diff --git a/Casks/emacs-app-nightly.rb b/Casks/emacs-app-nightly.rb
new file mode 100644
index 00000000..49aa0122
--- /dev/null
+++ b/Casks/emacs-app-nightly.rb
@@ -0,0 +1,59 @@
+# frozen_string_literal: true
+
+cask 'emacs-app-nightly' do
+  version '2021-06-26.b8f9e58.master'
+
+  sha256 'c2a624cac4395541baf36abbd3804f17812fd3cae69e7bd29aea9eee8c58d768'
+  url 'https://github.com/jimeh/emacs-builds/releases/download/Emacs.2021-06-26.b8f9e58.master/Emacs.2021-06-26.b8f9e58.master.macOS-10-15.x86_64.dmg'
+
+  name 'Emacs'
+  desc 'GNU Emacs text editor'
+  homepage 'https://github.com/jimeh/emacs-builds'
+
+  livecheck do
+    url 'https://github.com/jimeh/emacs-builds.git'
+    strategy :git do |tags|
+      tags.map do |tag|
+        tag.gsub(/^Emacs.(\d{4}-\d{2}-\d{2}\.\w+\.master)$/i, '\\1')
+      end.compact
+    end
+  end
+
+  conflicts_with(
+    cask: %w[
+      emacs
+      emacs-nightly
+      emacs-pretest
+      emacs-mac
+      emacs-mac-spacemacs-icon
+    ],
+    formula: %w[
+      emacs
+      emacs-mac
+    ]
+  )
+
+  depends_on macos: '>= :catalina'
+  depends_on arch: :intel
+
+  app 'Emacs.app'
+  binary "#{appdir}/Emacs.app/Contents/MacOS/bin/ebrowse"
+  binary "#{appdir}/Emacs.app/Contents/MacOS/bin/emacs"
+  binary "#{appdir}/Emacs.app/Contents/MacOS/bin/emacsclient"
+  binary "#{appdir}/Emacs.app/Contents/MacOS/bin/etags"
+  binary "#{appdir}/Emacs.app/Contents/Resources/include/emacs-module.h",
+         target: "#{HOMEBREW_PREFIX}/include/emacs-module.h"
+  binary "#{appdir}/Emacs.app/Contents/Resources/site-lisp/subdirs.el",
+         target: "#{HOMEBREW_PREFIX}/share/emacs/site-lisp/subdirs.el"
+
+  manpage "#{appdir}/Emacs.app/Contents/Resources/man/man1/ebrowse.1.gz"
+  manpage "#{appdir}/Emacs.app/Contents/Resources/man/man1/emacs.1.gz"
+  manpage "#{appdir}/Emacs.app/Contents/Resources/man/man1/emacsclient.1.gz"
+  manpage "#{appdir}/Emacs.app/Contents/Resources/man/man1/etags.1.gz"
+
+  zap trash: [
+    '~/Library/Caches/org.gnu.Emacs',
+    '~/Library/Preferences/org.gnu.Emacs.plist',
+    '~/Library/Saved Application State/org.gnu.Emacs.savedState'
+  ]
+end
diff --git a/templates/emacs-app-nightly.rb.tpl b/templates/emacs-app-nightly.rb.tpl
new file mode 100644
index 00000000..7d0df00c
--- /dev/null
+++ b/templates/emacs-app-nightly.rb.tpl
@@ -0,0 +1,60 @@
+# frozen_string_literal: true
+
+cask 'emacs-app-nightly' do
+  version '{{ .Version }}'
+
+  sha256 '{{ .SHA256 "macOS-10-15.x86_64" }}'
+  url '{{ .DownloadURL "macOS-10-15.x86_64" }}'
+
+  name 'Emacs'
+  desc 'GNU Emacs text editor'
+  homepage 'https://github.com/jimeh/emacs-builds'
+
+  livecheck do
+    url 'https://github.com/jimeh/emacs-builds.git'
+    strategy :git do |tags|
+      tags.map do |tag|
+        tag.gsub(/^Emacs.(\d{4}-\d{2}-\d{2}\.\w+\.master)$/i, '\\1')
+      end.compact
+    end
+  end
+
+  conflicts_with(
+    cask: %w[
+      emacs-app
+      emacs
+      emacs-nightly
+      emacs-pretest
+      emacs-mac
+      emacs-mac-spacemacs-icon
+    ],
+    formula: %w[
+      emacs
+      emacs-mac
+    ]
+  )
+
+  depends_on macos: '>= :catalina'
+  depends_on arch: :intel
+
+  app 'Emacs.app'
+  binary "#{appdir}/Emacs.app/Contents/MacOS/bin/ebrowse"
+  binary "#{appdir}/Emacs.app/Contents/MacOS/bin/emacs"
+  binary "#{appdir}/Emacs.app/Contents/MacOS/bin/emacsclient"
+  binary "#{appdir}/Emacs.app/Contents/MacOS/bin/etags"
+  binary "#{appdir}/Emacs.app/Contents/Resources/include/emacs-module.h",
+         target: "#{HOMEBREW_PREFIX}/include/emacs-module.h"
+  binary "#{appdir}/Emacs.app/Contents/Resources/site-lisp/subdirs.el",
+         target: "#{HOMEBREW_PREFIX}/share/emacs/site-lisp/subdirs.el"
+
+  manpage "#{appdir}/Emacs.app/Contents/Resources/man/man1/ebrowse.1.gz"
+  manpage "#{appdir}/Emacs.app/Contents/Resources/man/man1/emacs.1.gz"
+  manpage "#{appdir}/Emacs.app/Contents/Resources/man/man1/emacsclient.1.gz"
+  manpage "#{appdir}/Emacs.app/Contents/Resources/man/man1/etags.1.gz"
+
+  zap trash: [
+    '~/Library/Caches/org.gnu.Emacs',
+    '~/Library/Preferences/org.gnu.Emacs.plist',
+    '~/Library/Saved Application State/org.gnu.Emacs.savedState'
+  ]
+end