--- emacs/lisp/emacs-lisp/package.el	2021-08-13 19:52:44.647493393 +0200
+++ package.el	2021-08-20 23:13:36.621235559 +0200
@@ -396,6 +396,15 @@
   :version "25.1"
   :type '(repeat symbol))
 
+(defcustom package-install-local-multifile-packages-symlinked t
+  "Non-nil means to place a symlink to original package directory location in
+`package-user-dir' reather then copy files to a subfolder of
+  `package-user-dir'.  This option is meant for pacakge developers rather than
+  ordinary users."
+  :type '(boolean)
+  :risky t
+  :version "28.1")
+
 (defcustom package-native-compile nil
   "Non-nil means to native compile packages on installation."
   :type '(boolean)
@@ -954,19 +963,22 @@
          (pkg-dir (expand-file-name dirname package-user-dir)))
     (pcase (package-desc-kind pkg-desc)
       ('dir
-       (make-directory pkg-dir t)
-       (let ((file-list
-              (directory-files
-               default-directory 'full "\\`[^.].*\\.el\\'" 'nosort)))
-         (dolist (source-file file-list)
-           (let ((target-el-file
-                  (expand-file-name (file-name-nondirectory source-file) pkg-dir)))
-             (copy-file source-file target-el-file t)))
-         ;; Now that the files have been installed, this package is
-         ;; indistinguishable from a `tar' or a `single'. Let's make
-         ;; things simple by ensuring we're one of them.
-         (setf (package-desc-kind pkg-desc)
-               (if (> (length file-list) 1) 'tar 'single))))
+       (if package-install-local-multifile-packages-symlinked
+           (make-symbolic-link (expand-file-name default-directory) pkg-dir t)
+         (progn
+           (make-directory pkg-dir t)
+           (let ((file-list
+                  (directory-files
+                   default-directory 'full "\\`[^.].*\\.el\\'" 'nosort)))
+             (dolist (source-file file-list)
+               (let ((target-el-file
+                      (expand-file-name (file-name-nondirectory source-file) pkg-dir)))
+                 (copy-file source-file target-el-file t)))
+             ;; Now that the files have been installed, this package is
+             ;; indistinguishable from a `tar' or a `single'. Let's make
+             ;; things simple by ensuring we're one of them.
+             (setf (package-desc-kind pkg-desc)
+                   (if (> (length file-list) 1) 'tar 'single))))))
       ('tar
        (make-directory package-user-dir t)
        (let* ((default-directory (file-name-as-directory package-user-dir)))