diff --git a/Formula/mksh.rb b/Formula/mksh.rb
new file mode 100644
index 0000000000..24abb92b49
--- /dev/null
+++ b/Formula/mksh.rb
@@ -0,0 +1,23 @@
+require 'formula'
+
+class Mksh < Formula
+  url 'https://www.mirbsd.org/MirOS/dist/mir/mksh/mksh-R40c.cpio.gz'
+  homepage 'https://www.mirbsd.org/mksh.htm'
+  md5 '43a79f721091833bdab3d00fbfe54a14'
+  version '0.40c'
+
+  def install
+    system 'sh ./Build.sh -combine'
+    bin.install 'mksh'
+    man1.install 'mksh.1'
+  end
+
+  def caveats; <<-EOS.undent
+    To allow using mksh as a login shell, run this as root:
+        echo #{HOMEBREW_PREFIX}/bin/mksh >> /etc/shells
+    Then, any user may run
+        chsh
+    to change their shell.
+    EOS
+  end
+end