Documentation

Welcome to the Sundy documentation. Learn how to protect your sensitive data with military-grade encryption and infinite passwords.

Installation

macOS Installation

  1. Download the latest .dmg file from the official website
  2. Open the DMG and drag Sundy to your Applications folder
  3. On first launch, right-click and select "Open" to bypass Gatekeeper
  4. Grant necessary permissions when prompted (Full Disk Access for FUSE)

💡 macFUSE Required

Sundy requires macFUSE to mount encrypted volumes as disks. If not installed, Sundy will guide you through the installation process.

License Activation

After purchase, you'll receive a license key. To activate:

  1. Open Sundy and go to the "About" tab
  2. Copy your Machine ID and use it during purchase
  3. Paste the received license key in the activation field
  4. Click "Activate" to enable full functionality

Quick Start

Creating Your First Encrypted Storage

  1. Launch Sundy
  2. Click "Create New Storage File"
  3. Choose a location and filename for your storage
  4. Set the disk size (minimum 16 MB)
  5. Choose a filesystem (APFS recommended for macOS)
  6. Enable "Randomize entire volume" for maximum security
  7. Click "Create"

Unlocking Your Storage

  1. Open Sundy
  2. Select or drag your storage file
  3. Enter any password
  4. Click "Unlock"
  5. A new disk will appear in Finder

⚠️ Important

Each unique password creates a separate, isolated vault. There is no "master password" — if you forget a password, that vault's data is permanently inaccessible.

System Requirements

Multi-Password System

Sundy's revolutionary multi-password system allows unlimited passwords per storage file. Each password opens a completely separate vault with its own files.

How It Works

When you enter a password, Sundy derives an encryption key using PBKDF2 with 100,000 iterations. This key determines which blocks in the storage file belong to your vault. Different passwords = different keys = different blocks = different data.

Plausible Deniability

The beauty of this system is that there's no way to determine how many passwords (vaults) exist within a storage file. The entire file appears as random data. Even if forced to reveal a password, you can provide one that opens a decoy vault, keeping your sensitive data hidden.

Storage Types

Block File (Recommended)

All encrypted data is stored in a single file. Benefits:

Directory Storage

Encrypted blocks are stored as individual files in a directory. Benefits:

Encryption

Sundy uses industry-standard cryptographic algorithms:

No Signatures

Unlike other encryption tools, Sundy files contain zero identifying markers. No headers, no magic bytes, no metadata. To forensic analysis, your storage file is indistinguishable from random noise.

MAGIC Disk

MAGIC Disk is a revolutionary way to unlock your storage without typing passwords.

Setup

  1. Enable MAGIC Disk in Sundy settings
  2. A small MAGIC volume will be created
  3. Copy specific files to this volume (photos, documents, anything)
  4. The combination of filenames and their content becomes your password

How It Works

Sundy calculates a hash of all files on the MAGIC disk — their names, structure, and content. This hash becomes your encryption key. To unlock, you just need the exact same files.

💡 Pro Tip

Use files that you have multiple copies of (like a specific photo from your phone) as your MAGIC key. You can keep copies on multiple devices for redundancy.

2FA Vault

Store your TOTP (Time-based One-Time Password) secrets securely within your encrypted vault.

Security Model

Unlike phone authenticator apps that keep secrets in memory, Sundy's 2FA vault:

  1. Decrypts the secret only when generating a code
  2. Generates the TOTP code
  3. Immediately destroys the secret from memory

This is the most secure way to use 2FA on a computer — secrets never persist in memory.

Adding 2FA Accounts

  1. Unlock your vault
  2. Go to the "OTP" tab
  3. Enter the account name and secret key
  4. Click "Add" to save

Virtual Disk

When you unlock a vault, Sundy mounts it as a real disk in your system.

Supported Filesystems

Working with Files

The mounted disk works exactly like any other disk. Use Finder, drag & drop files, open documents in any application. All reads and writes are encrypted/decrypted transparently.

Backup & Recovery

Backing Up Your Storage

Simply copy your storage file to a backup location. The entire file is self-contained.

⚠️ Password Recovery

There is no password recovery. Sundy cannot help you recover forgotten passwords. We recommend keeping a secure, offline record of your passwords.

MAGIC Disk Backup

If using MAGIC Disk, ensure you have copies of your key files stored safely. Without the exact files, you cannot unlock that vault.

Command Line

Sundy includes a command-line interface for advanced users and automation.

# Mount a storage file
sundy mount /path/to/storage.sundy -p "your-password"

# Unmount
sundy unmount

# Generate OTP code
sundy otp "Account Name"

Troubleshooting

Disk Won't Mount

Slow Performance

MAGIC Disk Not Detecting Files

Need more help? Contact us at support@sundy.io