diff --git a/helm-org-ql.el b/helm-org-ql.el
index e75cf7b..a47ecce 100644
--- a/helm-org-ql.el
+++ b/helm-org-ql.el
@@ -2,6 +2,8 @@
 
 ;; Author: Adam Porter <adam@alphapapa.net>
 ;; URL: https://github.com/alphapapa/org-ql
+;; Version: 0.6-pre
+;; Package-Requires: ((emacs "26.1") (dash "2.17.0") (s "1.12.0") (helm-org "1.0") (org-ql "0.6-pre"))
 
 ;;; Commentary:
 
@@ -28,84 +30,72 @@
 
 ;;; Code:
 
-(eval-and-compile
+;;;; Requirements
 
-  (require 'org)
-  (require 'org-ql)
-  (require 'org-ql-search)
+(require 'cl-lib)
+(require 'org)
 
-;;;; Compatibility
+(require 'dash)
+(require 's)
 
-  ;; Declare Helm functions since Helm may not be installed.
-  (declare-function helm "ext:helm")
-  (declare-function helm-run-after-exit "ext:helm")
-  (declare-function helm-window "ext:helm-lib")
-  (declare-function helm-buffer-get "ext:helm-lib")
-  (declare-function helm-make-source "ext:helm-source")
-  (declare-function helm-org-goto-marker "ext:helm-org")
+(require 'helm)
+(require 'helm-org)
 
-  ;; Silence byte-compiler about variables.
-  (defvar helm-map)
-  (defvar helm-pattern)
-  (defvar helm-input-idle-delay)
-
-  (when (require 'helm nil 'noerror)
-
-    ;; Requirements.
-    (require 'helm-org)
+(require 'org-ql)
+(require 'org-ql-search)
 
 ;;;; Variables
 
-    (defvar helm-org-ql-map
-      (let ((map (make-sparse-keymap))
-            (mappings '("C-x C-s" helm-org-ql-save)))
-        (cl-loop for (key fn) on mappings by #'cddr
-                 do (define-key map (kbd key) fn))
-        (make-composed-keymap map helm-map))
-      "Keymap for `helm-org-ql' sessions.
+(defvar helm-org-ql-map
+  (let ((map (make-sparse-keymap))
+        (mappings '("C-x C-s" helm-org-ql-save)))
+    (cl-loop for (key fn) on mappings by #'cddr
+             do (define-key map (kbd key) fn))
+    (make-composed-keymap map helm-map))
+  "Keymap for `helm-org-ql' sessions.
 Based on `helm-map'.")
 
-    (defvar helm-source-org-ql-views
-      (helm-make-source "Org QL Views" 'helm-source-sync
-        :candidates (lambda ()
-                      (->> org-ql-views
-                           (-map #'car)
-                           (-sort #'string<)))
-        :action (list (cons "Show view" #'org-ql-view)))
-      "Helm source for `org-ql-views'.")
+(defvar helm-source-org-ql-views
+  (helm-make-source "Org QL Views" 'helm-source-sync
+    :candidates (lambda ()
+                  (->> org-ql-views
+                       (-map #'car)
+                       (-sort #'string<)))
+    :action (list (cons "Show view" #'org-ql-view)))
+  "Helm source for `org-ql-views'.")
 
-    (with-no-warnings
-      ;; Silence compiler warning: "‘make-variable-buffer-local’ not called at toplevel"
-      (defvar-local helm-org-ql-buffers-files nil
-        "Used for `helm-org-ql-save'."))
+(with-no-warnings
+  ;; Silence compiler warning: "‘make-variable-buffer-local’ not called at toplevel"
+  (defvar-local helm-org-ql-buffers-files nil
+    "Used for `helm-org-ql-save'."))
 
 ;;;; Customization
 
-    (defgroup helm-org-ql nil
-      "Options for `helm-org-ql'."
-      :group 'org-ql)
+(defgroup helm-org-ql nil
+  "Options for `helm-org-ql'."
+  :group 'org-ql)
 
-    (defcustom helm-org-ql-reverse-paths t
-      "Whether to reverse Org outline paths in `helm-org-ql' results."
-      :type 'boolean)
+(defcustom helm-org-ql-reverse-paths t
+  "Whether to reverse Org outline paths in `helm-org-ql' results."
+  :type 'boolean)
 
-    (defcustom helm-org-ql-input-idle-delay 0.25
-      "Seconds to wait after typing stops before running query."
-      :type 'number)
+(defcustom helm-org-ql-input-idle-delay 0.25
+  "Seconds to wait after typing stops before running query."
+  :type 'number)
 
-    (defcustom helm-org-ql-actions
-      (list (cons "Show heading in source buffer" 'helm-org-ql-show-marker)
-            (cons "Show heading in indirect buffer" 'helm-org-ql-show-marker-indirect))
-      "Alist of actions for `helm-org-ql' commands."
-      :type '(alist :key-type (string :tag "Description")
-                    :value-type (function :tag "Command")))
+(defcustom helm-org-ql-actions
+  (list (cons "Show heading in source buffer" 'helm-org-ql-show-marker)
+        (cons "Show heading in indirect buffer" 'helm-org-ql-show-marker-indirect))
+  "Alist of actions for `helm-org-ql' commands."
+  :type '(alist :key-type (string :tag "Description")
+                :value-type (function :tag "Command")))
 
 ;;;; Commands
 
 ;;;###autoload
-    (cl-defun helm-org-ql (buffers-files
-                           &key (boolean 'and) (name "helm-org-ql"))
-      "Display results in BUFFERS-FILES for an `org-ql' non-sexp query using Helm.
+(cl-defun helm-org-ql (buffers-files
+                       &key (boolean 'and) (name "helm-org-ql"))
+  "Display results in BUFFERS-FILES for an `org-ql' non-sexp query using Helm.
 Interactively, search the current buffer.  Note that this command
 only accepts non-sexp, \"plain\" queries.
 
@@ -132,99 +122,99 @@ However, quoted strings remain quoted, so this input:
 Is transformed into this query:
 
     (and \"something else\" (tags \"funny\"))"
-      (interactive (list (current-buffer)))
-      (let ((boolean (if current-prefix-arg 'or boolean))
-            (helm-input-idle-delay helm-org-ql-input-idle-delay))
-        (helm :prompt (format "Query (boolean %s): " (-> boolean symbol-name upcase))
-              :sources (helm-org-ql-source buffers-files :name name))))
+  (interactive (list (current-buffer)))
+  (let ((boolean (if current-prefix-arg 'or boolean))
+        (helm-input-idle-delay helm-org-ql-input-idle-delay))
+    (helm :prompt (format "Query (boolean %s): " (-> boolean symbol-name upcase))
+          :sources (helm-org-ql-source buffers-files :name name))))
 
 ;;;###autoload
-    (defun helm-org-ql-agenda-files ()
-      "Search agenda files with `helm-org-ql', which see."
-      (interactive)
-      (helm-org-ql (org-agenda-files) :name "Org Agenda Files"))
+(defun helm-org-ql-agenda-files ()
+  "Search agenda files with `helm-org-ql', which see."
+  (interactive)
+  (helm-org-ql (org-agenda-files) :name "Org Agenda Files"))
 
 ;;;###autoload
-    (defun helm-org-ql-org-directory ()
-      "Search Org files in `org-directory' with `helm-org-ql'."
-      (interactive)
-      (helm-org-ql (org-ql-search-directories-files)
-                   :name "Org Directory Files"))
+(defun helm-org-ql-org-directory ()
+  "Search Org files in `org-directory' with `helm-org-ql'."
+  (interactive)
+  (helm-org-ql (org-ql-search-directories-files)
+               :name "Org Directory Files"))
 
-    (defun helm-org-ql-show-marker (marker)
-      "Show heading at MARKER."
-      (interactive)
-      ;; This function is necessary because `helm-org-goto-marker' calls
-      ;; `re-search-backward' to go backward to the start of a heading,
-      ;; which, when the marker is already at the desired heading, causes
-      ;; it to go to the previous heading.  I don't know why it does that.
-      (switch-to-buffer (marker-buffer marker))
-      (goto-char marker)
-      (org-show-entry))
+(defun helm-org-ql-show-marker (marker)
+  "Show heading at MARKER."
+  (interactive)
+  ;; This function is necessary because `helm-org-goto-marker' calls
+  ;; `re-search-backward' to go backward to the start of a heading,
+  ;; which, when the marker is already at the desired heading, causes
+  ;; it to go to the previous heading.  I don't know why it does that.
+  (switch-to-buffer (marker-buffer marker))
+  (goto-char marker)
+  (org-show-entry))
 
-    (defun helm-org-ql-show-marker-indirect (marker)
-      "Show heading at MARKER with `org-tree-to-indirect-buffer'."
-      (interactive)
-      (helm-org-ql-show-marker marker)
-      (org-tree-to-indirect-buffer))
+(defun helm-org-ql-show-marker-indirect (marker)
+  "Show heading at MARKER with `org-tree-to-indirect-buffer'."
+  (interactive)
+  (helm-org-ql-show-marker marker)
+  (org-tree-to-indirect-buffer))
 
-    (defun helm-org-ql-save ()
-      "Show `helm-org-ql' search in an `org-ql-search' buffer."
-      (interactive)
-      (let ((buffers-files (with-current-buffer (helm-buffer-get)
-                             helm-org-ql-buffers-files))
-            (query (org-ql--query-string-to-sexp helm-pattern)))
-        (helm-run-after-exit #'org-ql-search buffers-files query)))
+(defun helm-org-ql-save ()
+  "Show `helm-org-ql' search in an `org-ql-search' buffer."
+  (interactive)
+  (let ((buffers-files (with-current-buffer (helm-buffer-get)
+                         helm-org-ql-buffers-files))
+        (query (org-ql--query-string-to-sexp helm-pattern)))
+    (helm-run-after-exit #'org-ql-search buffers-files query)))
 
 ;;;###autoload
-    (defun helm-org-ql-views ()
-      "Show an `org-ql' view selected with Helm."
-      (interactive)
-      (helm :sources helm-source-org-ql-views))
+(defun helm-org-ql-views ()
+  "Show an `org-ql' view selected with Helm."
+  (interactive)
+  (helm :sources helm-source-org-ql-views))
 
 ;;;; Functions
 
-    (cl-defun helm-org-ql-source (buffers-files &key (name "helm-org-ql"))
-      "Return Helm source named NAME that searches BUFFERS-FILES with `helm-org-ql'."
-      ;; Expansion of `helm-build-sync-source' macro.
-      (helm-make-source name 'helm-source-sync
-        :candidates (lambda ()
-                      (let* ((query (org-ql--query-string-to-sexp helm-pattern))
-                             (window-width (window-width (helm-window))))
-                        (when query
-                          (with-current-buffer (helm-buffer-get)
-                            (setq helm-org-ql-buffers-files buffers-files))
-                          (ignore-errors
-                            ;; Ignore errors that might be caused by partially typed queries.
-                            (org-ql-select buffers-files query
-                              :action `(helm-org-ql--heading ,window-width))))))
-        :match #'identity
-        :fuzzy-match nil
-        :multimatch nil
-        :nohighlight t
-        :volatile t
-        :keymap helm-org-ql-map
-        :action helm-org-ql-actions))
+(cl-defun helm-org-ql-source (buffers-files &key (name "helm-org-ql"))
+  "Return Helm source named NAME that searches BUFFERS-FILES with `helm-org-ql'."
+  ;; Expansion of `helm-build-sync-source' macro.
+  (helm-make-source name 'helm-source-sync
+    :candidates (lambda ()
+                  (let* ((query (org-ql--query-string-to-sexp helm-pattern))
+                         (window-width (window-width (helm-window))))
+                    (when query
+                      (with-current-buffer (helm-buffer-get)
+                        (setq helm-org-ql-buffers-files buffers-files))
+                      (ignore-errors
+                        ;; Ignore errors that might be caused by partially typed queries.
+                        (org-ql-select buffers-files query
+                          :action `(helm-org-ql--heading ,window-width))))))
+    :match #'identity
+    :fuzzy-match nil
+    :multimatch nil
+    :nohighlight t
+    :volatile t
+    :keymap helm-org-ql-map
+    :action helm-org-ql-actions))
 
-    (defun helm-org-ql--heading (window-width)
-      "Return string for Helm for heading at point.
+(defun helm-org-ql--heading (window-width)
+  "Return string for Helm for heading at point.
 WINDOW-WIDTH should be the width of the Helm window."
-      (font-lock-ensure (point-at-bol) (point-at-eol))
-      ;; TODO: It would be better to avoid calculating the prefix and width
-      ;; at each heading, but there's no easy way to do that once in each
-      ;; buffer, unless we manually called `org-ql' in each buffer, which
-      ;; I'd prefer not to do.  Maybe I should add a feature to `org-ql' to
-      ;; call a setup function in a buffer before running queries.
-      (let* ((prefix (concat (buffer-name) ":"))
-             (width (- window-width (length prefix)))
-             (heading (org-get-heading t))
-             (path (-> (org-get-outline-path)
-                       (org-format-outline-path width nil "")
-                       (org-split-string "")))
-             (path (if helm-org-ql-reverse-paths
-                       (concat heading "\\" (s-join "\\" (nreverse path)))
-                     (concat (s-join "/" path) "/" heading))))
-        (cons (concat prefix path) (point-marker))))))
+  (font-lock-ensure (point-at-bol) (point-at-eol))
+  ;; TODO: It would be better to avoid calculating the prefix and width
+  ;; at each heading, but there's no easy way to do that once in each
+  ;; buffer, unless we manually called `org-ql' in each buffer, which
+  ;; I'd prefer not to do.  Maybe I should add a feature to `org-ql' to
+  ;; call a setup function in a buffer before running queries.
+  (let* ((prefix (concat (buffer-name) ":"))
+         (width (- window-width (length prefix)))
+         (heading (org-get-heading t))
+         (path (-> (org-get-outline-path)
+                   (org-format-outline-path width nil "")
+                   (org-split-string "")))
+         (path (if helm-org-ql-reverse-paths
+                   (concat heading "\\" (s-join "\\" (nreverse path)))
+                 (concat (s-join "/" path) "/" heading))))
+    (cons (concat prefix path) (point-marker)))))
 
 ;;;; Footer