BucketDock

BucketDock — your S3 browser, on your macOS desktop.

BucketDock is built for AWS S3, Cloudflare R2, Hetzner Object Storage, and other S3-compatible providers when you want a desktop UI instead of the CLI or a browser dashboard.

macOS notice

This is an unsigned developer-preview build. It is not signed with Apple Developer ID and is not notarized.

macOS may say: "the app is damaged or cannot be opened". To run it:

xattr -dr com.apple.quarantine /Applications/BucketDock.app
open /Applications/BucketDock.app

For screenshots and step-by-step first-launch help, see the download and install guide.

macOS Gatekeeper note

Current builds are ad-hoc signed but not Apple-notarized. macOS may block them after download. This is expected for early developer-preview builds.

Official signed and notarized builds are planned later.

Implemented Features

Connections

• Multiple saved connections
• Providers: AWS S3, Cloudflare R2, Hetzner Object Storage, generic S3-compatible endpoints
• Connection testing from the UI
• Optional fixed bucket list for scoped credentials
• Edit and delete connection profiles

Bucket And Object Browsing

• Bucket sidebar per connection
• Folder-like navigation over object prefixes
• Folder rows have a Finder-style disclosure triangle (>) that expands the folder inline and lists its children indented under the parent — without navigating into the folder
• Multi-select in the current listing
• Context menus for common actions
• Empty states and loading skeletons
• Inline filter box in the toolbar (case-insensitive substring match)
• Sortable columns: Name, Type, Storage Class, Size, Modified
• The Name column is resizable so long filenames and folder names do not force the table wider than needed
• Type column shows the real Content-Type returned by the server (fetched via batched HEAD requests after the listing loads); it falls back to the default S3 type (application/octet-stream for files, — for folders) until the HEAD response arrives
• Per-row actions menu (…) for keyboard- and mouse-friendly access
• Modified column shows a short relative time with a full timestamp on hover
• Right-pane Finder-style bucket grid when a connection is selected without a bucket

Object Operations

• Upload files
• Upload folders recursively
• Drag-and-drop file upload into the current prefix
• Download a file
• Download multiple selected items
• Download folders recursively
• Create folder placeholder objects
• Rename objects (use a slash to move into a sub-prefix in the same bucket, e.g. images/photo.jpg)
• Rename / move folders (copy-and-delete across an entire prefix)
• Delete single objects
• Delete multiple selected objects
• Delete prefixes recursively
• Delete confirmation lists every item that will be removed
• Open a file through a presigned URL
• Inline preview for images, audio, video, PDFs, and text files
• Copy files between buckets, including across different connections and providers
• Copy whole folders between buckets (recursive multi-file copy)
• Move files and folders between buckets (copy-then-delete-source, where each source is removed only after its own copy completes — partial / failed / cancelled transfers leave the source untouched)
• Copy / Move destination picker with a folder tree, lazy-expanded children on click, and an inline "New Folder" action so you can carve out a fresh destination without leaving the dialog
• Calculate folder size recursively across all nested subfolders — either from the folder context menu ("Folder Size") or by clicking the — in the Size column of any folder row

Transfer Queue

• Background queue for uploads, downloads, and bucket-to-bucket copies
• Per-transfer status (running, done, failed, cancelled)
• Live progress bar for uploads (per-part for multipart), downloads, and copies
• Cancel a running transfer
• Retry a failed transfer
• Dock at the bottom-right with collapse and clear-finished actions

Metadata

• View object size, modified time, ETag, storage class, and key
• Dedicated "Get Info" view (read-only) and a separate "Edit Headers" editor
• Edit Content-Type
• Edit Cache-Control
• Edit Content-Disposition
• Edit Content-Encoding
• Edit Content-Language
• Edit custom user metadata

Desktop Behavior

• Native macOS window via Tauri
• Native macOS application menu (File, Edit, View, Window, Help) with standard ⌘ accelerators and links to website / docs / GitHub
• Window draggable from the titlebar zone
• Native file and directory pickers
• macOS Keychain secret storage
• Light and dark appearance support
• Persistent sidebar width
• Persistent selected connection, bucket, and prefix state
• Friendly error messages on connection test / save (recognises AccessDenied, SignatureDoesNotMatch, InvalidAccessKeyId, NoSuchBucket, network failures)

Not Implemented Yet

The following items are not implemented in the current codebase and should not be treated as shipped features:

• object tags
• Finder reveal or open-downloaded-file action
• bucket policy inspection

Keyboard Shortcuts

Current object browser shortcuts:

• Delete or Backspace with a selection: delete selected items
• Enter with one selected folder: open that folder
• Cmd+A or Ctrl+A: select all visible items
• Cmd+I or Ctrl+I: open info for one selected file

Architecture

BucketDock uses a split desktop architecture:

Next.js frontend
  -> Tauri command bridge
    -> Rust backend
      -> AWS SDK for S3 / R2 / Hetzner / compatible providers

The frontend never talks directly to S3.

All storage requests are executed by the Rust backend through Tauri commands. That keeps request signing logic and secrets out of the browser runtime.

Local Data And Secrets

Connection metadata is stored in:

~/Library/Application Support/BucketDock/connections.json

Stored there:

• connection name
• provider
• endpoint
• region
• access key id
• optional bucket list

Secret access keys are stored separately in the macOS Keychain under the service name:

com.bucketdock.app

If a connection was created before native Keychain persistence was enabled, edit that connection, enter the Secret Access Key again, and save it once so the secret is written into the macOS Keychain.

Development

Prerequisites

• macOS
• Node.js
• pnpm
• Rust
• Tauri prerequisites for macOS

Tauri setup instructions:

https://tauri.app/start/prerequisites/

Install Dependencies

pnpm install

Run The Desktop App

pnpm tauri dev

This starts the Next.js frontend on port 1420 and launches the Tauri shell.

Run Only The Frontend

pnpm dev --port 1420

This is useful for UI work, but storage operations require the Tauri shell and Rust backend.

Build

pnpm tauri build

The Next.js frontend is exported to out/, and Tauri bundles the macOS app from there.

Build artifacts are written under:

src-tauri/target/release/bundle/

Useful Backend Check

cargo check --manifest-path src-tauri/Cargo.toml

Tests

The project ships two suites that both run in CI before any release build:

# Frontend unit tests (Vitest + jsdom): IPC bridge, app store, copy-to
# self-overwrite guard, MIME helper, secret-leak invariants.
pnpm test

# Backend unit tests (Rust): connection metadata round-trip, validation,
# bucket-filter parsing, S3 key percent-encoding, rename_prefix edges,
# keychain service / bundle account constants.
cargo test --manifest-path src-tauri/Cargo.toml

Provider Setup

AWS S3

Typical AWS S3 setup:

Provider: AWS S3
Region: eu-central-1
Endpoint: leave empty
Buckets: leave empty to auto-list, or set one or more names

Cloudflare R2

Use the account endpoint and keep the bucket name separate.

Standard R2 setup:

Provider: Cloudflare R2
Endpoint: https://<ACCOUNT_ID>.r2.cloudflarestorage.com
Region: auto
Buckets: your-bucket-name

If you have access to more than one bucket, the Buckets field can contain a comma-, space-, newline-, or semicolon-separated list.

Important rules:

• Do not append the bucket name to the endpoint URL
• Keep region set to auto
• For bucket-scoped credentials, enter the exact bucket name in the Buckets field
• For jurisdiction-specific R2 endpoints, paste the full endpoint manually

Correct:

Endpoint: https://<ACCOUNT_ID>.r2.cloudflarestorage.com
Buckets: media-assets
Region: auto

Incorrect:

Endpoint: https://<ACCOUNT_ID>.r2.cloudflarestorage.com/media-assets
Buckets: media-assets
Region: auto

Generic S3-Compatible Providers

Example:

Provider: S3-Compatible
Endpoint: https://s3.example.com
Region: us-east-1
Buckets: my-bucket

Hetzner Object Storage

Example:

Provider: Hetzner Object Storage
Endpoint: https://fsn1.your-objectstorage.com
Region: hidden in the form
Buckets: my-bucket

Troubleshooting Cloudflare R2

SignatureDoesNotMatch

If opening a bucket fails with an error like:

Failed to list objects: S3 error: service error: unhandled error (SignatureDoesNotMatch)

check the following first:

1. The endpoint must be the account endpoint, not an endpoint with the bucket appended.
2. The region must be exactly auto.
3. The bucket name must be entered separately in the Buckets field.
4. If the credentials are scoped to one specific bucket, that bucket must be listed explicitly.
5. Remove any trailing spaces from endpoint, access key id, bucket name, and secret.

For bucket-scoped R2 credentials, BucketDock skips the account-wide ListBuckets call and uses the configured bucket names directly.

Saved Connection Works Only While Editing

If typing the secret into the edit form makes Test pass, but testing the saved connection fails, the saved secret is missing. Open Edit Connection, enter the Secret Access Key again, and click Save so BucketDock can write it into the macOS Keychain.

License

BucketDock source code is licensed under the Apache License, Version 2.0.

See LICENSE for details.

The BucketDock name, logo, icon, domain, and official release assets are not licensed for use in a way that suggests endorsement by the official project.