diff --git a/oni-bats/Cask b/oni-bats/Cask
deleted file mode 100644
index 1a6e405..0000000
--- a/oni-bats/Cask
+++ /dev/null
@@ -1,8 +0,0 @@
-(source gnu)
-(source melpa)
-
-(package-file "./oni-bats.el")
-
-(files
- "*.el"
- ("snippets" "./snippets/*"))
diff --git a/oni-bats/Eldev b/oni-bats/Eldev
new file mode 100644
index 0000000..1ba3134
--- /dev/null
+++ b/oni-bats/Eldev
@@ -0,0 +1,13 @@
+; -*- mode: emacs-lisp; lexical-binding: t -*-
+
+;; Uncomment some calls below as needed for your project.
+(eldev-use-package-archive 'gnu-elpa)
+;(eldev-use-package-archive 'nongnu-elpa)
+(eldev-use-package-archive 'melpa)
+(eldev-use-package-archive `("oni" . ,(expand-file-name "../bin")))
+
+(eldev-use-plugin 'autoloads)
+
+(setf eldev-files-to-package
+      `(:or ,eldev-files-to-package
+            '("*.el" "./snippets/**/*")))
diff --git a/oni-conf/Cask b/oni-conf/Cask
deleted file mode 100644
index 064d0bb..0000000
--- a/oni-conf/Cask
+++ /dev/null
@@ -1,8 +0,0 @@
-(source gnu)
-(source melpa)
-
-(package-file "./oni-conf.el")
-
-(files
- "*.el"
- ("snippets" "./snippets/*"))
diff --git a/oni-conf/Eldev b/oni-conf/Eldev
new file mode 100644
index 0000000..1ba3134
--- /dev/null
+++ b/oni-conf/Eldev
@@ -0,0 +1,13 @@
+; -*- mode: emacs-lisp; lexical-binding: t -*-
+
+;; Uncomment some calls below as needed for your project.
+(eldev-use-package-archive 'gnu-elpa)
+;(eldev-use-package-archive 'nongnu-elpa)
+(eldev-use-package-archive 'melpa)
+(eldev-use-package-archive `("oni" . ,(expand-file-name "../bin")))
+
+(eldev-use-plugin 'autoloads)
+
+(setf eldev-files-to-package
+      `(:or ,eldev-files-to-package
+            '("*.el" "./snippets/**/*")))
diff --git a/oni-csharp/Cask b/oni-csharp/Cask
deleted file mode 100644
index e42c835..0000000
--- a/oni-csharp/Cask
+++ /dev/null
@@ -1,8 +0,0 @@
-(source gnu)
-(source melpa)
-
-(package-file "./oni-csharp.el")
-
-(files
- "*.el"
- ("snippets" "./snippets/*"))
diff --git a/oni-csharp/Eldev b/oni-csharp/Eldev
new file mode 100644
index 0000000..1ba3134
--- /dev/null
+++ b/oni-csharp/Eldev
@@ -0,0 +1,13 @@
+; -*- mode: emacs-lisp; lexical-binding: t -*-
+
+;; Uncomment some calls below as needed for your project.
+(eldev-use-package-archive 'gnu-elpa)
+;(eldev-use-package-archive 'nongnu-elpa)
+(eldev-use-package-archive 'melpa)
+(eldev-use-package-archive `("oni" . ,(expand-file-name "../bin")))
+
+(eldev-use-plugin 'autoloads)
+
+(setf eldev-files-to-package
+      `(:or ,eldev-files-to-package
+            '("*.el" "./snippets/**/*")))
diff --git a/oni-css/Cask b/oni-css/Cask
deleted file mode 100644
index 40766c6..0000000
--- a/oni-css/Cask
+++ /dev/null
@@ -1,8 +0,0 @@
-(source gnu)
-(source melpa)
-
-(package-file "./oni-css.el")
-
-(files
- "*.el"
- ("snippets" "./snippets/*"))
diff --git a/oni-css/Eldev b/oni-css/Eldev
new file mode 100644
index 0000000..1ba3134
--- /dev/null
+++ b/oni-css/Eldev
@@ -0,0 +1,13 @@
+; -*- mode: emacs-lisp; lexical-binding: t -*-
+
+;; Uncomment some calls below as needed for your project.
+(eldev-use-package-archive 'gnu-elpa)
+;(eldev-use-package-archive 'nongnu-elpa)
+(eldev-use-package-archive 'melpa)
+(eldev-use-package-archive `("oni" . ,(expand-file-name "../bin")))
+
+(eldev-use-plugin 'autoloads)
+
+(setf eldev-files-to-package
+      `(:or ,eldev-files-to-package
+            '("*.el" "./snippets/**/*")))
diff --git a/oni-elisp/Cask b/oni-elisp/Cask
deleted file mode 100644
index 9f7cef0..0000000
--- a/oni-elisp/Cask
+++ /dev/null
@@ -1,8 +0,0 @@
-(source gnu)
-(source melpa)
-
-(package-file "./oni-elisp.el")
-
-(files
- "*.el"
- ("snippets" "./snippets/*"))
diff --git a/oni-elisp/Eldev b/oni-elisp/Eldev
new file mode 100644
index 0000000..1ba3134
--- /dev/null
+++ b/oni-elisp/Eldev
@@ -0,0 +1,13 @@
+; -*- mode: emacs-lisp; lexical-binding: t -*-
+
+;; Uncomment some calls below as needed for your project.
+(eldev-use-package-archive 'gnu-elpa)
+;(eldev-use-package-archive 'nongnu-elpa)
+(eldev-use-package-archive 'melpa)
+(eldev-use-package-archive `("oni" . ,(expand-file-name "../bin")))
+
+(eldev-use-plugin 'autoloads)
+
+(setf eldev-files-to-package
+      `(:or ,eldev-files-to-package
+            '("*.el" "./snippets/**/*")))
diff --git a/oni-haml/Cask b/oni-haml/Cask
deleted file mode 100644
index 9bcc49f..0000000
--- a/oni-haml/Cask
+++ /dev/null
@@ -1,8 +0,0 @@
-(source gnu)
-(source melpa)
-
-(package-file "./oni-haml.el")
-
-(files
- "*.el"
- ("snippets" "./snippets/*"))
diff --git a/oni-haml/Eldev b/oni-haml/Eldev
new file mode 100644
index 0000000..1ba3134
--- /dev/null
+++ b/oni-haml/Eldev
@@ -0,0 +1,13 @@
+; -*- mode: emacs-lisp; lexical-binding: t -*-
+
+;; Uncomment some calls below as needed for your project.
+(eldev-use-package-archive 'gnu-elpa)
+;(eldev-use-package-archive 'nongnu-elpa)
+(eldev-use-package-archive 'melpa)
+(eldev-use-package-archive `("oni" . ,(expand-file-name "../bin")))
+
+(eldev-use-plugin 'autoloads)
+
+(setf eldev-files-to-package
+      `(:or ,eldev-files-to-package
+            '("*.el" "./snippets/**/*")))
diff --git a/oni-html/Cask b/oni-html/Cask
deleted file mode 100644
index f985d16..0000000
--- a/oni-html/Cask
+++ /dev/null
@@ -1,8 +0,0 @@
-(source gnu)
-(source melpa)
-
-(package-file "./oni-html.el")
-
-(files
- "*.el"
- ("snippets" "./snippets/*"))
diff --git a/oni-html/Eldev b/oni-html/Eldev
new file mode 100644
index 0000000..1ba3134
--- /dev/null
+++ b/oni-html/Eldev
@@ -0,0 +1,13 @@
+; -*- mode: emacs-lisp; lexical-binding: t -*-
+
+;; Uncomment some calls below as needed for your project.
+(eldev-use-package-archive 'gnu-elpa)
+;(eldev-use-package-archive 'nongnu-elpa)
+(eldev-use-package-archive 'melpa)
+(eldev-use-package-archive `("oni" . ,(expand-file-name "../bin")))
+
+(eldev-use-plugin 'autoloads)
+
+(setf eldev-files-to-package
+      `(:or ,eldev-files-to-package
+            '("*.el" "./snippets/**/*")))
diff --git a/oni-nxml/Cask b/oni-nxml/Cask
deleted file mode 100644
index d66d955..0000000
--- a/oni-nxml/Cask
+++ /dev/null
@@ -1,8 +0,0 @@
-(source gnu)
-(source melpa)
-
-(package-file "./oni-nxml.el")
-
-(files
- "*.el"
- ("snippets" "./snippets/*"))
diff --git a/oni-nxml/Eldev b/oni-nxml/Eldev
new file mode 100644
index 0000000..1ba3134
--- /dev/null
+++ b/oni-nxml/Eldev
@@ -0,0 +1,13 @@
+; -*- mode: emacs-lisp; lexical-binding: t -*-
+
+;; Uncomment some calls below as needed for your project.
+(eldev-use-package-archive 'gnu-elpa)
+;(eldev-use-package-archive 'nongnu-elpa)
+(eldev-use-package-archive 'melpa)
+(eldev-use-package-archive `("oni" . ,(expand-file-name "../bin")))
+
+(eldev-use-plugin 'autoloads)
+
+(setf eldev-files-to-package
+      `(:or ,eldev-files-to-package
+            '("*.el" "./snippets/**/*")))
diff --git a/oni-org/Cask b/oni-org/Cask
deleted file mode 100644
index e92ff13..0000000
--- a/oni-org/Cask
+++ /dev/null
@@ -1,10 +0,0 @@
-(source gnu)
-(source melpa)
-
-(package-file "./oni-org.el")
-
-(files
- "*.el"
- ("snippets" "./snippets/*")
- ("icons" "./icons/*")
- ("capture-templates" "./capture-templates/*"))
diff --git a/oni-org/Eldev b/oni-org/Eldev
new file mode 100644
index 0000000..7c2d187
--- /dev/null
+++ b/oni-org/Eldev
@@ -0,0 +1,20 @@
+; -*- mode: emacs-lisp; lexical-binding: t -*-
+
+;; Uncomment some calls below as needed for your project.
+(eldev-use-package-archive 'gnu-elpa)
+;(eldev-use-package-archive 'nongnu-elpa)
+(eldev-use-package-archive 'melpa)
+(eldev-use-package-archive `("oni" . ,(expand-file-name "../bin")))
+
+(eldev-use-local-dependency
+ (car (directory-files (format "%s/share/emacs/site-lisp" (getenv "GUIX_ENVIRONMENT"))
+                       t "org-pretty-table" nil 1)))
+
+(eldev-use-plugin 'autoloads)
+
+(setf eldev-files-to-package
+      `(:or ,eldev-files-to-package
+            '("*.el"
+              "./snippets/**/*"
+              "./icons/**/*"
+              "./capture-templates/**/*")))
diff --git a/oni-php/Cask b/oni-php/Cask
deleted file mode 100644
index b52c875..0000000
--- a/oni-php/Cask
+++ /dev/null
@@ -1,8 +0,0 @@
-(source gnu)
-(source melpa)
-
-(package-file "./oni-php.el")
-
-(files
- "*.el"
- ("snippets" "./snippets/*"))
diff --git a/oni-php/Eldev b/oni-php/Eldev
new file mode 100644
index 0000000..1ba3134
--- /dev/null
+++ b/oni-php/Eldev
@@ -0,0 +1,13 @@
+; -*- mode: emacs-lisp; lexical-binding: t -*-
+
+;; Uncomment some calls below as needed for your project.
+(eldev-use-package-archive 'gnu-elpa)
+;(eldev-use-package-archive 'nongnu-elpa)
+(eldev-use-package-archive 'melpa)
+(eldev-use-package-archive `("oni" . ,(expand-file-name "../bin")))
+
+(eldev-use-plugin 'autoloads)
+
+(setf eldev-files-to-package
+      `(:or ,eldev-files-to-package
+            '("*.el" "./snippets/**/*")))
diff --git a/oni-python/Cask b/oni-python/Cask
deleted file mode 100644
index 4699a2f..0000000
--- a/oni-python/Cask
+++ /dev/null
@@ -1,8 +0,0 @@
-(source gnu)
-(source melpa)
-
-(package-file "./oni-python.el")
-
-(files
- "*.el"
- ("snippets" "./snippets/*"))
diff --git a/oni-python/Eldev b/oni-python/Eldev
new file mode 100644
index 0000000..1ba3134
--- /dev/null
+++ b/oni-python/Eldev
@@ -0,0 +1,13 @@
+; -*- mode: emacs-lisp; lexical-binding: t -*-
+
+;; Uncomment some calls below as needed for your project.
+(eldev-use-package-archive 'gnu-elpa)
+;(eldev-use-package-archive 'nongnu-elpa)
+(eldev-use-package-archive 'melpa)
+(eldev-use-package-archive `("oni" . ,(expand-file-name "../bin")))
+
+(eldev-use-plugin 'autoloads)
+
+(setf eldev-files-to-package
+      `(:or ,eldev-files-to-package
+            '("*.el" "./snippets/**/*")))
diff --git a/oni-ruby/Cask b/oni-ruby/Cask
deleted file mode 100644
index 4c18388..0000000
--- a/oni-ruby/Cask
+++ /dev/null
@@ -1,8 +0,0 @@
-(source gnu)
-(source melpa)
-
-(package-file "./oni-ruby.el")
-
-(files
- "*.el"
- ("snippets" "./snippets/*"))
diff --git a/oni-ruby/Eldev b/oni-ruby/Eldev
new file mode 100644
index 0000000..1ba3134
--- /dev/null
+++ b/oni-ruby/Eldev
@@ -0,0 +1,13 @@
+; -*- mode: emacs-lisp; lexical-binding: t -*-
+
+;; Uncomment some calls below as needed for your project.
+(eldev-use-package-archive 'gnu-elpa)
+;(eldev-use-package-archive 'nongnu-elpa)
+(eldev-use-package-archive 'melpa)
+(eldev-use-package-archive `("oni" . ,(expand-file-name "../bin")))
+
+(eldev-use-plugin 'autoloads)
+
+(setf eldev-files-to-package
+      `(:or ,eldev-files-to-package
+            '("*.el" "./snippets/**/*")))
diff --git a/oni-twig/Cask b/oni-twig/Cask
deleted file mode 100644
index ffb9491..0000000
--- a/oni-twig/Cask
+++ /dev/null
@@ -1,8 +0,0 @@
-(source gnu)
-(source melpa)
-
-(package-file "./oni-twig.el")
-
-(files
- "*.el"
- ("snippets" "./snippets/*"))
diff --git a/oni-twig/Eldev b/oni-twig/Eldev
new file mode 100644
index 0000000..1ba3134
--- /dev/null
+++ b/oni-twig/Eldev
@@ -0,0 +1,13 @@
+; -*- mode: emacs-lisp; lexical-binding: t -*-
+
+;; Uncomment some calls below as needed for your project.
+(eldev-use-package-archive 'gnu-elpa)
+;(eldev-use-package-archive 'nongnu-elpa)
+(eldev-use-package-archive 'melpa)
+(eldev-use-package-archive `("oni" . ,(expand-file-name "../bin")))
+
+(eldev-use-plugin 'autoloads)
+
+(setf eldev-files-to-package
+      `(:or ,eldev-files-to-package
+            '("*.el" "./snippets/**/*")))