after upgrading. The 0.2 clipboard payload is discarded rather than migrated, because it carries no session or timestamp to validate.
• Paste now clears after a successful paste. This is the point of the release, but it is a visible behavior change if you relied on pasting the same selection repeatedly. Copy again to paste again.
• macOS: reinstall the app bundle. 0.3 removes LSUIElement, which had suppressed the Dock icon entirely. The bundle identifier also changed from com.mcopy.app to io.github.nakamoz.mcopy, so macOS treats it as a new application and any privacy (Full Disk Access) permission must be granted again.
• install / uninstall are now shell-install / shell-uninstall. The old names still work.
• Thunar users: support was removed. It never actually worked; the previous version only printed instructions to a stream nobody could see.

Troubleshooting

The right-click menu does not appear. Make sure mcopy is installed rather than being run from your downloads folder — the setup window will say so if it is not. Then open mcopy and press Install. On Windows, entries appear under Show more options.

The Paste entry is missing. That is deliberate: it only appears after a successful copy. Run mcopy status to see what is currently copied. It also hides if the copied sources have since been deleted.

The menu opens an older build. Run mcopy shell-uninstall, then install the current version and press Install again.

Items failed during a copy. The progress window names the cause and stays open so you can read it. The log has the full paths.

Nothing happens when I click Paste. 0.3 always shows a window explaining why a paste cannot start. If you see nothing at all, check the log.

macOS says the app is damaged or from an unidentified developer. The build is unsigned. Right-click the app and choose Open, or run xattr -dr com.apple.quarantine /Applications/mcopy.app.

Limitations

• Installers are not code-signed or notarized. Windows SmartScreen and macOS Gatekeeper will warn on first launch.
• macOS keeps the Paste service permanently listed. NSServices visibility is static, and toggling it would mean rewriting the workflow bundle and restarting the pasteboard server on every copy. Pasting with nothing copied shows an explanation instead.
• On Windows 11 the entries appear under Show more options, not the top-level menu. Top-level placement requires an MSIX-packaged IExplorerCommand.
• Thunar is not supported.
• Nautilus 43+ de-emphasizes ~/.local/share/nautilus/scripts. The entries work but are less discoverable than a native extension would be.
• gpui requires a working Vulkan driver on Linux. Software rendering (llvmpipe) works but is slow.
• Client-side decorations and window transparency render inconsistently across Wayland compositors; some tiling window managers ignore taskbar hints.
• The application icon itself is not theme-aware — only the logo drawn inside the windows is. Operating systems do not offer a cheap way to swap an app icon per theme.
• On Windows the binary is GUI-subsystem, so terminal output is best-effort. It is visible when run interactively, but capturing it into a variable from PowerShell is unreliable. Scripts should use exit codes.
• Only x86-64 builds are published. Apple Silicon runs the macOS build under Rosetta.