Install Deucalion¶

What you'll do: download Deucalion and run its installer, which checks what your computer needs, installs anything missing, and adds Deucalion to your app menu.
What you need: Ubuntu 24.04 or newer (22.04 for the command line only), an internet connection, your administrator password.
How long it takes: about 5 minutes.

The installer is a command you run once in a terminal. If you have never used a terminal, see Opening a terminal; you only need to copy and paste.

Step by step¶

Open a terminal: press Ctrl+Alt+T.
Install git, the tool that downloads Deucalion. Copy this line, paste it into the terminal with Ctrl+Shift+V, and press Enter. Type your password when asked (nothing appears while you type), then press Enter again. If git is already installed, it says so and changes nothing.
```
sudo apt install git
```

Download Deucalion into a folder called Deucalion in your home folder:

git clone https://github.com/Dimitrios-Kafetzis/Deucalion.git ~/Deucalion

Go into the folder you just downloaded and start the installer:
```
cd ~/Deucalion
./install.sh
```
The installer first lists what Deucalion needs, with a ✓ for what is already there and a ✗ for what is missing. If something is missing, it asks before installing it: type y and press Enter, then type your password when asked.
It then asks whether to install VeraCrypt. You need it only if you want an encrypted drive that can also be opened on Windows or macOS (see Choosing a drive). If you are not sure, answer y: it does no harm.
When it says Done, Deucalion is installed. You see something like this:

$ ./install.sh
Checking what Deucalion needs…
What Deucalion needs
  ✓ python3-gi       talking to Ubuntu's disk service and the app
  ✓ gir1.2-gtk-4.0   the app window
  ✓ gir1.2-adw-1     the app's GNOME look
  ✓ udisks2          preparing, unlocking and mounting drives
  ✓ cryptsetup       opening encrypted drives
  ✓ exfatprogs       creating exFAT drives (readable on Linux, macOS and Windows)
  ✓ pkexec           asking for the administrator password
  ✓ dconf-cli        saving desktop settings
  ✓ gnupg            verifying the VeraCrypt download
  ✗ veracrypt        VeraCrypt-encrypted drives (optional)

Install VeraCrypt? It is needed only for VeraCrypt-encrypted drives (readable on Linux, macOS and Windows). The official package is downloaded and its signature checked before installing. [y/N] y
Looking up the latest VeraCrypt release…
Downloading veracrypt-1.26.29-Ubuntu-24.04-amd64.deb …
Checking the signature (VeraCrypt key 680D16DE)…
Signature OK. Installing VeraCrypt (asks for your administrator password)…
…
Everything Deucalion needs is installed.

Installing Deucalion into /home/alex/.local/share/deucalion
Done. Open Deucalion from the app menu, or run: deucalion

The … line stands for many lines of installation output from Ubuntu's package manager.

What you have now: Deucalion in your app menu (search for "Deucalion") and the deucalion command in the terminal.

On Ubuntu 22.04

The app needs Ubuntu 24.04 or newer. On 22.04 the installer says "No app menu entry: The app needs Ubuntu 24.04 or newer …" and installs only the deucalion command, which does everything the app does. See the command line.

If deucalion says command not found right after installing

On a computer where nothing was installed this way before, Ubuntu adds the folder that holds the deucalion command (~/.local/bin) to its search path only when you log in. Log out and back in once. Until then, you can type ~/.local/bin/deucalion instead of deucalion.

Recommended: install the administrator helper¶

A few things Deucalion does need administrator rights: saving your Wi-Fi passwords and protected system settings, using a VeraCrypt drive, and installing apps during a rebuild. Deucalion does them through a small administrator helper (see Administrator access).

Installing the helper system-wide is recommended. Run:

cd ~/Deucalion
./install.sh --system-helper

$ ./install.sh --system-helper
Checking what Deucalion needs…
What Deucalion needs
  ✓ python3-gi       talking to Ubuntu's disk service and the app
  ✓ gir1.2-gtk-4.0   the app window
  ✓ gir1.2-adw-1     the app's GNOME look
  ✓ udisks2          preparing, unlocking and mounting drives
  ✓ cryptsetup       opening encrypted drives
  ✓ exfatprogs       creating exFAT drives (readable on Linux, macOS and Windows)
  ✓ pkexec           asking for the administrator password
  ✓ dconf-cli        saving desktop settings
  ✓ gnupg            verifying the VeraCrypt download
  ✓ veracrypt        VeraCrypt-encrypted drives (optional)
Everything Deucalion needs is installed.

Installing Deucalion into /home/alex/.local/share/deucalion
Installing the administrator helper (asks for your password)…
Done. Open Deucalion from the app menu, or run: deucalion

It asks for your password once. It puts a copy of the helper in /usr/local/libexec/deucalion/, owned by the administrator, so other programs running as you can't change the code that runs with administrator rights. It also gives you a clearer password prompt: "Deucalion needs administrator access to save or restore protected system settings, or to use an encrypted VeraCrypt drive", and Ubuntu remembers your password for a few minutes so you aren't asked again and again.

Without it, Deucalion still works: it runs the helper from its own folder, and Ubuntu shows a generic password prompt.

What the installer checks: `deucalion deps`¶

The installer runs deucalion deps --install. You can run deucalion deps yourself at any time to see what is installed:

$ deucalion deps
What Deucalion needs
  ✓ python3-gi       talking to Ubuntu's disk service and the app
  ✓ gir1.2-gtk-4.0   the app window
  ✓ gir1.2-adw-1     the app's GNOME look
  ✓ udisks2          preparing, unlocking and mounting drives
  ✓ cryptsetup       opening encrypted drives
  ✓ exfatprogs       creating exFAT drives (readable on Linux, macOS and Windows)
  ✓ pkexec           asking for the administrator password
  ✓ dconf-cli        saving desktop settings
  ✓ gnupg            verifying the VeraCrypt download
  ✓ veracrypt        VeraCrypt-encrypted drives (optional)

Package	Needed for
`python3-gi`	talking to Ubuntu's disk service, and the app
`gir1.2-gtk-4.0`, `gir1.2-adw-1`	the app's window and its GNOME look
`udisks2`	preparing, unlocking and mounting drives
`cryptsetup`	opening encrypted drives
`exfatprogs`	creating exFAT drives (readable on Linux, macOS and Windows)
`pkexec`	asking for the administrator password
`dconf-cli`	saving desktop settings
`gnupg`	checking the VeraCrypt download's signature
`veracrypt`	VeraCrypt-encrypted drives (optional)

On a normal Ubuntu Desktop, everything except VeraCrypt is usually already installed. See deucalion deps for all options.

How VeraCrypt is installed¶

VeraCrypt is not in Ubuntu's own software collection. Deucalion downloads the official package from VeraCrypt's release page on GitHub and installs it only if:

its digital signature was made by VeraCrypt's signing key (Deucalion knows the key's fingerprint, 5069A233D55A0EEB174A5FC3821ACD02680D16DE, and refuses any other key, and any revoked or expired one);
it is version 1.26.29 or newer;
it really comes from VeraCrypt's GitHub release address.

If any check fails, nothing is installed. You can also install VeraCrypt yourself from veracrypt.fr.

Other ways to run Deucalion¶

You don't have to install Deucalion to use it:

From the downloaded folder: run ~/Deucalion/bin/deucalion (add a command after it, such as ~/Deucalion/bin/deucalion status). With no command, it opens the app.
From a backup drive: every drive Deucalion prepares (except a fully encrypted one) has a Deucalion-Tool folder with a copy of Deucalion. On a new computer, open a terminal in that folder and run bin/deucalion. This is how a rebuild usually starts.

Updating¶

Download the new version and run the installer again:

cd ~/Deucalion
git pull
./install.sh

If you installed the administrator helper and it changed, the installer updates it too (it asks for your password). Deucalion refuses to use a helper from another version and tells you to run ./install.sh --system-helper.

Uninstalling¶

cd ~/Deucalion
./install.sh --uninstall

This removes the program, the deucalion command, the app menu entry and icon, and the administrator helper (asking for your password if it was installed). Your backups and your settings (~/.config/deucalion) are kept. VeraCrypt and the Ubuntu packages Deucalion needed stay installed; remove them with Ubuntu's software tools if you no longer need them.

Installer options¶

Option	What it does
(none)	Check and install what is needed (asking first), then install Deucalion for you.
`--system-helper`	Also install the administrator helper system-wide (asks for your password).
`--uninstall`	Remove Deucalion (keeps your backups and settings).
`--veracrypt`	Install VeraCrypt without asking.
`--no-veracrypt`	Don't install VeraCrypt and don't ask.
`--yes`, `-y`	Install missing packages without asking.

Next: Your first backup.