Hyperdrive.el User Manual

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Hyperdrive.el User Manual

Hyperdrive is a P2P, real-time, local-first, versioned filesystem designed for easy peer-to-peer file sharing. hyperdrive.el is an independent project built by USHIN which provides an Emacs interface for managing hyperdrives.

hyperdrive.el is in early development. If something breaks, please see Troubleshooting.

This manual is for hyperdrive.el version 0.4-pre.

Table of Contents

1 Freedom to copy

Copyright © 2023, 2024 USHIN, Inc.

Permission is granted to copy, distribute and/or modify this document under the terms of the GNU Free Documentation License, Version 1.3 or any later version published by the Free Software Foundation; with no Invariant Sections, with the Front-Cover Texts being “A GNU Manual,” and with the Back-Cover Texts as in (a) below. A copy of the license is included in the section entitled “GNU Free Documentation License.”

(a) The FSF’s Back-Cover Text is: “You have the freedom to copy and modify this GNU manual.”

2 Installation

2.1 Install Emacs

hyperdrive.el requires GNU Emacs version 28.1 or later.

2.2 Install hyperdrive.el

hyperdrive.el can be installed from NonGNU ELPA with M-x package-refresh-contents then M-x package-install RET hyperdrive.

After installing with NonGNU ELPA, you can later upgrade to a newer version of hyperdrive.el by running M-x package-refresh-contents then M-x package-upgrade RET hyperdrive. On Emacs 28, If package-upgrade is not available as a command, display the list of packages with M-x list-packages, select hyperdrive, and click the Install button.

2.3 Install hyper-gateway-ushin

hyperdrive.el relies on hyper-gateway-ushin for talking to the hypercore network.

After installing hyperdrive.el (see Install hyperdrive.el), run M-x hyperdrive-install to download and install the gateway.

Alternatively, follow the manual installation instructions.

3 Example configuration

After following the installation instructions, you can add this snippet to your ~/.emacs.d/init.el file. This code will make the keyboard shortcut C-c h (hold the Control key and tap c, then release both and tap h) open the hyperdrive menu command. It will also enable the “Hyperdrive” menu bar:

(when (package-installed-p 'hyperdrive)
  (global-set-key (kbd "C-c h") #'hyperdrive-menu)
  (hyperdrive-menu-bar-mode 1))

With (use-package)use-package:

(use-package hyperdrive
  :bind ("C-c h" . hyperdrive-menu)
  :init (hyperdrive-menu-bar-mode 1))

4 Usage

Be careful about what you share!
When you upload a file, beware:
  You may delete your own copy,
  But gone it may not be.
On the network it still may be there.

4.1 Install the gateway

Run M-x hyperdrive-install to download and install the gateway program (see hyper-gateway-ushin):

Command: hyperdrive-install

Download and install the gateway. Prompts for confirmation before downloading.

Command: hyperdrive-cancel-install

Cancel installation in progress.

4.3 Hyperdrive menu command

M-x hyperdrive-menu is a keyboard-driven interface to many hyperdrive.el commands. With the menu open, press one of highlit keys or key combinations to invoke the command displayed next to it. Different commands are available in hyperdrive-menu when you’re inside a hyperdrive file, directory, or neither.

While inside the hyperdrive-menu, press ? twice to open this hyperdrive.el info manual. You can also press ? followed by a command’s key sequence to get help for that command. (more tips on getting help)

If you press C-u (universal prefix argument) before a key sequence, the command may behave differently, e.g., by prompting for more information. You can jump between hyperdrive-menu commands with the up and down arrow keys. Press C-g to close the menu.

Command: hyperdrive-menu

Show the hyperdrive menu interface.

For more on this type of user interface, please refer to the (transient)Transient documentation. To learn about the commands available in hyperdrive-menu, read on!

4.4 Start/stop the gateway

To connect with peers, you’ll need to start the gateway (see hyper-gateway-ushin). The current running status of the gateway can be seen in hyperdrive-menu (see Hyperdrive menu command) and in the “Hyperdrive” menu bar (see Menu bar support).

Command: hyperdrive-start

Start the gateway.

User Option: hyperdrive-gateway-ready-hook

Hook run when the gateway becomes responsive after hyperdrive-start. One of the default hooks, hyperdrive-check-gateway-version, will warn you if you’re running an outdated version of the gateway.

Command: hyperdrive-stop

Stop the gateway.

Command: hyperdrive-restart

Restart the gateway.

Command: hyperdrive-gateway-version

Say the version of the gateway which is running.

4.4.1 Advanced gateway customization

User Option: hyperdrive-gateway-start-function

Function run to start the gateway. By default, hyperdrive.el will start the gateway as an Emacs subprocess.

User Option: hyperdrive-gateway-stop-function

Function run to stop the gateway.

User Option: hyperdrive-gateway-live-predicate

Function run to check that the gateway process is live.

4.5 Open a hyperdrive

You can open a hyperdrive folder or file by pasting in a hyper:// URL after M-x hyperdrive-open-url. Try loading USHIN’s hyperdrive:

Command: hyperdrive-open-url

Open a hyperdrive file or directory by its hyper:// URL.

The following commands let you select and visit one of the hyperdrives you’ve already created or visited:

Command: hyperdrive-find-file

Open a hyperdrive file or directory by choosing one of your known hyperdrives and a path inside it. Like find-file, this command can be used to create a new file inside your own hyperdrives.

Command: hyperdrive-view-file

Like hyperdrive-find-file, but open the file in (emacs)view-mode.

4.5.1 Directory view

hyperdrive.el offers a Dired-like (see (emacs)Dired) interface for exploring hyperdrive directories. The following keybindings are available inside the directory view by default:

Key: n (hyperdrive-ewoc-next)
Key: p (hyperdrive-ewoc-previous)

Move between entries.

Key: RET (hyperdrive-dir-find-file)

Open the file or directory at point.

Key: o (hyperdrive-dir-find-file-other-window)
Key: <mouse-1>
Key: <mouse-2>

Open the file or directory at point in a new window.

Key: v (hyperdrive-dir-view-file)

Open the file or directory at point in (emacs)view-mode.

Key: ^ (hyperdrive-up)

Go up to the parent directory.

Key: g (revert-buffer)

Refresh the directory to display potential updates.

Key: s (hyperdrive-dir-sort)

Sort directory contents by the current column. To sort by a different column, click on the column header or use the universal prefix argument (C-u s).

Key: d (hyperdrive-dir-download-file)

Download the file at point to disk.

Key: D (hyperdrive-delete)

Delete the file or directory (recursively) at point.

Key: F (hyperdrive-forget-file)

Delete your local copy of the file for the current buffer.

Key: H (hyperdrive-dir-history)

Open the version history (see View the hyperdrive version history) of file at point.

Key: w (hyperdrive-dir-copy-url)

Copy the URL of the file or directory at point.

Key: j (imenu)

Open imenu to quickly jump to a file in the current directory.

Key: ? (hyperdrive-menu)

Open hyperdrive-menu (see Hyperdrive menu command).

Key: + (hyperdrive-create-directory-no-op)

This command signals an error, because you cannot create empty directories (see No empty directories).

You can customize the directory view with the following options:

User Option: hyperdrive-directory-display-buffer-action

Display buffer action for hyperdrive directories. Passed to display-buffer, which see.

User Option: hyperdrive-directory-sort

Column by which directory entries are sorted by default. Internally, a cons cell of (COLUMN . DIRECTION), the COLUMN being one of the directory listing columns (name, size, or mtime) and DIRECTION being one of :ascending or :descending.

4.5.2 File view

The following keybindings are available inside the file view by default:

Key: C-x x g (hyperdrive-revert-buffer-quick)

Refresh the file to display potential updates. This command remaps the global revert-buffer-quick keybinding.

Key: C-x C-j (hyperdrive-up)

Jump to the parent hyperdrive directory from a hyperdrive file or directory buffer. This command remaps the global dired-jump keybinding.

For security reasons, hyperdrive.el does not enable major modes based on file extension unless the hyperdrive has been marked as “safe” with M-x hyperdrive-mark-as-safe (see Mark a hyperdrive as safe).

The following customization options affect how files are displayed:

User Option: hyperdrive-render-html

Control how HTML hyperdrive files are displayed. By default, HTML pages are rendered in Emacs with (eww)EWW. If nil, raw HTML will be displayed.

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4.5.3 Unknown paths

When you attempt to load a file or folder that doesn’t appear to exist, hyperdrive.el will prompt you to take action:

  • h (history) to open the version history for that file. This only works for files, not folders (see No directory version history)
  • u (up) to open the parent directory containing that file or folder
  • r (recurse) to go up the directory tree until a directory is found or until you get to the root directory.
  • q (exit) to exit,
  • ? (help) to show a help message.

If you attempt to load the root directory (hyper://PUBLIC-KEY/) of a hyperdrive with a valid-looking public key which you’ve never loaded before and for which no peers are currently found, hyperdrive.el should warn you that no peers were found for that drive. This might mean that the drive doesn’t exist or just that you’re not connected to anyone who knows about it.

If you attempt to load a file or directory for a hyperdrive with a malformed public key, hyperdrive.el should ask you to double-check the URL.

4.6 Create a hyperdrive

You can have multiple hyperdrives, each one containing its own set of files. Run M-x hyperdrive-new then type in a seed (see Seeds) to create a new hyperdrive. That seed will be combined with your secret master key (see Master key) to produce a public key (see Public keys) that uniquely identifies that hyperdrive.

Command: hyperdrive-new

Create a new hyperdrive from a seed string.

When you create a new drive, your chosen seed is used as its petname (see Petnames) by default.

4.7 Write to a hyperdrive

After modifying a file in one of your hyperdrives, save-buffer will silently update the current hyperdrive file with the new content.

Key: C-x C-s (save-buffer)

Save the current hyperdrive file buffer to its location.

Key: C-x s (save-some-buffers)

Save all modified hyperdrive file buffers to their locations. This command’s primary purpose is to save normal file buffers, and hyperdrive.el has integrated with it.

hyperdrive.el will prompt to save modified hyperdrive files before exiting Emacs. If you want the command save-some-buffers to always prompt to save hyperdrive files in addition to regular files, set save-some-buffers-default-predicate to t.

Command: hyperdrive-write-buffer

Write the current buffer to a hyperdrive by choosing one of hyperdrives you have created as well as the path in that hyperdrive where you want to store the file.

4.9 Delete a hyperdrive file

Please note that deleted files can be accessed by loading a prior version of the hyperdrive (see View the hyperdrive version history).

Command: hyperdrive-delete

Delete the hyperdrive file in the current buffer.

This command also has a keybinding in the directory view (see Directory view).

4.10 Forget a hyperdrive file

It is possible to “forget” your local copy of a hyperdrive file in order to save disk space. “Forgetting” a file does not delete the file from the hyperdrive and does not increment the hyperdrive’s version number.

Command: hyperdrive-forget-file

Delete your local copy of the file for the current buffer.

This command also has a keybinding in the directory view (see Directory view).

4.11 View the hyperdrive version history

Hyperdrives are versioned, meaning that you can explore the history of changes made to hyperdrive files (see Versioning).

Command: hyperdrive-open-previous-version

Open the previous version of the current hyperdrive file or directory.

Command: hyperdrive-open-previous-version

Open the next version of the current hyperdrive file or directory.

Command: hyperdrive-open-at-version

Open the current hyperdrive file or directory at a specific version number. To open the file or directory at its hyperdrive’s latest version, leave the version blank.

The following keybindings are available when visiting an old version of a hyperdrive file (hyperdrive-blob-mode):

Key: n (hyperdrive-open-next-version)
Key: p (hyperdrive-open-previous-version)

Traverse version history for the current file.

Key: q (kill-current-buffer)

4.11.1 History buffer

The history buffer displays the entire known history of a hyperdrive file. For an explanation of how it works, see Partial version data.

Command: hyperdrive-history

Open the history buffer for the current hyperdrive file. To open the history for a different file, use the universal prefix argument like this: C-u M-x hyperdrive-history.

The following keybindings are available inside the history view by default:

Key: n (hyperdrive-ewoc-next)
Key: p (hyperdrive-ewoc-previous)

Move between entries.

Key: + (hyperdrive-history-fill-version-ranges)

Load version history for unknown version ranges.

Key: RET (hyperdrive-history-find-file)

Open the file at the start of the version range at point.

Key: o (hyperdrive-history-find-file-other-window)
Key: <mouse-1>
Key: <mouse-2>

Open the file at the start of the version range at point in a new window.

Key: v (hyperdrive-history-view-file)

Open the file at the start of the version range at point in (emacs)view-mode.

Key: w (hyperdrive-history-copy-url)

Copy the URL of the file at the start of the version range at point.

Key: d (hyperdrive-history-download-file)

Download the file at the start of the version range at point.

Key: = (hyperdrive-history-diff)

Display the differences between the version at point and the prior version.

To act on the latest known version of the file, use these keybindings on the header line displaying the file description.

You can customize the history view:

User Option: hyperdrive-history-display-buffer-action

Display buffer action for hyperdrive history buffers. Passed to display-buffer, which see.

4.12 Describe a hyperdrive

To see information about a hyperdrive, such as its public key, seed, petname, nickname, domains, writability, local disk usage, or other metadata, run hyperdrive-describe-hyperdrive. For more on what this information means, see Naming.

Command: hyperdrive-describe-hyperdrive

Display the description of the hyperdrive containing the current file or directory. To describe a different hyperdrive, use the universal prefix argument: C-u M-x hyperdrive-describe-hyperdrive.

4.13 Name a hyperdrive

hyperdrive.el supports different ways to identify hyperdrives (see Naming). The following commands can be used to name hyperdrives:

Command: hyperdrive-set-petname

Set the petname (see Petnames) of the hyperdrive for the current hyperdrive file or directory. You can’t use the same petname for multiple hyperdrives. To set the petname of a different hyperdrive, use the universal prefix argument: C-u M-x hyperdrive-set-petname.

Command: hyperdrive-set-nickname

Set the nickname (see Nicknames) of the hyperdrive for the current hyperdrive file or directory. You can only set the nickname for a hyperdrive which you previously created. To set the nickname of a different hyperdrive, use the universal prefix argument like this: C-u M-x hyperdrive-set-nickname.

4.14 Bookmark a hyperdrive

You can use the built-in bookmark-set, bookmark-jump, and bookmark-list functions to store and jump to a hyperdrive file or directory.

Command: hyperdrive-bookmark-jump

Select a hyperdrive bookmark and jump to it.

Command: hyperdrive-bookmark-list

View a list of hyperdrive bookmarks.

4.15 Stream audio and video

When you use hyperdrive-find-file or some other command to open a streamable audio/video file, Emacs will use an external program to stream that video from the network. After the stream finishes, the audio/video file is stored locally.

User Option: hyperdrive-stream-player-command

Command used to play streamable URLs externally. Default uses mpv. There also exists a preconfigured option for VLC media player.

4.16 Download hyperdrive files

You can “download” a hyperdrive file to your local filesystem, meaning that hyperdrive.el will (1) download the file from the network if it hasn’t done so already and then (2) copy the file contents to a file-path on your machine of your choosing. The following commands may be run while offline.

Command: hyperdrive-download

Download a hyperdrive file by selecting a hyperdrive and a path.

Command: hyperdrive-download-url

Download a hyperdrive file by pasting in a hyper:// URL.

User Option: hyperdrive-download-directory

Location where hyperdrive-download-url will download files. Defaults to eww-download-directory or, if not bound, the home directory.

4.17 Upload files from your filesystem

If you already have a file on your local filesystem that you’d like to put on a hyperdrive, you can “upload” it. Note that the following commands add files to a hyperdrive, but those files are not automatically “uploaded” to anyone else’s machine in the traditional sense. Files are only shared on the network when other peers request them from your node. The following commands may be run while offline.

Command: hyperdrive-upload-file

Upload a single file from your filesystem. By default, the selected file will be placed in your hyperdrive’s root directory, but you can edit the filepath before uploading.

Command: hyperdrive-upload-files

Upload multiple files from your filesystem. The selected files will be uploaded into the same target directory in your hyperdrive.

On Emacs 29+, you can upload an image which you previously copied to your clipboard from an external program with M-x yank-media.

4.17.1 Mirror a whole directory

For uploading more than a few files, you can use hyperdrive-mirror.

Command: hyperdrive-mirror

Upload a directory, mirroring its subdirectory structure in your hyperdrive. This command prompts for a source directory on your local filesystem from which to upload files as well as a hyperdrive and target directory inside of it where the files will end up.

The source and target directories will be compared, and only the files which are “new locally” (they don’t already exist on the drive) or “newer locally” (they have been locally modified since a previous upload) will be uploaded. Files which are the “same” (they have the same timestamp as in the drive) or are “older locally” (they have been modified on the drive more recently than on the filesystem) will not be uploaded.

With a universal prefix argument (C-u M-x hyperdrive-mirror), it additionally prompts for a filter argument to programmatically determine which files will be considered for upload. With two universal prefix arguments (C-u C-u M-x hyperdrive-mirror), matching files will be uploaded without the confirmation step.

As a confirmation step, hyperdrive-mirror displays each file to be uploaded alongside the URL in the hyperdrive where it will end up. The following keybindings are available in hyperdrive-mirror-mode:

Key: C-c C-c (hyperdrive-mirror-do-upload)

Upload all of the files in the “To Upload” section.

Key: TAB (magit-section-toggle)

Fold or unfold the section at point.

4.18 Mark a hyperdrive as safe

For security reasons, hyperdrive.el does not enable major modes based on file extension unless the hyperdrive has been marked as “safe.”

Command: hyperdrive-mark-as-safe

Mark a hyperdrive as “safe,” which will cause major modes to be automatically be enabled based on file extension when opening files within that hyperdrive. Files in hyperdrives which are “unsafe” (the default) are opened in fundamental-mode.

4.19 Purge a hyperdrive

Data which has been purged from your local machine may still be available on the network.

Data which has been purged from your local machine may not be recoverable.

Command: hyperdrive-purge

Remove all data related to a hyperdrive. This command will prompt for confirmation before deleting anything. In addition to the hyperdrive’s file content and metadata, hyperdrive-purge also deletes relevant metadata persisted in the hyperdrive-hyperdrives and hyperdrive-version-ranges variables.

4.20 Non-interactive use

In writing your own functions to extend hyperdrive.el, you can use hyperdrive-by-slot to access a hyperdrive by its metadata:

Function: hyperdrive-by-slot

This function accepts a hyperdrive seed, petname, or public key, and returns the hyperdrive struct.

4.20.1 Non-interactive use example: hyperdrive-mirror

You can use the following snippet to recursively upload all of the files from your local filesystem’s ~/blog/ directory into the /blog/ directory of a hyperdrive you previously created with petname "foo":

 (hyperdrive-by-slot 'petname "foo")

To upload the same files without confirmation, add :no-confirm t.

Now let’s say that you want to upload only those files tagged as “public” using Protesilaos Stavrou’s Denote file-naming scheme. The following snippet includes a FILTER key whose value is a regular expression against which every expanded filename will be tested.

 (hyperdrive-by-slot 'petname "foo")
 :filter "_public")

Alternatively, you could select files by tag with Karl Voit’s filetags. Either way allows for a “non-splitting” approach where public and private files exist in the same directory.

FILTER may also be a function, which receives the expanded filename as its only argument. For example, the following snippet will mirror only those files in ~/blog/ which are smaller than 5MB:

 (hyperdrive-by-slot 'petname "foo")
 :filter (lambda (file) (> (* 5 1024 1024)
                       (file-attributes file)))))

4.21 Org-transclusion integration

The hyperdrive-org-transclusion package adds support for transcluding hyperdrive files and parts of hyperdrive files with org-transclusion.

To use this feature, please install hyperdrive-org-transclusion with M-x package-install RET hyperdrive-org-transclusion and then add the following snippet to your configuration:

(with-eval-after-load 'org-transclusion
  (add-to-list 'org-transclusion-extensions 'hyperdrive-org-transclusion)
  (require 'hyperdrive-org-transclusion))

You can then run M-x org-transclusion-add on the following link to transclude the Org heading with the property CUSTOM_ID: emacs inside the /software.org file inside the USHIN hyperdrive:

#+transclude: [[hyper://aaj45d88g4eenu76rpmwzjiabsof1w8u6fufq6oogyhjk1ubygxy/software.org#%3A%3A%23emacs]]

4.22 Miscellaneous features

4.22.1 Find file at point integration

If you have enabled find-file-at-point (ffap) bindings with M-x ffap-bindings, you can open a hyperdrive link by putting the point on it and pressing C-x C-f.

4.22.2 Embark integration

Embark users can run embark-act in the hyperdrive-complete-hyperdrive completing-read interface in order to select an alternative action for the selected hyperdrive.

4.22.3 Webjump integration

You can jump to a hyper:// link with M-x webjump after adding it to webjump-sites:

 '("USHIN Hyperdrive" . "hyper://aaj45d88g4eenu76rpmwzjiabsof1w8u6fufq6oogyhjk1ubygxy/"))

5 Concepts

5.1 Hyperdrive

Hyperdrive is a virtual filesystem which you can use to share files on the peer-to-peer (P2P) hyper network. It’s a folder with a globally unique link starting with hyper:// that you can put files into and other peers can pull files out of (if they have the link).

Anyone with the link to your hyperdrive can download its contents directly from your computer. There’s no need to make an account or rely on a third party to pass the data along. Anyone who has a copy of the content in your hyperdrive can serve it to others. This means that your hyperdrive can circulate on the hyper network even when you’re offline.

Hyperdrive is single-writer, meaning that you are the only one who change a hyperdrive that you’ve created. Files in a hyperdrive are cryptographically signed to ensure that the files you share aren’t tampered with.

You can make as many hyperdrives as you like; the only limitation is your own disk space.

Hyperdrive is offline-first since you can view files which were previously downloaded even when your machine is disconnected from the rest of the network. It’s also local-first, since you can connect with peers on a local network even without an internet connection.

Unlike BitTorrent, another P2P protocol for sharing files, hyperdrives are mutable. If you share a link to your hyperdrive and then later add, update, or delete files inside it, peers will be able to access your latest changes at the same link. When you make revisions to a hyperdrive, the old versions of your files can still be accessed by peers on the network. See Versioning for more information.

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5.1.1 Sparse replication

Hyperdrives are sparsely replicated, meaning that peers can download particular files from a hyperdrive without having to download the whole drive. This reduces both load times and disk usage.

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5.1.2 Versioning

Hyperdrives are versioned, meaning that it is possible to explore a hyperdrive as it was in the past. Version numbers indicate the hyperdrive’s version. For example, hyper://PUBLIC-KEY/$/version/50/ refers to the fiftieth version of the hyperdrive identified by PUBLIC-KEY. If you want to load the latest version, leave out the /$/version/N part. For example, if you run…

M-x hyperdrive-open-url RET hyper://PUBLIC-KEY/foo.org RET

…then hyperdrive.el will attempt to find /foo.org inside the latest version of that hyperdrive.

Whenever you add a file, remove a file, or change a file, the hyperdrive’s version number gets incremented by 1. The version number tells you how many times the hyperdrive has been modified, not how many times a particular file has been modified. For example, let’s say that the current version of your hyperdrive at hyper://PUBLIC-KEY/ is 50. If you add a new file at hyper://PUBLIC-KEY/bar.org, the latest version of your hyperdrive will become 51.

Since /bar.org did not exist before version 51, if you attempt to load hyper://PUBLIC-KEY/$/version/50/bar.org, hyperdrive.el should warn you that nothing exists at that URL. If you add another file at hyper://PUBLIC-KEY/quux.org, your hyperdrive’s latest version will become 52. For the moment, hyper://PUBLIC-KEY/bar.org, hyper://PUBLIC-KEY/$/version/51/bar.org, and hyper://PUBLIC-KEY/$/version/52/bar.org, all point to the same version of /bar.org. If you then make a change to /bar.org, your hyperdrive’s latest version will become 53. Now hyper://PUBLIC-KEY/bar.org and hyper://PUBLIC-KEY/$/version/53/bar.org will point to the latest version of /bar.org, while the original version will be available at version 51 or 52.

Here’s the mockup of the history view for /bar.org so far, the hyperdrive’s latest version being 53:

Version rangeexists

The table shows that /bar.org was created at version 51 and modified at version 53. The final version range number in the table is 53, indicating that the hyperdrive’s latest version is 53.

If you delete /bar.org then try to load hyper://PUBLIC-KEY/bar.org, hyperdrive.el will open an empty buffer for you to author a new file. If another peer attempts to load that URL, hyperdrive.el will warn "URL not found", since you are the only one who can modify your drive. All peers can view the old file contents at the versioned URLs.

Since only the current version of a hyperdrive file can be updated, hyperdrive.el sets the buffer to read-only whenever a version number is specified in a hyper URL. Partial version data

Because hyperdrives are sparsely replicated (see Sparse replication), hyperdrive.el might not know the full version history of a file. When the gateway (see hyper-gateway-ushin) loads a file from the network, it also loads some version metadata about that file. Specifically, it loads the hyperdrive version number at which the file was modified. For example, if I load the most recent version of /bar.org from your hyperdrive (see the prior section), my gateway would also load the start of the version range containing the most recent version of /bar.org. My hyperdrive.el knows the latest version number of your drive, but with partial version history, the history of /bar.org in your drive looks like this for me:

Version rangeexists

If I run M-x hyperdrive-previous while looking at the latest version of /bar.org, hyperdrive.el will display /bar.org at version 52. In the background, the gateway will report that /bar.org at version 52 of your hyperdrive was actually created at version 51 of your hyperdrive:

Version rangeexists

Running hyperdrive-previous while looking at /bar.org at version 51 or 52 will send a request for /bar.org at version 50. The gateway will report that /bar.org does not exist at version 50, but it won’t report whether /bar.org ever existed before version 50. For example, /bar.org might have been created at version 6, deleted at 14, then created again at version 51. hyperdrive.el will keep sending requests to the network (up to hyperdrive-fill-version-ranges-limit) until the history view looks like:

Version rangeexists
1-50no No directory version history

Version history for directories is not implemented for a design reason and technical reason:

  • Directories have neither mtime nor size metadata, so a history view for directories wouldn’t be that useful.
  • Implementation of directory history would be somewhat ugly, since it requires either
    1. storing an entry for each directory in hyperdrive-version-ranges, which doesn’t optimally normalize version history data, or
    2. generating directory history based on the history of the files it contains, which can never prove that a directory doesn’t exist.

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5.1.3 Master key

The secret master key is combined with a seed (see Seeds) to generate a new public key for a hyperdrive when you run hyperdrive-new. Your master key is generated automatically by the gateway.

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5.2 hyper-gateway-ushin

Hyper-gateway-ushin handles interactions with hyperdrive under the hood, and it runs a local HTTP server which offers a Fetch API to access the Hyperdrive network. In hyperdrive.el, P2P interactions consist mostly of, e.g., GET requests to download files and PUT requests to write files to a hyperdrive.

5.3 Naming

Inspired by Marc Stiegler’s An Introduction to Petname Systems, hyperdrive.el names drives in a three different ways:

Public key

public, globally unique, not human-memorable


public, not necessarily unique, human-memorable


private, locally unique, human-memorable

If hyperdrive.el is like a phonebook, then public keys are phone numbers, nicknames are how your contacts introduce themselves, and petnames are the names you actually write down.

Each drive may also have one or both of the following attributes:


string used to generate public key

DNS domain

public, globally unique, human-memorable

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5.3.1 Public keys

Public keys are globally unique identifiers for hyperdrives. They make up the first part of a hyper:// URL. Public keys are 52-character-long z-base-32 encoded keys generated from your master key (see Master key) and a seed string. When you run hyperdrive-new and type a new seed, the gateway automatically generates a new public key.

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5.3.2 Nicknames

Nicknames are public, memorable names which you can give to your own hyperdrives to make them easier for others to recognize. Other users can see your nicknames but cannot change them.

Nicknames are stored in each hyperdrive inside /.well-known/host-meta.json under the name key, as specified in RFC6415.

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5.3.3 Petnames

Petnames are locally unique hyperdrive identifiers. You can give a petname to any hyperdrive you load, whether you created it or not.

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5.3.4 Seeds

Seeds are used in tandem with your secret master key (see Master key) to generate public keys (see Public keys). The same seed and master key will always produce the same public key, so a hyperdrive’s seed cannot be changed. Seeds are local but not secret. To share a drive, you must use a public key or DNS domain (see DNS domains).

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5.3.5 DNS domains

It is possible to use DNSLink to link to a hyperdrive with a domain name instead of a public key (see Public keys), like hyper://example.org/path/to/file. Create a TXT record at _dnslink.example.org with the contents /hyper/PUBLIC-KEY (no trailing slash). Note: relying on DNS adds another point of centralization, reducing the durability of your link. hyperdrive.el somewhat mitigates this issue by remembering which public key the DNS record resolved to, so that peers can use the stored public key itself for subsequent connections.

DNS domains are checked for suspicious characters (see (elisp)Suspicious Text).

6 Customization

You can adjust the following options in the customization interface by running M-x customize-group RET hyperdrive RET:

User Option: hyperdrive-gateway-program

Name of executable to run when starting the gateway with hyperdrive-gateway-start-function. hyperdrive-install will install the gateway to this file in hyperdrive-gateway-directory.

User Option: hyperdrive-gateway-directory

Filesystem directory in which the gateway is expected to be found. hyperdrive-install will install the gateway to this location. When starting the gateway, if hyperdrive-gateway-program is not found in this directory, Emacs searches PATH for hyperdrive-gateway-program.

User Option: hyperdrive-gateway-command-args

Command line arguments passed to the gateway when starting the gateway with the default hyperdrive-gateway-start-function.

User Option: hyperdrive-gateway-port

hyperdrive.el will send HTTP requests to the gateway on this port. Defaults to 4973. The default hyperdrive-gateway-start-function will start the gateway on this port.

User Option: hyperdrive-persist-location

Location where persist will store data, currently hyperdrive-hyperdrives and hyperdrive-version-ranges. By default, uses the default persist location.

User Option: hyperdrive-timestamp-format

Format string used for timestamps. Passed to format-time-string, which see.

User Option: hyperdrive-queue-limit

Default number of request sent to the gateway at a time in a queue. Defaults to 20.

User Option: hyperdrive-fill-version-ranges-limit

Default maximum number of requests when filling version history. Defaults to 100.

User Option: hyperdrive-preferred-formats

List of metadata types used to display hyperdrives. Hyperdrives are displayed using the first available metadata type. See Naming section for what this means.

User Option: hyperdrive-default-entry-format

Format string for displaying hyperdrive entries (files/directories). By default, entries are displayed with the preferred hyperdrive format in brackets (see hyperdrive-preferred-formats), followed by the full entry path, followed by “version: ” and version in parentheses.

User Option: hyperdrive-buffer-name-format

Format string for buffer names of buffers visiting hyperdrive files/directories. By default, this format is like hyperdrive-default-entry-format with the entry name sans directory instead of the full path.

User Option: hyperdrive-formats

Alist mapping hyperdrive and hyperdrive entry metadata to a format string, used in hyperdrive-default-entry-format and hyperdrive-buffer-name-format as well as other places hyperdrives or entries are displayed. By default, each metadatum is prefixed by its type, e.g., the petname foo is displayed by default as petname:foo.

Feel free to adjust the following example configuration for abbreviated labels:

(setq hyperdrive-formats
      '((name . "%s")
        (version . " (%s)")
        (path . "%s")
        (petname . "p:%s")
        (nickname . "n:%s")
        (public-key . "k:%s")
        (short-key . "k:%.8s…")
        (seed . "s:%s")
        (domains . "d:%s")))

With this snippet, the petname foo now displays as p:foo. For further customization, run M-x customize-group RET hyperdrive-entry-format.

6.1 Additional customization

This section mentions ways to change the behavior of hyperdrive.el besides its own customization options.

6.1.1 Completion styles and cycling

hyperdrive-complete-hyperdrive offers a completing-read interface for selecting a hyperdrive from a list of known hyperdrive. You can customize the completion styles and cycling behavior of hyperdrive-complete-hyperdrive by customizing the hyperdrive category in completion-category-overrides.

7 Known limitations

7.1 No empty directories

Instead of files and folders, Hyperdrive technically has entries and entry prefixes. In other words, folders don’t exist unless they contain files. This results in potentially unexpected behavior:

  • it is not possible to create empty directories
  • deleting the last file in a folder deletes the folder as well

When a hyperdrive file or folder is not found, hyperdrive.el prompts you for an action (see Unknown paths).

7.2 Files and folders can have the same name

In the current implementation of Hyperdrive, it’s possible for an entry (folder) and an entry prefix (folder) to have the same name, e.g., hyper://PUBLIC-KEY/foo/bar/ and hyper://PUBLIC-KEY/foo/bar. In this case, the folder listing for hyper://PUBLIC-KEY/foo/ would display the bar entry but not the bar/ entry prefix.

8 Tips

Up: Tips   [Contents][Index]

8.1 Quick documentation access

There are many ways to read this info manual within Emacs:

Command: hyperdrive-info-manual

Open the hyperdrive.el info manual.

You can also open the hyperdrive.el info manual from hyperdrive-menu by pressing ? twice.

To view documentation for particular hyperdrive.el commands, functions, and variables, press C-h o (describe-symbol). Inside the *Help* buffer that pops open, you can press i (help-goto-info) to jump to the relevant section in the hyperdrive.el manual.

9 Troubleshooting

9.1 Reinstall/upgrade the gateway

Please ensure that you have the expected version of the gateway by running M-x hyperdrive-install.

10 Contributing/Getting help

You’re welcome to join our public XMPP chat room!

Bugs can be submitted to the ushin issue tracker. Patches, comments or questions can be submitted to the ushin public inbox.

11 Uninstallation

If you have installed the gateway with hyperdrive-install, you can delete the gateway which Emacs downloaded according to the values of hyperdrive-gateway-directory and hyperdrive-gateway-program, which is ~/.local/lib/hyperdrive.el/hyper-gateway-ushin by default.

You can delete the user data which hyper-gateway-ushin stores by default in ~/.local/share/hyper-gateway-nodejs.

You can remove hyperdrive.el with M-x package-delete hyperdrive.

12 Acknowledgments

Adam Porter for rewriting hyperdrive.el and for his work on plz.el.

Mauve Signweaver for their guidance into the world of p2p as well as the development of hyper-gateway.

Jonas Bernoulli for improving hyperdrive-mirror and for his work on transient.el.

Protesilaos Stavrou for design input and user-testing hyperdrive.el.

Ihor Radchenko for guidance about security and Org mode integration.

Karl Voit for his feedback which inspired the design of hyperdrive-mirror.

Steve Purcell and Akira Komamura for suggestions to improve our CI build manifests.

Eshel Yaron for the suggestion to add hyperdrive-menu-bar-mode.

13 Indices

13.1 Keystroke index

Previous: , Up: Indices   [Contents][Index]

13.4 Concept index

Jump to:   D   H   N   P   S   V  
Index Entry  Section

DNS domains: DNS domains

hyper-gateway-ushin: hyper-gateway-ushin

Naming: Naming
Nicknames: Nicknames

Petnames: Petnames
Public keys: Public keys

Seeds: Seeds
Sparse replication: Sparse replication

Versioning: Versioning

Jump to:   D   H   N   P   S   V  

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