osxbk makes keyboard layouts for OSX.

Usage:
  osxkb FILE
  osxkb -h|-?|--help     To print a help message and exit
  osxkb -v|--version     To print version information and exit

The FILE is a configuration file that tells osxkb what you want to do. The
program generates an OSX bundle containing one or more generated keyboard
layouts. To install it, copy it into your "~/Library/Keyboard Layouts"
directory. You may also have to log out and then before a new keyboard is
available in the System Keyboard Preferences.


THE CONFIGURATION FILE

Here's an annotated example showing all possibilities:

--------------------------------------------------------------------------------
# Lines beginning with # are treated as comments and ignored

# First you configure the bundle as  a whole.

# The bundle's name will be used in the name of the generated .bundle file,
# it can contain anything that's allowed in an OSX filename. This field
# mandatory.
name = NAME

# A URL used to identify the the keyboard(s) to OSX. You're supposed to use
# reverse domain name notation. This field is optional, "org.chinjir" will
# be used as a fallback if you don't supply it.
baseurl = org.chinjir|...

# You can supply a version string if you want, but it's not necessary.
version = VERSION


# Then you configure one or more keyboards, each in its own "keyboard"
# section. The keyboards are completely independent. One possible use is to
# supply both Qwerty and Dvorak variants of a keyboard.
[keyboard]

# You don't have to give the keyboard a name distinct from the bundle's, but
# you can, and if you're configuring multiple keyboards then you'll want
# them to have different names.
name = NAME

# The language will determine where OSX offers the keyboard in the System
# Keyboard Preferences dialog; "en" is the default, and it puts the keyboard
# in the "English" group.
language = en|...

# The base encoding determines the underlying mapping of hardware keys to
# characters. Two encodings are supported internally, ansi.qwerty and
# ansi.dvorak; see below for more on what they do and how to set up your
# own. 
base-encoding = ansi.qwerty|ansi.dvorak|...

# OSX has certain default keybindings that allow you to use the Option key
# to access certain characters (e.g., [Option-e e] gives you "é"). If you
# choose "true" here, those bindings will be included in the generated
# keyboard layout. (The default is "false".)
osxopt = true|false

# This points to a file containing mappings from key sequences to output
# strings. You need to supply at least one such file, you can also repeat
# this option as often as you want.
datafile = FILE

# If you have a CapsLock button, you have a couple of options besides
# leaving it to lock caps. OSX allows you to use CapsLock to switch between
# input methods, to use it that way put "switch-im" here. Alternatively, if
# you set it to "disable" then when CapsLock is down then the keyboard
# layout will fall back on the base encoding (e.g., Qwerty or Dvorak), and
# all special key sequences will be disabled. Omit this option if you just
# want CapsLock to lock caps.
capslock-policy = switch-im|disable

# Supply an .icns file to set the icons that will be used with your keyboard
# layout (in the Keyboard Preferences dialog and the notification area).
# This is optional.
icons = FILE
--------------------------------------------------------------------------------


THE MAIN DATA FILE(s)

You map key sequences to output strings in a simple format, like this:

  é O-e e

This configures the sequence [Option-e e] so that it will result in "é". You
just include a single line in that format for each key sequence you want
treated specially. There are only a few tricks.

First, the key sequences are interpreted relative to the base encoding you
choose---so the "e" in that example represents the key (plus shift state)
that will normally result in "e" (and this is a different key in Qwerty and
Dvorak). This is probably what you want.

Second, use "O-" as a prefix to represent the Option key (so "O-e" means
that you press Option and [e] at the same time). You can also use "C-" for
the Control (*not* Command!) key.

Third, whitespace is ignored, so if you want a literal space or a tab either
in your output or in the key sequence you're defining, you have to use [SPC]
or [TAB] (including the brackets) instead of the literal characters. The
space between the output string and the key sequence is obligatory, but you
don't have to include spaces to break up the key sequences. So this would
work, and be equivalent to the previous example:

  é O-ee

Fourth, some other characters also get aliased, including all nonprinting
characters, as well as - ([DASH]), [ ([LBR]), and ] ([RBR]). The usual
symbolic names for the nonprinting characters all work (see data/ascii.in
for details). Note that a sequence "O-" will always be interpreted as
requiring the Option key; if for some reason you want "O" followed by a
hyphen, then either put a space between them or use "O[DASH]".

For a fuller example, you can look at data/osxopt. It gives OSX's default
bindings in the format required for data files in general.


THE BASE ENCODING

Here's the beginning of the data/ansi.dvorak file that defines the Dvorak
base encoding:

  0 a A A
  1 s S S
  2 d D D
  3 f F F

And here are the corresponding lines in data/ansi.qwerty:

  0 a A A
  1 s S S
  2 d D D
  3 f F F

Each line has four space-delimited fields: the key code, the normal output
when neither Shift nor CapsLock is pressed, the normal output when Shift is
pressed, and the normal output when CapsLock but not Shift is pressed. (The
last two columns will normally differ with nonalphabetic output: [Shift-2]
is "@" but [2] alone when CapsLock is active is just "2".

To define your own base encoding, you just need a file like those. Key codes
can go up to 127, though you don't have to configure all of them; look at
ansi.qwerty or ansi.dvorak to see how it's done. (Pay attention especially
to the treatment of nonprinting characters in the higher code range.)

The encodings that the package supplies use the prefix "ansi" because
they're written for ANSI keyboards. JIS keyboards have a few extra keys, but
I don't have easy access to a JIS keyboard, so I haven't tried to do
anything with those keys. However, it should be easy to set up JIS encodings
if that's what you want.