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Install Hydra

Every release is on the releases page, a file for each system. The phone app, HydraFE, comes through TestFlight instead.

These beta builds are not signed yet, so the first time you start Hydra your system warns that it does not know who made it. Each section below says how to let it run.

Where Hydra keeps its files

Hydra makes two folders beside where it starts: data, for your settings, layouts, triggers and the characters it knows, and logs, for what each character read. Give Hydra a folder of its own and start it from there. To move Hydra, move the folder: everything goes with it.

On a Mac, the app keeps them in ~/Library/Application Support/Hydra.

Passwords are not in either folder. Hydra keeps one only when you ask, in your computer’s own keyring.

Windows

  1. Download hydra-windows-x86_64.zip.
  2. Extract it into a folder of your own, such as Documents\Hydra. Not into Program Files: Hydra writes its folders beside hydra.exe, and cannot write there.
  3. Double-click hydra.exe. If Windows says Windows protected your PC, choose More info, then Run anyway.

The hub opens, and Hydra’s icon appears in the tray.

A shortcut to hydra.exe works as well: it starts Hydra in the folder hydra.exe is in, unless you change its Start in.

Hydra draws its windows with Vulkan where your graphics card has it, and with DirectX 12 otherwise. If Hydra crashes to the desktop while it plays, and Windows names your graphics driver, choose DirectX 12 under Graphics on Hydra’s General page of Settings and start Hydra again. An overlay such as Overwolf’s, or a recorder’s game capture, hooks into both, and leaving hydra.exe out of them helps too. DirectX 12 can take half a minute to open on some computers; that is the other reason to switch.

macOS

Hydra for macOS runs on Macs with Apple silicon (M1 and later).

  1. Download hydra-macos.dmg, open it, and drag Hydra into Applications.

  2. Open Terminal and let it run, since it is not signed:

    xattr -dr com.apple.quarantine /Applications/Hydra.app

  3. Open Hydra from Applications. The hub opens.

Hydra keeps its files in ~/Library/Application Support/Hydra.

Hydra has no menu bar icon on a Mac. With every window closed it rests in the background and every character plays on. To open its windows again, run this in Terminal:

open -n /Applications/Hydra.app

Linux

Hydra for Linux runs on x86-64 with glibc 2.39 or newer: Ubuntu 24.04 and later, Debian 13, Fedora 40 and later, or another distribution as recent.

  1. Download hydra-linux-x86_64.tar.gz.

  2. Make Hydra a folder, unpack it there, and start it from there:

    mkdir -p ~/Hydra
cd ~/Hydra
tar -xzf ~/Downloads/hydra-linux-x86_64.tar.gz
./hydra

Hydra needs ALSA for sound (libasound.so.2), speech-dispatcher for spoken triggers (libspeechd.so.2) and udev for game controllers (libudev.so.1). Most desktops have them; on Ubuntu or Debian, any missing are installed with:

sudo apt install libasound2t64 libspeechd2

Kept passwords go into your desktop’s keyring, GNOME Keyring or KDE Wallet. Like on a Mac, Hydra has no tray icon: start it again to open its windows.

Updating

On Windows, Hydra updates itself. It looks for a newer release when it starts and every six hours after. When one is out, the hub says so under its header, with What’s new, which opens the release’s notes, and Update. The tray menu offers the same.

Update downloads the release and checks it before using it: every release is signed, and Hydra refuses a file whose signature or checksum does not match. Once it is ready, the hub says it runs from Hydra’s next start, and offers Restart now.

  • Restart now quits every character, the same way Shut down does, and starts Hydra again on the new release, with the hub open. If characters are playing, it names them first and asks. Leave Start them again afterwards ticked and they log back in, each with its team; untick it if you are stepping away. A character whose password is not kept is not logged back in: start it from the hub.
  • Or carry on playing. The new release runs the next time Hydra starts: when you start it yourself, or when it starts fresh after a minute with nothing playing (see How Hydra works).

Two switches on Hydra’s General page of Settings control this. Check for updates is on unless you turn it off. Update on its own is off unless you turn it on; with it on, Hydra downloads a new release as soon as it is out, without asking, and it runs from the next start.

Hydra writes the new program beside the old one, so its folder must be one you can write to; that is another reason not to keep it in Program Files.

The first beta, 0.1.0-beta.1, cannot update itself. Replace it by hand once, as below, and later releases arrive on their own.

By hand, and on a Mac or Linux

Shut Hydra down first, from the hub’s Shut down or the tray. Then replace hydra.exe, the app, or hydra with the new release’s. Your data and logs folders stay as they are.