You can install org-roam from MELPA or MELPA Stable using package.el:

M-x package-install RET org-roam RET

Here's a very basic sample for configuration of org-roam using use-package:

(use-package org-roam
  :ensure t
  :custom
  (org-roam-directory (file-truename "/path/to/org-files/"))
  :bind (("C-c n l" . org-roam-buffer-toggle)
         ("C-c n f" . org-roam-node-find)
         ("C-c n g" . org-roam-graph)
         ("C-c n i" . org-roam-node-insert)
         ("C-c n c" . org-roam-capture)
         ;; Dailies
         ("C-c n j" . org-roam-dailies-capture-today))
  :config
  (org-roam-db-autosync-mode)
  ;; If using org-roam-protocol
  (require 'org-roam-protocol))

Note that the file-truename function is only necessary when you use symbolic link to org-roam-directory. Org-roam won't automatically resolve symbolic link to the directory.

Installation from MELPA or MELPA Stable using straight.el:

(straight-use-package 'org-roam)

Or with use-package:

(use-package org-roam
  :straight t
  ...)

If you need to install the package directly from the source repository, instead of from MELPA, the next sample shows how to do so:

(use-package org-roam
  :straight (:host github :repo "org-roam/org-roam"
             :files (:defaults "extensions/*"))
  ...)

If you plan to use your own local fork for the development and contribution, the next sample will get you there:

(use-package org-roam
  :straight (:local-repo "/path/to/org-roam-fork"
             :files (:defaults "extensions/*")
             :build (:not compile))
  ...)

Doom's :lang org module comes with support for org-roam, but it's not enabled by default. To activate it pass +roam2 flag to org module in your $DOOMDIR/init.el (e.g. (org +roam2)), save the file and run doom sync -u in your shell.

To provide better stability, Doom pins the package to a specific commit. If you need to unpin it (not recommended doing that, request Doom to bump the package instead) use the next in your packages.el:

(unpin! org-roam)

If for some reasons you want to use a different recipe for org-roam, you can use the next form in your packages.el to install the package from a recipe repository (e.g. MELPA):

(package! org-roam)

You can pass :pin "commit hash" to pin the package to a specific commit.

With the next sample you can install the package directly from the source repository:

(package! org-roam
  :recipe (:host github :repo "org-roam/org-roam"
           :files (:defaults "extensions/*")))

And if you plan to use your own local fork for the development or contribution, the next sample will get you there:

(package! org-roam
  :recipe (:local-repo "/path/to/org-roam-fork"
           :files (:defaults "extensions/*")
           :build (:not compile)))

To install the package without using a package manager you have the next two options:

1. Install the package by cloning it with git from the source repository.
2. Or install the package by downloading the latest release version.

In both of the cases you will need to ensure that you have all the required dependencies. These include:

• dash
• f
• s
• org (9.4 is the minimal required version!)
• emacsql
• emacsql-sqlite
• magit-section
• filenotify-recursive

After installing the package, you will need to properly setup load-path to the package:

(add-to-list 'load-path "/path/to/org-roam/")
(add-to-list 'load-path "/path/to-org-roam/extensions/")

After which you should be able to resolve (require 'org-roam) call without any problems.

Org-roam also comes with .texi files to integrate with Emacs' built-in Info system. Read the manual to find more details for how to install them manually.