diff --git a/exwm-core.el b/exwm-core.el
index 39964d2..9f869fe 100644
--- a/exwm-core.el
+++ b/exwm-core.el
@@ -119,6 +119,15 @@
 ;; _MOTIF_WM_HINTS
 (defvar-local exwm--mwm-hints-decorations t)
 
+(declare-function exwm-floating-hide "exwm-floating.el")
+(declare-function exwm-floating-toggle-floating "exwm-floating.el")
+(declare-function exwm-input-release-keyboard "exwm-input.el")
+(declare-function exwm-input-send-next-key "exwm-input.el" (times))
+(declare-function exwm-layout-set-fullscreen "exwm-layout.el" (&optional id))
+(declare-function exwm-layout-toggle-mode-line "exwm-layout.el")
+(declare-function exwm-workspace-move-window "exwm-workspace.el"
+                  (index &optional id))
+
 (defvar exwm-mode-map
   (let ((map (make-sparse-keymap)))
     (define-key map "\C-c\C-f" #'exwm-layout-set-fullscreen)
diff --git a/exwm-floating.el b/exwm-floating.el
index 9d4d948..b58e71a 100644
--- a/exwm-floating.el
+++ b/exwm-floating.el
@@ -67,13 +67,11 @@
                                      xcb:Atom:_NET_WM_ACTION_CLOSE)))))
 
 (defvar exwm-workspace--current)
-(defvar exwm-workspace--list)
-(defvar exwm-workspace-current-index)
-(defvar exwm-workspace--switch-history-outdated)
 
 (declare-function exwm-layout--refresh "exwm-layout.el" ())
 (declare-function exwm-layout--show "exwm-layout.el" (id &optional window))
 (declare-function exwm-layout--iconic-state-p "exwm-layout.el" (&optional id))
+(declare-function exwm-workspace--minibuffer-own-frame-p "exwm-workspace.el")
 
 (defun exwm-floating--set-floating (id)
   "Make window ID floating."
diff --git a/exwm-input.el b/exwm-input.el
index 6f18fbf..67e9a74 100644
--- a/exwm-input.el
+++ b/exwm-input.el
@@ -102,6 +102,9 @@ It's updated in several occasions, and only used by `exwm-input--set-focus'.")
 
 (declare-function exwm-layout--iconic-state-p "exwm-layout.el" (&optional id))
 (declare-function exwm-layout--set-state "exwm-layout.el" (id state))
+(declare-function exwm-workspace--minibuffer-own-frame-p "exwm-workspace.el")
+(declare-function exwm-workspace-switch "exwm-workspace.el"
+                  (index &optional force))
 
 (defun exwm-input--update-focus ()
   "Update input focus."
diff --git a/exwm-layout.el b/exwm-layout.el
index 85e186f..92ca677 100644
--- a/exwm-layout.el
+++ b/exwm-layout.el
@@ -155,7 +155,15 @@
 (defvar exwm-workspace--current)
 (defvar exwm-workspace--list)
 
+(declare-function exwm-input-grab-keyboard "exwm-input.el")
+(declare-function exwm-input-release-keyboard "exwm-input.el")
+(declare-function exwm-workspace--current-height "exwm-workspace.el")
+(declare-function exwm-workspace--current-width  "exwm-workspace.el")
+(declare-function exwm-workspace--get-geometry "exwm-workspace.el" (frame))
+(declare-function exwm-workspace--minibuffer-own-frame-p "exwm-workspace.el")
 (declare-function exwm-workspace--set-fullscreen "exwm-workspace.el" (frame))
+(declare-function exwm-workspace-move-window "exwm-workspace.el"
+                  (index &optional id))
 
 ;;;###autoload
 (defun exwm-layout-set-fullscreen (&optional id)
diff --git a/exwm-manage.el b/exwm-manage.el
index 18a6795..01d00b1 100644
--- a/exwm-manage.el
+++ b/exwm-manage.el
@@ -89,7 +89,12 @@ corresponding buffer.")
 (declare-function exwm--update-struts "exwm.el" (id))
 (declare-function exwm-floating--set-floating "exwm-floating.el" (id))
 (declare-function exwm-floating--unset-floating "exwm-floating.el" (id))
+(declare-function exwm-input-grab-keyboard "exwm-input.el")
+(declare-function exwm-workspace--current-height "exwm-workspace.el")
+(declare-function exwm-workspace--current-width  "exwm-workspace.el")
 (declare-function exwm-workspace--set-desktop "exwm-workspace.el" (id))
+(declare-function exwm-workspace-move-window "exwm-workspace.el"
+                  (index &optional id))
 
 (defun exwm-manage--manage-window (id)
   "Manage window ID."
diff --git a/exwm-systemtray.el b/exwm-systemtray.el
index db0e045..56e5fb8 100644
--- a/exwm-systemtray.el
+++ b/exwm-systemtray.el
@@ -65,6 +65,11 @@ You shall use the default value if using auto-hide minibuffer.")
   "The selection owner window.")
 (defvar exwm-systemtray--embedder nil "The embedder window.")
 
+(defvar exwm-workspace--current)
+(declare-function exwm-workspace--current-height "exwm-workspace.el")
+(declare-function exwm-workspace--current-width  "exwm-workspace.el")
+(declare-function exwm-workspace--minibuffer-own-frame-p "exwm-workspace.el")
+
 (defun exwm-systemtray--embed (icon)
   "Embed an icon."
   (exwm--log "(System Tray) Try to embed #x%x" icon)
@@ -266,8 +271,6 @@ You shall use the default value if using auto-hide minibuffer.")
               (t
                (exwm--log "(System Tray) Unknown opcode message: %s" obj)))))))
 
-(defvar exwm-workspace--current)
-
 (defun exwm-systemtray--on-workspace-switch ()
   "Reparent/Refresh the system tray in `exwm-workspace-switch-hook'."
   (unless (exwm-workspace--minibuffer-own-frame-p)