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+Translations for programs are provided in files with the `.po` suffix. These are
+created by copying PO-template (`.pot`) files, and filling in the missing
+"msgstr" values.
+
+To add a translation, you'll first (1) need to create the `.pot` files if you
+don't already have them, and then (2) copy them and (3) fill them in.
+
+
+## 1. Create the `.pot` files
+
+If you are working from a release source tarball, you can skip this step (the
+`.pot` files are included in the tarball); if you are working from git, read on.
+
+libretools' .pot files are not tracked in git; they are created by running
+`make`.  You'll need a checkout of both 'devtools-par' and 'libretools' to run
+`make` if building from git. The 'devtools-par' and 'libretools' source root
+directories should have the same parent directory.
+
+    $ git clone https://git.parabola.nu/packages/libretools.git/
+    $ git clone https://git.parabola.nu/packages/devtools-par.git/
+    $ cd libretools
+    $ make po/files.generate
+    $ cd po/
+    $ ls
+    gitget.pot
+    librelib.pot
+    libretools.pot
+
+NOTE: If you have modified the libretools source code, that may cause errors
+during translation; especially if you have modified any of the translatable
+strings. The failure will be evident by the error message:
+
+    msgcmp: found N fatal errors
+
+If you see this error, refer to the "Updating translations" section below.
+
+
+## 2. Create the `.po` Files
+
+Create a folder under `po/` with the two-letter language code[^1] you want to
+add.  Then, copy the `.pot` files to that folder, changing the file extension to
+`.po`.  Finally, link the `subdir.mk` file as the Makefile for that directory.
+For example:
+
+    $ mkdir es
+    $ for file in *.pot; do cp $file es/${file%t}; done
+    $ ln -s ../subdir.mk es/Makefile
+
+[^1]: See the langauge code table: <http://www.lingoes.net/en/translator/langcode.htm>
+
+
+## 3. Fill the `.po` Files
+
+From there you can open each .po file in your favorite text editor, and fill in
+the `msgstr` values with translations of the associated `msgid` keys.
+
+
+## 4. Synchronizing/Updating Translations
+
+Normally, the translations are prepared as part of the dist make target
+(the same command used to generate the release source-ball). Eg:
+
+    $ make dist
+
+However, if you have modified the libretools source code significantly or
+modified any translatable strings, it is likely that the `make` command will
+fail, due to the translation files being mis-aligned with the latest changes.
+You will need to run `msgmerge` to merge the newly generated .pot templates
+into the existing .po files, as indicated by the `msgcmp` command traces in
+the build log.
+
+Eg: If the following error message appeers after this log trace:
+
+    msgcmp --use-untranslated --use-fuzzy po/es/libretools.po po/libretools.pot
+    ....
+    msgcmp: found 42 fatal errors
+
+then run:
+
+    $ msgmerge po/es/libretools.po po/libretools.pot
+
+Notice any red (fuzzy) lines. Those are relatively minor mis-matches, which the
+tool was able to reconcile, but may need correction. Also notice any green,
+commented-out, 'msgid'/'msgstr' line pairs. Those are unresolved mis-matches,
+which definitely need correction. They may correspond to a new 'msgid'/'msgstr'
+line pair in the `msgmerge` output, with the new text as 'msgid', and an empty
+'msgstr'; but the changes were too significant for the tool to determine the
+correlation. The standard output of `msgmerge` is the raw text for a new
+replacemnt .po file. Next, direct the output to a file, make the corrections
+to the replacemnt .po file, using the `msgmerge` output as a guide; then replace
+the failed .po file with the new corrected file.
+
+    $ msgmerge po/es/libretools.po po/libretools.pot > po/es/libretools.po-merged
+    $ mv po/es/libretools.po{-merged,}
+
+Alternatively, a merge tool such as `meld`, is especially helpful for this task.
+A merge tool should highlight the same merge conflicts, shown in the the
+`msgmerge` output, as a side-by-side comparison, allowing you to merge the
+changes from the generated '-merged' file, into the tracked .po file, in-place.
+In order to minimize the possible merge conflict next time, it is best to merge
+all of the changes, especially the comments with line numbers.
+
+    $ meld po/es/libretools.po{-merged,}
+
+Once `make clean && make` is able to complete successfully, commit the new .po
+file to the VCS.
+
+    $ git commit -m 'sync translations' po/es/libretools.po