diff --git a/core/core-configuration-layer.el b/core/core-configuration-layer.el
index 6a1bff09a..a61f078bd 100644
--- a/core/core-configuration-layer.el
+++ b/core/core-configuration-layer.el
@@ -85,7 +85,7 @@ LAYER has to be installed for this method to work properly."
   (delq nil (mapcar
              (lambda (x)
                (let ((pkg (object-assoc x :name configuration-layer--packages)))
-                 (when (and pkg (eq (oref layer :name) (oref pkg :owner)))
+                 (when (and pkg (eq (oref layer :name) (car (oref pkg :owners))))
                    pkg)))
              (oref layer :packages))))
 
@@ -97,10 +97,10 @@ LAYER has to be installed for this method to work properly."
   ((name :initarg :name
          :type symbol
          :documentation "Name of the package.")
-   (owner :initarg :owner
-          :initform nil
-          :type symbol
-          :documentation "The layer defining the init function.")
+   (owners :initarg :owners
+           :initform nil
+           :type list
+           :documentation "The layer defining the init function.")
    (pre-layers :initarg :pre-layers
                :initform '()
                :type list
@@ -466,7 +466,8 @@ If TOGGLEP is non nil then `:toggle' parameter is ignored."
                    configuration-layer--packages)))))
   (let* ((pkg (object-assoc pkg-symbol
                             :name (or pkg-list configuration-layer--packages)))
-         (owner (oref pkg :owner)))
+         (owners (oref pkg :owners))
+         (owner (car owners)))
     (with-help-window (help-buffer)
       ;; declaration location
       (princ pkg-symbol)
@@ -656,14 +657,14 @@ If TOGGLEP is non nil then `:toggle' parameter is ignored."
             (when ownerp
               ;; last owner wins over the previous one,
               ;; still warn about mutliple owners
-              (when (and (oref obj :owner)
-                         (not (eq layer-name (oref obj :owner))))
+              (when (and (oref obj :owners)
+                         (not (memq layer-name (oref obj :owners))))
                 (spacemacs-buffer/warning
                  (format (concat "More than one init function found for "
                                  "package %S. Previous owner was %S, "
                                  "replacing it with layer %S.")
-                         pkg-name (oref obj :owner) layer-name)))
-              (oset obj :owner layer-name))
+                         pkg-name (car (oref obj :owners)) layer-name)))
+              (push layer-name (oref obj :owners)))
             ;; if no function at all is found for the package, then check
             ;; again this layer later to resolve `package-usedp'  usage in
             ;; `packages.el' files
@@ -701,7 +702,7 @@ If TOGGLEP is non nil then `:toggle' parameter is ignored."
             (setq obj (configuration-layer/make-package pkg obj t))
           (setq obj (configuration-layer/make-package pkg nil t))
           (push obj configuration-layer--packages)
-          (oset obj :owner 'dotfile))))
+          (push 'dotfile (oref obj :owners)))))
     (dolist (xpkg dotspacemacs-excluded-packages)
       (let ((obj (object-assoc xpkg :name configuration-layer--packages)))
         (unless obj
@@ -731,12 +732,12 @@ If TOGGLEP is non nil then `:toggle' parameter is ignored."
         (let* ((layer (object-assoc layer-name
                                     :name configuration-layer--layers))
                (packages (when layer (cfgl-layer-owned-packages layer))))
-          ;; set lazy install flag for a layer if and only if all its owned
-          ;; distant packages are not already installed
+          ;; set lazy install flag for a layer if and only if its owned
+          ;; distant packages are all not already installed
           (let ((lazy (cl-reduce
                        (lambda (x y) (and x y))
                        (mapcar (lambda (p)
-                                 (or (not (eq layer-name (oref p :owner)))
+                                 (or (not (eq layer-name (car (oref p :owners))))
                                      (null (package-installed-p
                                             (oref p :name)))))
                                (configuration-layer//get-distant-packages
@@ -779,7 +780,7 @@ return both used and unused packages."
               (and (not (memq (oref x :location) '(built-in site local)))
                    (not (stringp (oref x :location)))
                    (or (null usedp)
-                       (and (not (null (oref x :owner)))
+                       (and (not (null (oref x :owners)))
                             (cfgl-package-enabledp x)
                             (not (oref x :excluded))))))))
 
@@ -984,7 +985,7 @@ path."
   "Return non-nil if NAME is the name of a used package."
   (let ((obj (object-assoc name :name configuration-layer--packages)))
     (when (and obj (not (oref obj :excluded)))
-      (not (null (oref obj :owner))))))
+      (not (null (oref obj :owners))))))
 
 (defun  configuration-layer/package-lazy-installp (name)
   "Return non-nil if NAME is the name of a package to be lazily installed."
@@ -1040,7 +1041,7 @@ path."
 
 (defun configuration-layer//install-package (pkg)
   "Unconditionally install the package PKG."
-  (let* ((layer (when pkg (oref pkg :owner)))
+  (let* ((layer (when pkg (car (oref pkg :owners))))
          (location (when pkg (oref pkg :location))))
     (spacemacs-buffer/replace-last-line
      (format "--> installing %s: %s%s... [%s/%s]"
@@ -1156,7 +1157,7 @@ path."
 (defun configuration-layer//install-from-recipe (pkg)
   "Install PKG from a recipe."
   (let* ((pkg-name (oref pkg :name))
-         (layer (oref pkg :owner))
+         (layer (car (oref pkg :owners)))
          (recipe (cons pkg-name (cdr (oref pkg :location)))))
     (if recipe
         (quelpa recipe)
@@ -1260,7 +1261,7 @@ path."
              (not (oref pkg :protected)))
         (spacemacs-buffer/message
          (format "%S ignored since it has been excluded." pkg-name)))
-       ((null (oref pkg :owner))
+       ((null (oref pkg :owners))
         (spacemacs-buffer/message
          (format "%S ignored since it has no owner layer." pkg-name)))
        ((not (cfgl-package-enabledp pkg))
@@ -1276,13 +1277,13 @@ path."
                "Location path for package %S does not exists (value: %s)."
                pkg location)))
            ((and (eq 'local location)
-                 (eq 'dotfile (oref pkg :owner)))
+                 (eq 'dotfile (car (oref pkg :owners))))
             (push (file-name-as-directory
                    (concat configuration-layer-private-directory "local/"
                            (symbol-name (oref pkg :name))))
                   load-path))
            ((eq 'local location)
-            (let* ((owner (object-assoc (oref pkg :owner)
+            (let* ((owner (object-assoc (car (oref pkg :owners))
                                         :name configuration-layer--layers))
                    (dir (when owner (oref owner :dir))))
               (push (format "%slocal/%S/" dir pkg-name) load-path)))))
@@ -1290,7 +1291,7 @@ path."
         (unless (memq (oref pkg :location) '(local site built-in))
           (configuration-layer//activate-package pkg-name))
         (cond
-         ((eq 'dotfile (oref pkg :owner))
+         ((eq 'dotfile (car (oref pkg :owners)))
           (spacemacs-buffer/message
            (format "%S is configured in the dotfile." pkg-name)))
          (t
@@ -1299,7 +1300,7 @@ path."
 (defun configuration-layer//configure-package (pkg)
   "Configure PKG."
   (let* ((pkg-name (oref pkg :name))
-         (owner (oref pkg :owner))
+         (owner (car (oref pkg :owners)))
          (owner-layer (object-assoc owner :name configuration-layer--layers))
          (disabled-for-layers (oref owner-layer :disabled-for)))
     (spacemacs-buffer/message (format "Configuring %S..." pkg-name))
diff --git a/tests/core/core-configuration-layer-utest.el b/tests/core/core-configuration-layer-utest.el
index 647516efc..c19bedfc3 100644
--- a/tests/core/core-configuration-layer-utest.el
+++ b/tests/core/core-configuration-layer-utest.el
@@ -9,6 +9,7 @@
 ;;
 ;;; License: GPLv3
 (require 'mocker)
+(require 'core-command-line)
 (require 'core-configuration-layer)
 
 ;; ---------------------------------------------------------------------------
@@ -20,12 +21,12 @@
                             :name 'layer1
                             :packages '(pkg1 pkg2 pkg3 pkg4)))
         (configuration-layer--packages
-         (list (cfgl-package "pkg1" :name 'pkg1 :owner 'layer2)
-               (cfgl-package "pkg2" :name 'pkg2 :owner 'layer1)
-               (cfgl-package "pkg3" :name 'pkg3 :owner 'layer1)
-               (cfgl-package "pkg4" :name 'pkg4 :owner 'layer2))))
-    (should (equal (list (cfgl-package "pkg2" :name 'pkg2 :owner 'layer1)
-                         (cfgl-package "pkg3" :name 'pkg3 :owner 'layer1))
+         (list (cfgl-package "pkg1" :name 'pkg1 :owners '(layer2))
+               (cfgl-package "pkg2" :name 'pkg2 :owners '(layer1))
+               (cfgl-package "pkg3" :name 'pkg3 :owners '(layer1))
+               (cfgl-package "pkg4" :name 'pkg4 :owners '(layer2)))))
+    (should (equal (list (cfgl-package "pkg2" :name 'pkg2 :owners '(layer1))
+                         (cfgl-package "pkg3" :name 'pkg3 :owners '(layer1)))
                    (cfgl-layer-owned-packages layer1)))))
 
 (ert-deftest test-cfgl-layer-owned-packages--nil-layer-returns-nil ()
@@ -243,7 +244,7 @@
          (expected (cfgl-package "testpkg"
                                  :name 'testpkg
                                  :location 'elpa
-                                 :owner nil
+                                 :owners nil
                                  :pre-layers nil
                                  :post-layers nil
                                  :step nil
@@ -255,7 +256,7 @@
   (let* ((input '(testpkg :location local :step pre))
          (expected (cfgl-package "testpkg"
                                  :name 'testpkg
-                                 :owner nil
+                                 :owners nil
                                  :location 'local
                                  :pre-layers nil
                                  :post-layers nil
@@ -267,14 +268,14 @@
 (ert-deftest test-make-package--copy-package-properties-to-passed-obj ()
   (let* ((obj (cfgl-package "testpkg"
                             :name 'testpkg
-                            :owner nil
+                            :owners nil
                             :location 'elpa
                             :step nil
                             :excluded t))
          (pkg '(testpkg :location local :step pre :excluded nil))
          (expected (cfgl-package "testpkg"
                                  :name 'testpkg
-                                 :owner nil
+                                 :owners nil
                                  :location 'local
                                  :step 'pre
                                  :excluded nil))
@@ -286,49 +287,49 @@
 ;; ---------------------------------------------------------------------------
 
 (defvar test-get-distant-packages--test-data
-  `(,(cfgl-package "pkg18" :name 'pkg18 :owner nil)
-    ,(cfgl-package "pkg17" :name 'pkg17 :owner nil :location 'elpa)
-    ,(cfgl-package "pkg16" :name 'pkg16 :owner nil :toggle nil)
-    ,(cfgl-package "pkg15" :name 'pkg15 :owner nil :toggle t)
-    ,(cfgl-package "pkg14" :name 'pkg14 :owner nil :location '(recipe))
-    ,(cfgl-package "pkg13" :name 'pkg13 :owner nil :location 'built-in)
-    ,(cfgl-package "pkg12" :name 'pkg12 :owner nil :location 'local)
-    ,(cfgl-package "pkg11" :name 'pkg11 :owner nil :location 'site)
-    ,(cfgl-package "pkg10" :name 'pkg10 :owner nil :location "/path")
-    ,(cfgl-package "pkg9" :name 'pkg9 :owner 'layer)
-    ,(cfgl-package "pkg8" :name 'pkg8 :owner 'layer :location 'elpa)
-    ,(cfgl-package "pkg7" :name 'pkg7 :owner 'layer :toggle nil)
-    ,(cfgl-package "pkg6" :name 'pkg6 :owner 'layer :toggle t)
-    ,(cfgl-package "pkg5" :name 'pkg5 :owner 'layer :location '(recipe))
-    ,(cfgl-package "pkg4" :name 'pkg4 :owner 'layer :location 'built-in)
-    ,(cfgl-package "pkg3" :name 'pkg3 :owner 'layer :location 'local)
-    ,(cfgl-package "pkg2" :name 'pkg2 :owner 'layer :location 'site)
-    ,(cfgl-package "pkg1" :name 'pkg1 :owner 'layer :location "/path")))
+  `(,(cfgl-package "pkg18" :name 'pkg18 :owners nil)
+    ,(cfgl-package "pkg17" :name 'pkg17 :owners nil :location 'elpa)
+    ,(cfgl-package "pkg16" :name 'pkg16 :owners nil :toggle nil)
+    ,(cfgl-package "pkg15" :name 'pkg15 :owners nil :toggle t)
+    ,(cfgl-package "pkg14" :name 'pkg14 :owners nil :location '(recipe))
+    ,(cfgl-package "pkg13" :name 'pkg13 :owners nil :location 'built-in)
+    ,(cfgl-package "pkg12" :name 'pkg12 :owners nil :location 'local)
+    ,(cfgl-package "pkg11" :name 'pkg11 :owners nil :location 'site)
+    ,(cfgl-package "pkg10" :name 'pkg10 :owners nil :location "/path")
+    ,(cfgl-package "pkg9" :name 'pkg9 :owners '(layer))
+    ,(cfgl-package "pkg8" :name 'pkg8 :owners '(layer) :location 'elpa)
+    ,(cfgl-package "pkg7" :name 'pkg7 :owners '(layer) :toggle nil)
+    ,(cfgl-package "pkg6" :name 'pkg6 :owners '(layer) :toggle t)
+    ,(cfgl-package "pkg5" :name 'pkg5 :owners '(layer) :location '(recipe))
+    ,(cfgl-package "pkg4" :name 'pkg4 :owners '(layer) :location 'built-in)
+    ,(cfgl-package "pkg3" :name 'pkg3 :owners '(layer) :location 'local)
+    ,(cfgl-package "pkg2" :name 'pkg2 :owners '(layer) :location 'site)
+    ,(cfgl-package "pkg1" :name 'pkg1 :owners '(layer) :location "/path")))
 
 (ert-deftest test-get-distant-packages--return-only-used-packages ()
   (let ((packages test-get-distant-packages--test-data))
     (should
      (equal
-      `(,(cfgl-package "pkg9" :name 'pkg9 :owner 'layer)
-        ,(cfgl-package "pkg8" :name 'pkg8 :owner 'layer :location 'elpa)
-        ,(cfgl-package "pkg6" :name 'pkg6 :owner 'layer :toggle t)
-        ,(cfgl-package "pkg5" :name 'pkg5 :owner 'layer :location '(recipe)))
+      `(,(cfgl-package "pkg9" :name 'pkg9 :owners '(layer))
+        ,(cfgl-package "pkg8" :name 'pkg8 :owners '(layer) :location 'elpa)
+        ,(cfgl-package "pkg6" :name 'pkg6 :owners '(layer) :toggle t)
+        ,(cfgl-package "pkg5" :name 'pkg5 :owners '(layer) :location '(recipe)))
       (configuration-layer//get-distant-packages packages t)))))
 
 (ert-deftest test-get-distant-packages--return-only-unused-packages ()
   (let ((packages test-get-distant-packages--test-data))
     (should
      (equal
-      `(,(cfgl-package "pkg18" :name 'pkg18 :owner nil)
-        ,(cfgl-package "pkg17" :name 'pkg17 :owner nil :location 'elpa)
-        ,(cfgl-package "pkg16" :name 'pkg16 :owner nil :toggle nil)
-        ,(cfgl-package "pkg15" :name 'pkg15 :owner nil :toggle t)
-        ,(cfgl-package "pkg14" :name 'pkg14 :owner nil :location '(recipe))
-        ,(cfgl-package "pkg9" :name 'pkg9 :owner 'layer)
-        ,(cfgl-package "pkg8" :name 'pkg8 :owner 'layer :location 'elpa)
-        ,(cfgl-package "pkg7" :name 'pkg7 :owner 'layer :toggle nil)
-        ,(cfgl-package "pkg6" :name 'pkg6 :owner 'layer :toggle t)
-        ,(cfgl-package "pkg5" :name 'pkg5 :owner 'layer :location '(recipe)))
+      `(,(cfgl-package "pkg18" :name 'pkg18 :owners nil)
+        ,(cfgl-package "pkg17" :name 'pkg17 :owners nil :location 'elpa)
+        ,(cfgl-package "pkg16" :name 'pkg16 :owners nil :toggle nil)
+        ,(cfgl-package "pkg15" :name 'pkg15 :owners nil :toggle t)
+        ,(cfgl-package "pkg14" :name 'pkg14 :owners nil :location '(recipe))
+        ,(cfgl-package "pkg9" :name 'pkg9 :owners '(layer))
+        ,(cfgl-package "pkg8" :name 'pkg8 :owners '(layer) :location 'elpa)
+        ,(cfgl-package "pkg7" :name 'pkg7 :owners '(layer) :toggle nil)
+        ,(cfgl-package "pkg6" :name 'pkg6 :owners '(layer) :toggle t)
+        ,(cfgl-package "pkg5" :name 'pkg5 :owners '(layer) :location '(recipe)))
       (configuration-layer//get-distant-packages packages nil)))))
 
 ;; ---------------------------------------------------------------------------
@@ -348,9 +349,9 @@
       (load (f) ((:output nil :occur 1))))
      (let (configuration-layer--packages)
        (configuration-layer/get-packages layers)
-       (should (equal (list (cfgl-package "pkg3" :name 'pkg3 :owner 'layer1)
-                            (cfgl-package "pkg2" :name 'pkg2 :owner 'layer1)
-                            (cfgl-package "pkg1" :name 'pkg1 :owner 'layer1))
+       (should (equal (list (cfgl-package "pkg3" :name 'pkg3 :owners '(layer1))
+                            (cfgl-package "pkg2" :name 'pkg2 :owners '(layer1))
+                            (cfgl-package "pkg1" :name 'pkg1 :owners '(layer1)))
                       configuration-layer--packages))))))
 
 (ert-deftest test-get-packages--lists-only ()
@@ -368,9 +369,9 @@
       (load (f) ((:output nil :occur 1))))
      (let (configuration-layer--packages)
        (configuration-layer/get-packages layers)
-       (should (equal (list (cfgl-package "pkg3" :name 'pkg3 :owner 'layer1 :location 'local :step 'pre)
-                            (cfgl-package "pkg2" :name 'pkg2 :owner 'layer1 :location '(recipe blahblah))
-                            (cfgl-package "pkg1" :name 'pkg1 :owner 'layer1 :excluded t))
+       (should (equal (list (cfgl-package "pkg3" :name 'pkg3 :owners '(layer1) :location 'local :step 'pre)
+                            (cfgl-package "pkg2" :name 'pkg2 :owners '(layer1) :location '(recipe blahblah))
+                            (cfgl-package "pkg1" :name 'pkg1 :owners '(layer1) :excluded t))
                       configuration-layer--packages))))))
 
 (ert-deftest test-get-packages--symbols-and-lists ()
@@ -390,10 +391,10 @@
       (load (f) ((:output nil :occur 1))))
      (let (configuration-layer--packages)
        (configuration-layer/get-packages layers)
-       (should (equal (list (cfgl-package "pkg4" :name 'pkg4 :owner 'layer1)
-                            (cfgl-package "pkg3" :name 'pkg3 :owner 'layer1 :location 'local :step 'pre)
-                            (cfgl-package "pkg2" :name 'pkg2 :owner 'layer1 :location '(recipe blahblah))
-                            (cfgl-package "pkg1" :name 'pkg1 :owner 'layer1))
+       (should (equal (list (cfgl-package "pkg4" :name 'pkg4 :owners '(layer1))
+                            (cfgl-package "pkg3" :name 'pkg3 :owners '(layer1) :location 'local :step 'pre)
+                            (cfgl-package "pkg2" :name 'pkg2 :owners '(layer1) :location '(recipe blahblah))
+                            (cfgl-package "pkg1" :name 'pkg1 :owners '(layer1)))
                       configuration-layer--packages))))))
 
 (ert-deftest test-get-packages--pkg2-has-no-owner-because-no-init-function ()
@@ -405,12 +406,13 @@
     (defun layer2/init-pkg3 nil)
     (mocker-let
      ((file-exists-p (f) ((:output t :occur 1)))
+      (spacemacs-buffer/warning (m) ((:output nil)))
       (load (f) ((:output nil :occur 1))))
      (let (configuration-layer--packages)
        (configuration-layer/get-packages layers)
-       (should (equal (list (cfgl-package "pkg3" :name 'pkg3 :owner 'layer2)
+       (should (equal (list (cfgl-package "pkg3" :name 'pkg3 :owners '(layer2))
                             (cfgl-package "pkg2" :name 'pkg2)
-                            (cfgl-package "pkg1" :name 'pkg1 :owner 'layer2))
+                            (cfgl-package "pkg1" :name 'pkg1 :owners '(layer2)))
                       configuration-layer--packages))))))
 
 (ert-deftest test-get-packages--pre-init-function ()
@@ -427,7 +429,7 @@
       (load (f) ((:output nil :occur 2))))
      (let (configuration-layer--packages)
        (configuration-layer/get-packages layers)
-       (should (equal (list (cfgl-package "pkg1" :name 'pkg1 :owner 'layer3 :pre-layers '(layer4)))
+       (should (equal (list (cfgl-package "pkg1" :name 'pkg1 :owners '(layer3) :pre-layers '(layer4)))
                       configuration-layer--packages))))))
 
 (ert-deftest test-get-packages--post-init-function ()
@@ -444,7 +446,7 @@
       (load (f) ((:output nil :occur 2))))
      (let (configuration-layer--packages)
        (configuration-layer/get-packages layers)
-       (should (equal (list (cfgl-package "pkg1" :name 'pkg1 :owner 'layer3 :post-layers '(layer5)))
+       (should (equal (list (cfgl-package "pkg1" :name 'pkg1 :owners '(layer3) :post-layers '(layer5)))
                       configuration-layer--packages))))))
 
 (ert-deftest test-get-packages--pre-and-post-init-functions ()
@@ -462,7 +464,7 @@
       (load (f) ((:output nil :occur 2))))
      (let (configuration-layer--packages)
        (configuration-layer/get-packages layers)
-       (should (equal (list (cfgl-package "pkg1" :name 'pkg1 :owner 'layer3 :pre-layers '(layer6) :post-layers '(layer6)))
+       (should (equal (list (cfgl-package "pkg1" :name 'pkg1 :owners '(layer3) :pre-layers '(layer6) :post-layers '(layer6)))
                       configuration-layer--packages))))))
 
 (ert-deftest test-get-packages--several-init-functions-last-one-is-the-owner ()
@@ -480,7 +482,9 @@
       (spacemacs-buffer/warning (msg &rest args) ((:output nil :occur 1))))
      (let (configuration-layer--packages)
        (configuration-layer/get-packages layers)
-       (should (equal (list (cfgl-package "pkg1" :name 'pkg1 :owner 'layer8))
+       (should (equal (list (cfgl-package "pkg1"
+                                          :name 'pkg1
+                                          :owners '(layer8 layer7)))
                       configuration-layer--packages))))))
 
 (ert-deftest test-get-packages--layer-10-excludes-pkg2-in-layer-9 ()
@@ -498,9 +502,9 @@
       (load (f) ((:output nil :occur 2))))
      (let (configuration-layer--packages)
        (configuration-layer/get-packages layers)
-       (should (equal (list (cfgl-package "pkg3" :name 'pkg3 :owner 'layer10)
-                            (cfgl-package "pkg2" :name 'pkg2 :owner 'layer9 :excluded t)
-                            (cfgl-package "pkg1" :name 'pkg1 :owner 'layer9))
+       (should (equal (list (cfgl-package "pkg3" :name 'pkg3 :owners '(layer10))
+                            (cfgl-package "pkg2" :name 'pkg2 :owners '(layer9) :excluded t)
+                            (cfgl-package "pkg1" :name 'pkg1 :owners '(layer9)))
                       configuration-layer--packages))))))
 
 (ert-deftest test-get-packages--dotfile-excludes-pkg2-in-layer-11 ()
@@ -517,9 +521,9 @@
       (load (f) ((:output nil :occur 1))))
      (let (configuration-layer--packages)
        (configuration-layer/get-packages layers t)
-       (should (equal (list (cfgl-package "pkg3" :name 'pkg3 :owner 'layer11)
-                            (cfgl-package "pkg2" :name 'pkg2 :owner 'layer11 :excluded t)
-                            (cfgl-package "pkg1" :name 'pkg1 :owner 'layer11))
+       (should (equal (list (cfgl-package "pkg3" :name 'pkg3 :owners '(layer11))
+                            (cfgl-package "pkg2" :name 'pkg2 :owners '(layer11) :excluded t)
+                            (cfgl-package "pkg1" :name 'pkg1 :owners '(layer11)))
                       configuration-layer--packages))))))
 
 (ert-deftest test-get-packages--dotfile-declares-and-owns-one-additional-package ()
@@ -535,9 +539,9 @@
       (load (f) ((:output nil :occur 1))))
      (let (configuration-layer--packages)
        (configuration-layer/get-packages layers t)
-       (should (equal (list (cfgl-package "pkg3" :name 'pkg3 :owner 'dotfile)
-                            (cfgl-package "pkg2" :name 'pkg2 :owner 'layer12)
-                            (cfgl-package "pkg1" :name 'pkg1 :owner 'layer12))
+       (should (equal (list (cfgl-package "pkg3" :name 'pkg3 :owners '(dotfile))
+                            (cfgl-package "pkg2" :name 'pkg2 :owners '(layer12))
+                            (cfgl-package "pkg1" :name 'pkg1 :owners '(layer12)))
                       configuration-layer--packages))))))
 
 (ert-deftest test-get-packages--last-owner-can-overwrite-location ()
@@ -555,7 +559,10 @@
       (spacemacs-buffer/warning (msg &rest args) ((:output nil :occur 1))))
      (let (configuration-layer--packages)
        (configuration-layer/get-packages layers)
-       (should (equal (list (cfgl-package "pkg1" :name 'pkg1 :owner 'layer14 :location 'local))
+       (should (equal (list (cfgl-package "pkg1"
+                                          :name 'pkg1
+                                          :owners '(layer14 layer13)
+                                          :location 'local))
                       configuration-layer--packages))))))
 
 (ert-deftest test-get-packages--last-owner-can-overwrite-step-nil-to-pre ()
@@ -573,7 +580,10 @@
       (spacemacs-buffer/warning (msg &rest args) ((:output nil :occur 1))))
      (let (configuration-layer--packages)
        (configuration-layer/get-packages layers)
-       (should (equal (list (cfgl-package "pkg1" :name 'pkg1 :owner 'layer16 :step 'pre))
+       (should (equal (list (cfgl-package "pkg1"
+                                          :name 'pkg1
+                                          :owners '(layer16 layer15)
+                                          :step 'pre))
                       configuration-layer--packages))))))
 
 (ert-deftest test-get-packages--last-owner-cannot-overwrite-step-pre-to-nil ()
@@ -591,7 +601,10 @@
       (spacemacs-buffer/warning (msg &rest args) ((:output nil :occur 1))))
      (let (configuration-layer--packages)
        (configuration-layer/get-packages layers)
-       (should (equal (list (cfgl-package "pkg1" :name 'pkg1 :owner 'layer16 :step 'pre))
+       (should (equal (list (cfgl-package "pkg1"
+                                          :name 'pkg1
+                                          :owners '(layer16 layer15)
+                                          :step 'pre))
                       configuration-layer--packages))))))
 
 (ert-deftest test-get-packages--last-owner-can-overwrite-exclude ()
@@ -609,7 +622,10 @@
       (spacemacs-buffer/warning (msg &rest args) ((:output nil :occur 1))))
      (let (configuration-layer--packages)
        (configuration-layer/get-packages layers)
-       (should (equal (list (cfgl-package "pkg1" :name 'pkg1 :owner 'layer18 :excluded t))
+       (should (equal (list (cfgl-package "pkg1"
+                                          :name 'pkg1
+                                          :owners '(layer18 layer17)
+                                          :excluded t))
                       configuration-layer--packages))))))
 
 (ert-deftest test-get-packages--owner-layer-can-define-toggle ()
@@ -625,7 +641,7 @@
        (configuration-layer/get-packages layers)
        (should (equal (list (cfgl-package "pkg1"
                                           :name 'pkg1
-                                          :owner 'layer19
+                                          :owners '(layer19)
                                           :toggle '(foo-toggle)))
                       configuration-layer--packages))))))
 
@@ -646,7 +662,7 @@
        (configuration-layer/get-packages layers)
        (should (equal (list (cfgl-package "pkg1"
                                           :name 'pkg1
-                                          :owner 'layer20
+                                          :owners '(layer20)
                                           :post-layers '(layer21)
                                           :toggle t))
                       configuration-layer--packages))))))
@@ -668,7 +684,7 @@
        (configuration-layer/get-packages layers)
        (should (equal (list (cfgl-package "pkg1"
                                           :name 'pkg1
-                                          :owner 'layer23
+                                          :owners '(layer23 layer22)
                                           :toggle '(bar-toggle)))
                       configuration-layer--packages))))))
 
@@ -688,9 +704,9 @@
      (let (configuration-layer--packages)
        (configuration-layer/get-packages layers)
        (should (equal (list (cfgl-package "pkg1"
-                                        :name 'pkg1
-                                        :owner 'layer23
-                                        :toggle '(bar-toggle)))
+                                          :name 'pkg1
+                                          :owners '(layer23 layer22)
+                                          :toggle '(bar-toggle)))
                       configuration-layer--packages))))))
 
 ;; ---------------------------------------------------------------------------
@@ -724,15 +740,15 @@
     (mocker-let
      ((file-exists-p (f) ((:output t)))
       (load (f) ((:output nil))))
-     (should (equal (list (cfgl-package "pkg1" :name 'pkg1 :owner 'layerall1)
-                          (cfgl-package "pkg6" :name 'pkg6 :owner 'layerall2)
-                          (cfgl-package "pkg2" :name 'pkg2 :owner 'layerall2)
-                          (cfgl-package "pkg3" :name 'pkg3 :owner 'layerall3)
-                          (cfgl-package "pkg8" :name 'pkg8 :owner 'layerall4)
-                          (cfgl-package "pkg7" :name 'pkg7 :owner 'layerall4)
-                          (cfgl-package "pkg4" :name 'pkg4 :owner 'layerall4)
-                          (cfgl-package "pkg9" :name 'pkg9 :owner 'layerall5)
-                          (cfgl-package "pkg5" :name 'pkg5 :owner 'layerall5))
+     (should (equal (list (cfgl-package "pkg1" :name 'pkg1 :owners '(layerall1))
+                          (cfgl-package "pkg6" :name 'pkg6 :owners '(layerall2))
+                          (cfgl-package "pkg2" :name 'pkg2 :owners '(layerall2))
+                          (cfgl-package "pkg3" :name 'pkg3 :owners '(layerall3))
+                          (cfgl-package "pkg8" :name 'pkg8 :owners '(layerall4))
+                          (cfgl-package "pkg7" :name 'pkg7 :owners '(layerall4))
+                          (cfgl-package "pkg4" :name 'pkg4 :owners '(layerall4))
+                          (cfgl-package "pkg9" :name 'pkg9 :owners '(layerall5))
+                          (cfgl-package "pkg5" :name 'pkg5 :owners '(layerall5)))
                     (configuration-layer/get-all-packages))))))
 
 ;; ---------------------------------------------------------------------------
@@ -740,7 +756,7 @@
 ;; ---------------------------------------------------------------------------
 
 (ert-deftest test-configure-package--init-is-evaluated ()
-  (let ((pkg (cfgl-package "pkg" :name 'pkg :owner 'layer1))
+  (let ((pkg (cfgl-package "pkg" :name 'pkg :owners '(layer1)))
         (configuration-layer--layers `(,(cfgl-layer "layer1" :name 'layer1)))
         (mocker-mock-default-record-cls 'mocker-stub-record))
     (defun layer1/init-pkg nil)
@@ -750,7 +766,7 @@
      (configuration-layer//configure-package pkg))))
 
 (ert-deftest test-configure-package--pre-init-is-evaluated ()
-  (let ((pkg (cfgl-package "pkg" :name 'pkg :owner 'layer1 :pre-layers '(layer2)))
+  (let ((pkg (cfgl-package "pkg" :name 'pkg :owners '(layer1) :pre-layers '(layer2)))
         (configuration-layer--layers
          `(,(cfgl-layer "layer1" :name 'layer1)
            ,(cfgl-layer "layer2" :name 'layer2)))
@@ -763,7 +779,7 @@
      (configuration-layer//configure-package pkg))))
 
 (ert-deftest test-configure-package--post-init-is-evaluated ()
-  (let ((pkg (cfgl-package "pkg" :name 'pkg :owner 'layer1 :post-layers '(layer2)))
+  (let ((pkg (cfgl-package "pkg" :name 'pkg :owners '(layer1) :post-layers '(layer2)))
         (configuration-layer--layers
          `(,(cfgl-layer "layer1" :name 'layer1)
            ,(cfgl-layer "layer2" :name 'layer2)))
@@ -776,7 +792,7 @@
      (configuration-layer//configure-package pkg))))
 
 (ert-deftest test-configure-package--pre-init-is-evaluated-before-init ()
-  (let ((pkg (cfgl-package "pkg" :name 'pkg :owner 'layer1 :pre-layers '(layer2)))
+  (let ((pkg (cfgl-package "pkg" :name 'pkg :owners '(layer1) :pre-layers '(layer2)))
         (configuration-layer--layers
          `(,(cfgl-layer "layer1" :name 'layer1)
            ,(cfgl-layer "layer2" :name 'layer2)))
@@ -790,7 +806,7 @@
      (should (equal '(init pre-init) witness)))))
 
 (ert-deftest test-configure-package--post-init-is-evaluated-after-init ()
-  (let ((pkg (cfgl-package "pkg" :name 'pkg :owner 'layer1 :post-layers '(layer2)))
+  (let ((pkg (cfgl-package "pkg" :name 'pkg :owners '(layer1) :post-layers '(layer2)))
         (configuration-layer--layers
          `(,(cfgl-layer "layer1" :name 'layer1)
            ,(cfgl-layer "layer2" :name 'layer2)))
@@ -804,7 +820,7 @@
      (should (equal '(post-init init) witness)))))
 
 (ert-deftest test-configure-package--disabled-for-does-not-call-pre-post-init ()
-  (let ((pkg (cfgl-package "pkg" :name 'pkg :owner 'layer1
+  (let ((pkg (cfgl-package "pkg" :name 'pkg :owners '(layer1)
                            :pre-layers '(layer2)
                            :post-layers '(layer3)))
         (configuration-layer--layers
@@ -826,7 +842,7 @@
 ;; ---------------------------------------------------------------------------
 
 (ert-deftest test-configure-packages-2--package-w/-layer-owner-is-configured()
-  (let ((pkg (cfgl-package "pkg" :name 'pkg :owner 'layer1))
+  (let ((pkg (cfgl-package "pkg" :name 'pkg :owners '(layer1)))
         (mocker-mock-default-record-cls 'mocker-stub-record))
     (mocker-let
      ((configuration-layer//configure-package (p) ((:occur 1)))
@@ -834,7 +850,7 @@
      (configuration-layer//configure-packages-2 `(,pkg)))))
 
 (ert-deftest test-configure-packages-2--site-package-is-configured()
-  (let ((pkg (cfgl-package "pkg" :name 'pkg :owner 'layer1 :location 'site))
+  (let ((pkg (cfgl-package "pkg" :name 'pkg :owners '(layer1) :location 'site))
         (mocker-mock-default-record-cls 'mocker-stub-record))
     (mocker-let
      ((configuration-layer//configure-package (p) ((:occur 1)))
@@ -842,7 +858,7 @@
      (configuration-layer//configure-packages-2 `(,pkg)))))
 
 (ert-deftest test-configure-packages-2--toggle-t-is-configured ()
-  (let ((pkg (cfgl-package "pkg" :name 'pkg :owner 'layer1 :toggle t))
+  (let ((pkg (cfgl-package "pkg" :name 'pkg :owners '(layer1) :toggle t))
         (mocker-mock-default-record-cls 'mocker-stub-record))
     (mocker-let
      ((configuration-layer//configure-package (p) ((:occur 1)))
@@ -850,7 +866,7 @@
      (configuration-layer//configure-packages-2 `(,pkg)))))
 
 (ert-deftest test-configure-packages-2--toggle-nil-is-not-configured ()
-  (let ((pkg (cfgl-package "pkg" :name 'pkg :owner 'layer1 :toggle nil))
+  (let ((pkg (cfgl-package "pkg" :name 'pkg :owners '(layer1) :toggle nil))
         (mocker-mock-default-record-cls 'mocker-stub-record))
     (mocker-let
      ((configuration-layer//configure-package (p) nil)
@@ -859,7 +875,7 @@
      (configuration-layer//configure-packages-2 `(,pkg)))))
 
 (ert-deftest test-configure-packages-2--protected-package-is-configured()
-  (let ((pkg (cfgl-package "pkg" :name 'pkg :owner 'layer1 :protected t))
+  (let ((pkg (cfgl-package "pkg" :name 'pkg :owners '(layer1) :protected t))
         (mocker-mock-default-record-cls 'mocker-stub-record))
     (mocker-let
      ((configuration-layer//configure-package (p) ((:occur 1)))
@@ -867,7 +883,7 @@
      (configuration-layer//configure-packages-2 `(,pkg)))))
 
 (ert-deftest test-configure-packages-2--protected-excluded-package-is-configured()
-  (let ((pkg (cfgl-package "pkg" :name 'pkg :owner 'layer1 :excluded t :protected t))
+  (let ((pkg (cfgl-package "pkg" :name 'pkg :owners '(layer1) :excluded t :protected t))
         (mocker-mock-default-record-cls 'mocker-stub-record))
     (mocker-let
      ((configuration-layer//configure-package (p) ((:occur 1)))
@@ -875,7 +891,7 @@
      (configuration-layer//configure-packages-2 `(,pkg)))))
 
 (ert-deftest test-configure-packages-2--excluded-package-is-not-configured()
-  (let ((pkg (cfgl-package "pkg" :name 'pkg :owner 'layer1 :excluded t))
+  (let ((pkg (cfgl-package "pkg" :name 'pkg :owners '(layer1) :excluded t))
         (mocker-mock-default-record-cls 'mocker-stub-record))
     (mocker-let
      ((configuration-layer//configure-package (p) nil)
@@ -884,7 +900,7 @@
      (configuration-layer//configure-packages-2 `(,pkg)))))
 
 (ert-deftest test-configure-packages-2--package-w/o-owner-is-not-configured()
-  (let ((pkg (cfgl-package "pkg" :name 'pkg :owner nil))
+  (let ((pkg (cfgl-package "pkg" :name 'pkg :owners nil))
         (mocker-mock-default-record-cls 'mocker-stub-record))
     (mocker-let
      ((configuration-layer//configure-package (p) nil)
@@ -894,7 +910,7 @@
 
 (ert-deftest
     test-configure-packages-2--package-owned-by-dotfile-is-not-configured()
-  (let ((pkg (cfgl-package "pkg" :name 'pkg :owner 'dotfile))
+  (let ((pkg (cfgl-package "pkg" :name 'pkg :owners '(dotfile)))
         (mocker-mock-default-record-cls 'mocker-stub-record))
     (mocker-let
      ((configuration-layer//configure-package (p) nil)
@@ -903,7 +919,7 @@
      (configuration-layer//configure-packages-2 `(,pkg)))))
 
 (ert-deftest test-configure-packages-2--lazy-install-package-is-not-configured()
-  (let ((pkg (cfgl-package "pkg" :name 'pkg :owner 'layer :lazy-install t))
+  (let ((pkg (cfgl-package "pkg" :name 'pkg :owners '(layer) :lazy-install t))
         (mocker-mock-default-record-cls 'mocker-stub-record))
     (mocker-let
      ((configuration-layer//configure-package (p) nil)
@@ -913,7 +929,7 @@
 
 (ert-deftest
     test-configure-packages-2--local-package-w/-layer-owner-update-load-path()
-  (let ((pkg (cfgl-package "pkg" :name 'pkg :owner 'layer1 :location 'local))
+  (let ((pkg (cfgl-package "pkg" :name 'pkg :owners '(layer1) :location 'local))
         (configuration-layer--layers `(,(cfgl-layer "layer1"
                                                     :name 'layer1
                                                     :dir "/a/path/")))
@@ -928,7 +944,7 @@
 
 (ert-deftest
     test-configure-packages-2--local-package-w/-dotfile-owner-update-load-path()
-  (let ((pkg (cfgl-package "pkg" :name 'pkg :owner 'dotfile :location 'local))
+  (let ((pkg (cfgl-package "pkg" :name 'pkg :owners '(dotfile) :location 'local))
         (expected-load-path load-path)
         (mocker-mock-default-record-cls 'mocker-stub-record))
     (mocker-let
@@ -941,7 +957,7 @@
 
 (ert-deftest
     test-configure-packages-2--local-package-w/o-owner-doesnt-update-load-path()
-  (let ((pkg (cfgl-package "pkg" :name 'pkg :owner nil :location 'local))
+  (let ((pkg (cfgl-package "pkg" :name 'pkg :owners nil :location 'local))
         (old-load-path load-path)
         (mocker-mock-default-record-cls 'mocker-stub-record))
     (mocker-let
@@ -954,7 +970,7 @@
     test-configure-packages-2--local-package-w/-string-location-update-load-path()
   (let ((pkg (cfgl-package "pkg"
                            :name 'pkg
-                           :owner 'dotfile
+                           :owners '(dotfile)
                            :location spacemacs-docs-directory))
         (expected-load-path load-path)
         (mocker-mock-default-record-cls 'mocker-stub-record))
@@ -968,7 +984,7 @@
     test-configure-packages-2--local-package-w/-bad-string-location-gives-warning()
   (let ((pkg (cfgl-package "pkg"
                            :name 'pkg
-                           :owner 'dotfile
+                           :owners '(dotfile)
                            :location "/this/directory/does/not/exist/"))
         (mocker-mock-default-record-cls 'mocker-stub-record))
     (mocker-let
@@ -1139,9 +1155,9 @@
          (layer1-packages '(pkg1 pkg2 pkg3))
          (mocker-mock-default-record-cls 'mocker-stub-record)
          (configuration-layer--packages
-          (list (cfgl-package "pkg3" :name 'pkg3 :owner 'layer1)
-                (cfgl-package "pkg2" :name 'pkg2 :owner 'layer1)
-                (cfgl-package "pkg1" :name 'pkg1 :owner 'layer1))))
+          (list (cfgl-package "pkg3" :name 'pkg3 :owners '(layer1))
+                (cfgl-package "pkg2" :name 'pkg2 :owners '(layer1))
+                (cfgl-package "pkg1" :name 'pkg1 :owners '(layer1)))))
     (should (configuration-layer/package-usedp (nth (random 3)
                                                     layer1-packages)))))
 
@@ -1315,8 +1331,8 @@
   (let ((configuration-layer--layers
          (list (cfgl-layer "layer" :name 'layer :packages '(pkg1 pkg2))))
         (configuration-layer--packages
-         (list (cfgl-package "pkg1" :name 'pkg1 :owner 'layer)
-               (cfgl-package "pkg2" :name 'pkg2 :owner 'layer)))
+         (list (cfgl-package "pkg1" :name 'pkg1 :owners '(layer))
+               (cfgl-package "pkg2" :name 'pkg2 :owners '(layer))))
         (auto-mode-alist '(("\\.pkg1\\'" . pkg1)
                            ("\\.pkg2\\'" . pkg2))))
     (should (equal '((pkg2 . "\\(\\.pkg2\\'\\)")
@@ -1327,7 +1343,7 @@
   (let ((configuration-layer--layers
          (list (cfgl-layer "layer" :name 'layer :packages '(pkg1))))
         (configuration-layer--packages
-         (list (cfgl-package "pkg1" :name 'pkg1 :owner 'other)))
+         (list (cfgl-package "pkg1" :name 'pkg1 :owners '(other))))
         (auto-mode-alist '(("\\.pkg1\\'" . pkg1))))
     (should (null (configuration-layer//lazy-install-extensions-for-layer 'layer)))))