diff --git a/Library/Homebrew/cask/lib/hbc/container.rb b/Library/Homebrew/cask/lib/hbc/container.rb
index 3806df33f6..b3d3041739 100644
--- a/Library/Homebrew/cask/lib/hbc/container.rb
+++ b/Library/Homebrew/cask/lib/hbc/container.rb
@@ -6,7 +6,6 @@ require "hbc/container/bzip2"
 require "hbc/container/cab"
 require "hbc/container/criteria"
 require "hbc/container/dmg"
-require "hbc/container/directory"
 require "hbc/container/executable"
 require "hbc/container/generic_unar"
 require "hbc/container/gpg"
diff --git a/Library/Homebrew/cask/lib/hbc/container/air.rb b/Library/Homebrew/cask/lib/hbc/container/air.rb
index f2ebb6bcd0..daafc8afed 100644
--- a/Library/Homebrew/cask/lib/hbc/container/air.rb
+++ b/Library/Homebrew/cask/lib/hbc/container/air.rb
@@ -3,34 +3,21 @@ require "hbc/container/base"
 module Hbc
   class Container
     class Air < Base
-      INSTALLER_PATHNAME =
-        Pathname("/Applications/Utilities/Adobe AIR Application Installer.app" \
-                 "/Contents/MacOS/Adobe AIR Application Installer")
-
       def self.me?(criteria)
-        %w[.air].include?(criteria.path.extname)
-      end
-
-      def self.installer_cmd
-        return @installer_cmd ||= INSTALLER_PATHNAME if installer_exist?
-        raise CaskError, <<~EOS
-          Adobe AIR runtime not present, try installing it via
-
-              brew cask install adobe-air
-
-        EOS
-      end
-
-      def self.installer_exist?
-        INSTALLER_PATHNAME.exist?
+        criteria.path.extname == ".air"
       end
 
       def extract
-        install = @command.run(self.class.installer_cmd,
-                               args: ["-silent", "-location", @cask.staged_path, Pathname.new(@path).realpath])
+        unpack_dir = @cask.staged_path
 
-        return unless install.exit_status == 9
-        raise CaskError, "Adobe AIR application #{@cask} already exists on the system, and cannot be reinstalled."
+        @command.run!(
+          "/Applications/Utilities/Adobe AIR Application Installer.app/Contents/MacOS/Adobe AIR Application Installer",
+          args: ["-silent", "-location", unpack_dir, path],
+        )
+      end
+
+      def dependencies
+        @dependencies ||= [CaskLoader.load("adobe-air")]
       end
     end
   end
diff --git a/Library/Homebrew/cask/lib/hbc/container/base.rb b/Library/Homebrew/cask/lib/hbc/container/base.rb
index 78610a1ab5..61de19d1b2 100644
--- a/Library/Homebrew/cask/lib/hbc/container/base.rb
+++ b/Library/Homebrew/cask/lib/hbc/container/base.rb
@@ -1,6 +1,8 @@
 module Hbc
   class Container
     class Base
+      attr_reader :path
+
       def initialize(cask, path, command, nested: false, verbose: false)
         @cask = cask
         @path = path
@@ -41,6 +43,10 @@ module Hbc
 
         true
       end
+
+      def dependencies
+        []
+      end
     end
   end
 end
diff --git a/Library/Homebrew/cask/lib/hbc/container/bzip2.rb b/Library/Homebrew/cask/lib/hbc/container/bzip2.rb
index efa95376a2..9e06d68900 100644
--- a/Library/Homebrew/cask/lib/hbc/container/bzip2.rb
+++ b/Library/Homebrew/cask/lib/hbc/container/bzip2.rb
@@ -4,13 +4,13 @@ module Hbc
   class Container
     class Bzip2 < Base
       def self.me?(criteria)
-        criteria.magic_number(/^BZh/n)
+        criteria.magic_number(/\ABZh/n)
       end
 
       def extract
         Dir.mktmpdir do |unpack_dir|
-          @command.run!("/usr/bin/ditto",   args: ["--", @path, unpack_dir])
-          @command.run!("/usr/bin/bunzip2", args: ["--quiet", "--", Pathname.new(unpack_dir).join(@path.basename)])
+          @command.run!("/usr/bin/ditto", args: ["--", @path, unpack_dir])
+          @command.run!("bunzip2", args: ["--quiet", "--", Pathname.new(unpack_dir).join(@path.basename)])
 
           extract_nested_inside(unpack_dir)
         end
diff --git a/Library/Homebrew/cask/lib/hbc/container/cab.rb b/Library/Homebrew/cask/lib/hbc/container/cab.rb
index 0a6411b7e6..d128aa05d3 100644
--- a/Library/Homebrew/cask/lib/hbc/container/cab.rb
+++ b/Library/Homebrew/cask/lib/hbc/container/cab.rb
@@ -4,19 +4,21 @@ module Hbc
   class Container
     class Cab < Base
       def self.me?(criteria)
-        criteria.magic_number(/^(MSCF|MZ)/n)
+        criteria.magic_number(/\A(MSCF|MZ)/n)
       end
 
       def extract
-        unless cabextract = which("cabextract", PATH.new(ENV["PATH"], HOMEBREW_PREFIX/"bin"))
-          raise CaskError, "Expected to find cabextract executable. Cask '#{@cask}' must add: depends_on formula: 'cabextract'"
-        end
-
         Dir.mktmpdir do |unpack_dir|
-          @command.run!(cabextract, args: ["-d", unpack_dir, "--", @path])
+          @command.run!("cabextract",
+                        args: ["-d", unpack_dir, "--", @path],
+                        env: { "PATH" => PATH.new(Formula["cabextract"].opt_bin, ENV["PATH"]) })
           @command.run!("/usr/bin/ditto", args: ["--", unpack_dir, @cask.staged_path])
         end
       end
+
+      def dependencies
+        @dependencies ||= [Formula["cabextract"]]
+      end
     end
   end
 end
diff --git a/Library/Homebrew/cask/lib/hbc/container/criteria.rb b/Library/Homebrew/cask/lib/hbc/container/criteria.rb
index 52f171d6a1..79e58a1f1a 100644
--- a/Library/Homebrew/cask/lib/hbc/container/criteria.rb
+++ b/Library/Homebrew/cask/lib/hbc/container/criteria.rb
@@ -16,7 +16,7 @@ module Hbc
         return false if path.directory?
 
         # 262: length of the longest regex (currently: Hbc::Container::Tar)
-        @magic_number ||= File.open(path, "rb") { |f| f.read(262) }
+        @magic_number ||= File.binread(path, 262)
         @magic_number.match?(regex)
       end
     end
diff --git a/Library/Homebrew/cask/lib/hbc/container/directory.rb b/Library/Homebrew/cask/lib/hbc/container/directory.rb
deleted file mode 100644
index e4bb1095b2..0000000000
--- a/Library/Homebrew/cask/lib/hbc/container/directory.rb
+++ /dev/null
@@ -1,24 +0,0 @@
-require "hbc/container/base"
-
-module Hbc
-  class Container
-    class Directory < Base
-      def self.me?(*)
-        false
-      end
-
-      def extract
-        @path.children.each do |child|
-          next if skip_path?(child)
-          FileUtils.cp child, @cask.staged_path
-        end
-      end
-
-      private
-
-      def skip_path?(*)
-        false
-      end
-    end
-  end
-end
diff --git a/Library/Homebrew/cask/lib/hbc/container/dmg.rb b/Library/Homebrew/cask/lib/hbc/container/dmg.rb
index fcb9b5739d..c34b80fed6 100644
--- a/Library/Homebrew/cask/lib/hbc/container/dmg.rb
+++ b/Library/Homebrew/cask/lib/hbc/container/dmg.rb
@@ -15,7 +15,7 @@ module Hbc
       def extract
         mount do |mounts|
           begin
-            raise CaskError, "No mounts found in '#{@path}'; perhaps it is a bad DMG?" if mounts.empty?
+            raise CaskError, "No mounts found in '#{@path}'; perhaps it is a bad disk image?" if mounts.empty?
             mounts.each(&method(:extract_mount))
           ensure
             mounts.each(&method(:eject))
diff --git a/Library/Homebrew/cask/lib/hbc/container/executable.rb b/Library/Homebrew/cask/lib/hbc/container/executable.rb
index af3b36fd10..286f435622 100644
--- a/Library/Homebrew/cask/lib/hbc/container/executable.rb
+++ b/Library/Homebrew/cask/lib/hbc/container/executable.rb
@@ -5,7 +5,7 @@ module Hbc
   class Container
     class Executable < Naked
       def self.me?(criteria)
-        return true if criteria.magic_number(/^#!\s*\S+/)
+        return true if criteria.magic_number(/\A#!\s*\S+/n)
 
         begin
           criteria.path.file? && MachO.open(criteria.path).header.executable?
diff --git a/Library/Homebrew/cask/lib/hbc/container/generic_unar.rb b/Library/Homebrew/cask/lib/hbc/container/generic_unar.rb
index 1cc243623a..21cac5a882 100644
--- a/Library/Homebrew/cask/lib/hbc/container/generic_unar.rb
+++ b/Library/Homebrew/cask/lib/hbc/container/generic_unar.rb
@@ -3,22 +3,20 @@ require "hbc/container/base"
 module Hbc
   class Container
     class GenericUnar < Base
-      def self.me?(criteria)
-        return false unless lsar = which("lsar", PATH.new(ENV["PATH"], HOMEBREW_PREFIX/"bin"))
-        criteria.command.run(lsar,
-                             args:         ["-l", "-t", "--", criteria.path],
-                             print_stderr: false).stdout.chomp.end_with?("passed, 0 failed.")
+      def self.me?(_criteria)
+        false
       end
 
       def extract
-        unless unar = which("unar", PATH.new(ENV["PATH"], HOMEBREW_PREFIX/"bin"))
-          raise CaskError, "Expected to find unar executable. Cask #{@cask} must add: depends_on formula: 'unar'"
-        end
+        unpack_dir = @cask.staged_path
 
-        Dir.mktmpdir do |unpack_dir|
-          @command.run!(unar, args: ["-force-overwrite", "-quiet", "-no-directory", "-output-directory", unpack_dir, "--", @path])
-          @command.run!("/usr/bin/ditto", args: ["--", unpack_dir, @cask.staged_path])
-        end
+        @command.run!("unar",
+                      args: ["-force-overwrite", "-quiet", "-no-directory", "-output-directory", unpack_dir, "--", path],
+                      env: { "PATH" => PATH.new(Formula["unar"].opt_bin, ENV["PATH"]) })
+      end
+
+      def dependencies
+        @dependencies ||= [Formula["unar"]]
       end
     end
   end
diff --git a/Library/Homebrew/cask/lib/hbc/container/gpg.rb b/Library/Homebrew/cask/lib/hbc/container/gpg.rb
index 273e722bf2..4c3a4925a1 100644
--- a/Library/Homebrew/cask/lib/hbc/container/gpg.rb
+++ b/Library/Homebrew/cask/lib/hbc/container/gpg.rb
@@ -18,22 +18,26 @@ module Hbc
           ["--fetch-key", @cask.gpg.key_url.to_s]
         end
 
-        @command.run!("gpg", args: args)
+        @command.run!("gpg",
+                      args: args,
+                      env: { "PATH" => PATH.new(Formula["gnupg"].opt_bin, ENV["PATH"]) })
       end
 
       def extract
-        unless gpg = which("gpg", PATH.new(ENV["PATH"], HOMEBREW_PREFIX/"bin"))
-          raise CaskError, "Expected to find gpg executable. Cask '#{@cask}' must add: depends_on formula: 'gpg'"
-        end
-
         import_key
 
         Dir.mktmpdir do |unpack_dir|
-          @command.run!(gpg, args: ["--batch", "--yes", "--output", Pathname(unpack_dir).join(@path.basename(".gpg")), "--decrypt", @path])
+          @command.run!("gpg",
+                        args: ["--batch", "--yes", "--output", Pathname(unpack_dir).join(@path.basename(".gpg")), "--decrypt", @path],
+                        env: { "PATH" => PATH.new(Formula["gnupg"].opt_bin, ENV["PATH"]) })
 
           extract_nested_inside(unpack_dir)
         end
       end
+
+      def dependencies
+        @dependencies ||= [Formula["gnupg"]]
+      end
     end
   end
 end
diff --git a/Library/Homebrew/cask/lib/hbc/container/gzip.rb b/Library/Homebrew/cask/lib/hbc/container/gzip.rb
index 4c76de4bb0..a98f1d1d1a 100644
--- a/Library/Homebrew/cask/lib/hbc/container/gzip.rb
+++ b/Library/Homebrew/cask/lib/hbc/container/gzip.rb
@@ -4,13 +4,13 @@ module Hbc
   class Container
     class Gzip < Base
       def self.me?(criteria)
-        criteria.magic_number(/^\037\213/n)
+        criteria.magic_number(/\A\037\213/n)
       end
 
       def extract
         Dir.mktmpdir do |unpack_dir|
-          @command.run!("/usr/bin/ditto",  args: ["--", @path, unpack_dir])
-          @command.run!("/usr/bin/gunzip", args: ["--quiet", "--name", "--", Pathname.new(unpack_dir).join(@path.basename)])
+          @command.run!("/usr/bin/ditto", args: ["--", @path, unpack_dir])
+          @command.run!("gunzip", args: ["--quiet", "--name", "--", Pathname.new(unpack_dir).join(@path.basename)])
 
           extract_nested_inside(unpack_dir)
         end
diff --git a/Library/Homebrew/cask/lib/hbc/container/lzma.rb b/Library/Homebrew/cask/lib/hbc/container/lzma.rb
index 8059d38d1c..70f2dce459 100644
--- a/Library/Homebrew/cask/lib/hbc/container/lzma.rb
+++ b/Library/Homebrew/cask/lib/hbc/container/lzma.rb
@@ -4,20 +4,22 @@ module Hbc
   class Container
     class Lzma < Base
       def self.me?(criteria)
-        criteria.magic_number(/^\]\000\000\200\000/n)
+        criteria.magic_number(/\A\]\000\000\200\000/n)
       end
 
       def extract
-        unless unlzma = which("unlzma", PATH.new(ENV["PATH"], HOMEBREW_PREFIX/"bin"))
-          raise CaskError, "Expected to find unlzma executable. Cask '#{@cask}' must add: depends_on formula: 'lzma'"
-        end
-
         Dir.mktmpdir do |unpack_dir|
           @command.run!("/usr/bin/ditto", args: ["--", @path, unpack_dir])
-          @command.run!(unlzma, args: ["-q", "--", Pathname(unpack_dir).join(@path.basename)])
+          @command.run!("unlzma",
+                        args: ["-q", "--", Pathname(unpack_dir).join(@path.basename)],
+                        env: { "PATH" => PATH.new(Formula["unlzma"].opt_bin, ENV["PATH"]) })
           @command.run!("/usr/bin/ditto", args: ["--", unpack_dir, @cask.staged_path])
         end
       end
+
+      def dependencies
+        @dependencies ||= [Formula["unlzma"]]
+      end
     end
   end
 end
diff --git a/Library/Homebrew/cask/lib/hbc/container/otf.rb b/Library/Homebrew/cask/lib/hbc/container/otf.rb
index 823d04f74e..428545d569 100644
--- a/Library/Homebrew/cask/lib/hbc/container/otf.rb
+++ b/Library/Homebrew/cask/lib/hbc/container/otf.rb
@@ -4,7 +4,7 @@ module Hbc
   class Container
     class Otf < Naked
       def self.me?(criteria)
-        criteria.magic_number(/^OTTO/n)
+        criteria.magic_number(/\AOTTO/n)
       end
     end
   end
diff --git a/Library/Homebrew/cask/lib/hbc/container/pkg.rb b/Library/Homebrew/cask/lib/hbc/container/pkg.rb
index b5f5daad84..bed9aa4839 100644
--- a/Library/Homebrew/cask/lib/hbc/container/pkg.rb
+++ b/Library/Homebrew/cask/lib/hbc/container/pkg.rb
@@ -5,8 +5,7 @@ module Hbc
     class Pkg < Naked
       def self.me?(criteria)
         criteria.extension(/m?pkg$/) &&
-          (criteria.path.directory? ||
-           criteria.magic_number(/^xar!/n))
+          (criteria.path.directory? || criteria.magic_number(/\Axar!/n))
       end
     end
   end
diff --git a/Library/Homebrew/cask/lib/hbc/container/rar.rb b/Library/Homebrew/cask/lib/hbc/container/rar.rb
index 81481f84bd..515f3ce160 100644
--- a/Library/Homebrew/cask/lib/hbc/container/rar.rb
+++ b/Library/Homebrew/cask/lib/hbc/container/rar.rb
@@ -2,11 +2,21 @@ require "hbc/container/generic_unar"
 
 module Hbc
   class Container
-    class Rar < GenericUnar
+    class Rar
       def self.me?(criteria)
-        criteria.magic_number(/^Rar!/n) &&
+        criteria.magic_number(/\ARar!/n) &&
           super
       end
+
+      def extract
+        path = @path
+        unpack_dir = @cask.staged_path
+        @command.run!(Formula["unrar"].opt_bin/"unrar", args: ["x", "-inul", path, unpack_dir])
+      end
+
+      def dependencies
+        @dependencies ||= [Formula["unrar"]]
+      end
     end
   end
 end
diff --git a/Library/Homebrew/cask/lib/hbc/container/seven_zip.rb b/Library/Homebrew/cask/lib/hbc/container/seven_zip.rb
index d1839907cd..6938d77b20 100644
--- a/Library/Homebrew/cask/lib/hbc/container/seven_zip.rb
+++ b/Library/Homebrew/cask/lib/hbc/container/seven_zip.rb
@@ -4,9 +4,19 @@ module Hbc
   class Container
     class SevenZip < GenericUnar
       def self.me?(criteria)
-        # TODO: cover self-extracting archives
-        criteria.magic_number(/^7z/n) &&
-          super
+        criteria.magic_number(/\A7z\xBC\xAF\x27\x1C/n)
+      end
+
+      def extract
+        unpack_dir = @cask.staged_path
+
+        @command.run!("7zr",
+                      args: ["x", "-y", "-bd", "-bso0", path, "-o#{unpack_dir}"],
+                      env: { "PATH" => PATH.new(Formula["p7zip"].opt_bin, ENV["PATH"]) })
+      end
+
+      def dependencies
+        @dependencies ||= [Formula["p7zip"]]
       end
     end
   end
diff --git a/Library/Homebrew/cask/lib/hbc/container/sit.rb b/Library/Homebrew/cask/lib/hbc/container/sit.rb
index c486a981c3..68cdd821a2 100644
--- a/Library/Homebrew/cask/lib/hbc/container/sit.rb
+++ b/Library/Homebrew/cask/lib/hbc/container/sit.rb
@@ -4,8 +4,7 @@ module Hbc
   class Container
     class Sit < GenericUnar
       def self.me?(criteria)
-        criteria.magic_number(/^StuffIt/n) &&
-          super
+        criteria.magic_number(/\AStuffIt/n)
       end
     end
   end
diff --git a/Library/Homebrew/cask/lib/hbc/container/svn_repository.rb b/Library/Homebrew/cask/lib/hbc/container/svn_repository.rb
index cae613b2db..d8795f91d5 100644
--- a/Library/Homebrew/cask/lib/hbc/container/svn_repository.rb
+++ b/Library/Homebrew/cask/lib/hbc/container/svn_repository.rb
@@ -1,14 +1,15 @@
-require "hbc/container/directory"
-
 module Hbc
   class Container
-    class SvnRepository < Directory
+    class SvnRepository < Base
       def self.me?(criteria)
         criteria.path.join(".svn").directory?
       end
 
-      def skip_path?(path)
-        path.basename.to_s == ".svn"
+      def extract
+        path = @path
+        unpack_dir = @cask.staged_path
+
+        @command.run!("svn", args: ["export", "--force", path, unpack_dir])
       end
     end
   end
diff --git a/Library/Homebrew/cask/lib/hbc/container/tar.rb b/Library/Homebrew/cask/lib/hbc/container/tar.rb
index a0a163e13a..6d938ee5ee 100644
--- a/Library/Homebrew/cask/lib/hbc/container/tar.rb
+++ b/Library/Homebrew/cask/lib/hbc/container/tar.rb
@@ -4,16 +4,15 @@ module Hbc
   class Container
     class Tar < Base
       def self.me?(criteria)
-        criteria.magic_number(/^.{257}ustar/n) ||
+        criteria.magic_number(/\A.{257}ustar/n) ||
           # or compressed tar (bzip2/gzip/lzma/xz)
-          IO.popen(["/usr/bin/tar", "-t", "-f", criteria.path.to_s], err: "/dev/null") { |io| !io.read(1).nil? }
+          IO.popen(["/usr/bin/tar", "-t", "-f", criteria.path.to_s], err: File::NULL) { |io| !io.read(1).nil? }
       end
 
       def extract
-        Dir.mktmpdir do |unpack_dir|
-          @command.run!("/usr/bin/tar", args: ["-x", "-f", @path, "-C", unpack_dir])
-          @command.run!("/usr/bin/ditto", args: ["--", unpack_dir, @cask.staged_path])
-        end
+        unpack_dir = @cask.staged_path
+
+        @command.run!("tar", args: ["xf", path, "-C", unpack_dir])
       end
     end
   end
diff --git a/Library/Homebrew/cask/lib/hbc/container/ttf.rb b/Library/Homebrew/cask/lib/hbc/container/ttf.rb
index 612a804f95..cfce72807d 100644
--- a/Library/Homebrew/cask/lib/hbc/container/ttf.rb
+++ b/Library/Homebrew/cask/lib/hbc/container/ttf.rb
@@ -5,9 +5,9 @@ module Hbc
     class Ttf < Naked
       def self.me?(criteria)
         # TrueType Font
-        criteria.magic_number(/^\000\001\000\000\000/n) ||
+        criteria.magic_number(/\A\000\001\000\000\000/n) ||
           # Truetype Font Collection
-          criteria.magic_number(/^ttcf/n)
+          criteria.magic_number(/\Attcf/n)
       end
     end
   end
diff --git a/Library/Homebrew/cask/lib/hbc/container/xar.rb b/Library/Homebrew/cask/lib/hbc/container/xar.rb
index 41eb9f3503..47ac99aee2 100644
--- a/Library/Homebrew/cask/lib/hbc/container/xar.rb
+++ b/Library/Homebrew/cask/lib/hbc/container/xar.rb
@@ -4,14 +4,13 @@ module Hbc
   class Container
     class Xar < Base
       def self.me?(criteria)
-        criteria.magic_number(/^xar!/n)
+        criteria.magic_number(/\Axar!/n)
       end
 
       def extract
-        Dir.mktmpdir do |unpack_dir|
-          @command.run!("/usr/bin/xar", args: ["-x", "-f", @path, "-C", unpack_dir])
-          @command.run!("/usr/bin/ditto", args: ["--", unpack_dir, @cask.staged_path])
-        end
+        unpack_dir = @cask.staged_path
+
+        @command.run!("xar", args: ["-x", "-f", @path, "-C", unpack_dir])
       end
     end
   end
diff --git a/Library/Homebrew/cask/lib/hbc/container/xz.rb b/Library/Homebrew/cask/lib/hbc/container/xz.rb
index 803916490a..2063eaf0e5 100644
--- a/Library/Homebrew/cask/lib/hbc/container/xz.rb
+++ b/Library/Homebrew/cask/lib/hbc/container/xz.rb
@@ -4,19 +4,21 @@ module Hbc
   class Container
     class Xz < Base
       def self.me?(criteria)
-        criteria.magic_number(/^\xFD7zXZ\x00/n)
+        criteria.magic_number(/\A\xFD7zXZ\x00/n)
       end
 
       def extract
-        unless unxz = which("unxz", PATH.new(ENV["PATH"], HOMEBREW_PREFIX/"bin"))
-          raise CaskError, "Expected to find unxz executable. Cask '#{@cask}' must add: depends_on formula: 'xz'"
-        end
+        unpack_dir = @cask.staged_path
+        basename = path.basename
 
-        Dir.mktmpdir do |unpack_dir|
-          @command.run!("/usr/bin/ditto", args: ["--", @path, unpack_dir])
-          @command.run!(unxz, args: ["-q", "--", Pathname(unpack_dir).join(@path.basename)])
-          @command.run!("/usr/bin/ditto", args: ["--", unpack_dir, @cask.staged_path])
-        end
+        @command.run!("/usr/bin/ditto", args: ["--", path, unpack_dir])
+        @command.run!("xz",
+                      args: ["-q", "--", unpack_dir/basename],
+                      env: { "PATH" => PATH.new(Formula["xz"].opt_bin, ENV["PATH"]) })
+      end
+
+      def dependencies
+        @dependencies ||= [Formula["xz"]]
       end
     end
   end
diff --git a/Library/Homebrew/cask/lib/hbc/container/zip.rb b/Library/Homebrew/cask/lib/hbc/container/zip.rb
index 8e3cf5b2dc..42c5e5f84f 100644
--- a/Library/Homebrew/cask/lib/hbc/container/zip.rb
+++ b/Library/Homebrew/cask/lib/hbc/container/zip.rb
@@ -4,7 +4,7 @@ module Hbc
   class Container
     class Zip < Base
       def self.me?(criteria)
-        criteria.magic_number(/^PK(\003\004|\005\006)/n)
+        criteria.magic_number(/\APK(\003\004|\005\006)/n)
       end
 
       def extract
diff --git a/Library/Homebrew/cask/lib/hbc/installer.rb b/Library/Homebrew/cask/lib/hbc/installer.rb
index eb55c9c941..bb976bc7be 100644
--- a/Library/Homebrew/cask/lib/hbc/installer.rb
+++ b/Library/Homebrew/cask/lib/hbc/installer.rb
@@ -19,7 +19,7 @@ module Hbc
 
     PERSISTENT_METADATA_SUBDIRS = ["gpg"].freeze
 
-    def initialize(cask, command: SystemCommand, force: false, skip_cask_deps: false, binaries: true, verbose: false, require_sha: false, upgrade: false)
+    def initialize(cask, command: SystemCommand, force: false, skip_cask_deps: false, binaries: true, verbose: false, require_sha: false, upgrade: false, installed_as_dependency: false)
       @cask = cask
       @command = command
       @force = force
@@ -29,9 +29,10 @@ module Hbc
       @require_sha = require_sha
       @reinstall = false
       @upgrade = upgrade
+      @installed_as_dependency = installed_as_dependency
     end
 
-    attr_predicate :binaries?, :force?, :skip_cask_deps?, :require_sha?, :upgrade?, :verbose?
+    attr_predicate :binaries?, :force?, :skip_cask_deps?, :require_sha?, :upgrade?, :verbose?, :installed_as_dependency?
 
     def self.print_caveats(cask)
       odebug "Printing caveats"
@@ -47,6 +48,7 @@ module Hbc
       odebug "Hbc::Installer#fetch"
 
       satisfy_dependencies
+
       verify_has_sha if require_sha? && !force?
       download
       verify
@@ -57,6 +59,8 @@ module Hbc
 
       Caskroom.ensure_caskroom_exists
 
+      unpack_dependencies
+
       extract_primary_container
       save_caskfile
     rescue StandardError => e
@@ -140,22 +144,28 @@ module Hbc
       Verify.all(@cask, @downloaded_path)
     end
 
+    def primary_container
+      @primary_container ||= begin
+        container = if @cask.container&.type
+          Container.from_type(@cask.container.type)
+        else
+          Container.for_path(@downloaded_path, @command)
+        end
+
+        container&.new(@cask, @downloaded_path, @command, verbose: verbose?)
+      end
+    end
+
     def extract_primary_container
       odebug "Extracting primary container"
 
-      FileUtils.mkdir_p @cask.staged_path
-      container = if @cask.container&.type
-        Container.from_type(@cask.container.type)
-      else
-        Container.for_path(@downloaded_path, @command)
-      end
-
-      unless container
+      unless primary_container
         raise CaskError, "Uh oh, could not figure out how to unpack '#{@downloaded_path}'"
       end
 
-      odebug "Using container class #{container} for #{@downloaded_path}"
-      container.new(@cask, @downloaded_path, @command, verbose: verbose?).extract
+      odebug "Using container class #{primary_container.class} for #{@downloaded_path}"
+      FileUtils.mkdir_p @cask.staged_path
+      primary_container.extract
     end
 
     def install_artifacts
@@ -200,7 +210,7 @@ module Hbc
       arch_dependencies
       x11_dependencies
       formula_dependencies
-      cask_dependencies unless skip_cask_deps?
+      cask_dependencies unless skip_cask_deps? || installed_as_dependency?
     end
 
     def macos_dependencies
@@ -249,27 +259,21 @@ module Hbc
 
       ohai "Installing Formula dependencies: #{not_installed.map(&:to_s).join(", ")}"
       not_installed.each do |formula|
-        begin
-          old_argv = ARGV.dup
-          ARGV.replace([])
-          FormulaInstaller.new(formula).tap do |fi|
-            fi.installed_as_dependency = true
-            fi.installed_on_request = false
-            fi.show_header = true
-            fi.verbose = verbose?
-            fi.prelude
-            fi.install
-            fi.finish
-          end
-        ensure
-          ARGV.replace(old_argv)
+        FormulaInstaller.new(formula).tap do |fi|
+          fi.installed_as_dependency = true
+          fi.installed_on_request = false
+          fi.show_header = true
+          fi.verbose = verbose?
+          fi.prelude
+          fi.install
+          fi.finish
         end
       end
     end
 
     def cask_dependencies
-      return if @cask.depends_on.cask.empty?
       casks = CaskDependencies.new(@cask)
+      return if casks.empty?
 
       if casks.all?(&:installed?)
         puts "All Cask dependencies satisfied."
@@ -280,7 +284,36 @@ module Hbc
 
       ohai "Installing Cask dependencies: #{not_installed.map(&:to_s).join(", ")}"
       not_installed.each do |cask|
-        Installer.new(cask, binaries: binaries?, verbose: verbose?, skip_cask_deps: true, force: false).install
+        Installer.new(cask, binaries: binaries?, verbose: verbose?, installed_as_dependency: true, force: false).install
+      end
+    end
+
+    def unpack_dependencies
+      formulae = primary_container.dependencies.select { |dep| dep.is_a?(Formula) }
+      casks = primary_container.dependencies.select { |dep| dep.is_a?(Cask) }
+                               .flat_map { |cask| [*CaskDependencies.new(cask), cask] }
+
+      not_installed_formulae = formulae.reject(&:any_version_installed?)
+      not_installed_casks = casks.reject(&:installed?)
+
+      return if (not_installed_formulae + not_installed_casks).empty?
+
+      ohai "Satisfying unpack dependencies"
+
+      not_installed_formulae.each do |formula|
+        FormulaInstaller.new(formula).tap do |fi|
+          fi.installed_as_dependency = true
+          fi.installed_on_request = false
+          fi.show_header = true
+          fi.verbose = verbose?
+          fi.prelude
+          fi.install
+          fi.finish
+        end
+      end
+
+      not_installed_casks.each do |cask|
+        Installer.new(cask, verbose: verbose?, installed_as_dependency: true).install
       end
     end
 
diff --git a/Library/Homebrew/unpack_strategy.rb b/Library/Homebrew/unpack_strategy.rb
index 248de594c1..3e1d582d52 100644
--- a/Library/Homebrew/unpack_strategy.rb
+++ b/Library/Homebrew/unpack_strategy.rb
@@ -238,7 +238,7 @@ class RarUnpackStrategy < UnpackStrategy
   private
 
   def extract_to_dir(unpack_dir, basename:)
-    safe_system "unrar", "x", "-inul", path, unpack_dir
+    safe_system Formula["unrar"].opt_bin/"unrar", "x", "-inul", path, unpack_dir
   end
 end