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CONTRIBUTING

@@ -1,87 +1,89 @@
-Contributing to the tz code and data
+# Contributing to the tz code and data
 
 The time zone database is by no means authoritative: governments
 change timekeeping rules erratically and sometimes with little
 warning, the data entries do not cover all of civil time before
 1970, and undoubtedly errors remain in the code and data.  Feel
 free to fill gaps or fix mistakes, and please email improvements
-to tz@iana.org for use in the future.  In your email, please give
+to <tz@iana.org> for use in the future.  In your email, please give
 reliable sources that reviewers can check.
 
------
-
-Developers can contribute technical changes to the source code and
-data as follows.
+## Contributing technical changes
 
 To email small changes, please run a POSIX shell command like
-'diff -u old/europe new/europe >myfix.patch', and attach
-myfix.patch to the email.
+`diff -u old/europe new/europe >myfix.patch`, and attach
+`myfix.patch` to the email.
 
 For more-elaborate or possibly-controversial changes,
 such as renaming, adding or removing zones, please read
-<https://www.iana.org/time-zones/repository/theory.html> or the file
-theory.html.  It is also good to browse the mailing list archives
-<https://mm.icann.org/pipermail/tz/> for examples of patches that tend
-to work well.  Additions to data should contain commentary citing
-reliable sources as justification.  Citations should use https: URLs
-if available.
+"[Theory and pragmatics of the tz code and
+data](https://www.iana.org/time-zones/repository/theory.html)".
+It is also good to browse the [mailing list
+archives](https://mm.icann.org/pipermail/tz/) for examples of patches
+that tend to work well.  Additions to data should contain commentary
+citing reliable sources as justification.  Citations should use
+"https:" URLs if available.
 
 For changes that fix sensitive security-related bugs, please see the
-file SECURITY.
+distribution's `SECURITY` file.
+
+Please submit changes against either the [latest release of the Time
+Zone Database](https://www.iana.org/time-zones) or the main branch of
+the development repository.  The latter is preferred.
+
+## Sample Git workflow for developing contributions
 
-Please submit changes against either the latest release in
-<https://www.iana.org/time-zones> or the main branch of the development
-repository.  The latter is preferred.  If you use Git the following
-workflow may be helpful:
+If you use Git the following workflow may be helpful:
 
   * Copy the development repository.
 
-      git clone https://github.com/eggert/tz.git
-      cd tz
+		git clone https://github.com/eggert/tz.git
+		cd tz
 
   * Get current with the main branch.
 
-      git checkout main
-      git pull
+		git checkout main
+		git pull
 
   * Switch to a new branch for the changes.  Choose a different
     branch name for each change set.
 
-      git checkout -b mybranch
+		git checkout -b mybranch
 
-  * Sleuth by using 'git blame'.  For example, when fixing data for
-    Africa/Sao_Tome, if the command 'git blame africa' outputs a line
-    '2951fa3b (Paul Eggert 2018-01-08 09:03:13 -0800 1068) Zone
-    Africa/Sao_Tome 0:26:56 - LMT 1884', commit 2951fa3b should
-    provide some justification for the 'Zone Africa/Sao_Tome' line.
+  * Sleuth by using `git blame`.  For example, when fixing data for
+    Africa/Sao_Tome, if the command `git blame africa` outputs a line
+    `2951fa3b (Paul Eggert 2018-01-08 09:03:13 -0800 1068) Zone
+    Africa/Sao_Tome 0:26:56 - LMT 1884`, commit 2951fa3b should
+    provide some justification for the `Zone Africa/Sao_Tome` line.
 
   * Edit source files.  Include commentary that justifies the
     changes by citing reliable sources.
 
   * Debug the changes, e.g.:
 
-      make check
-      make install
-      ./zdump -v America/Los_Angeles
+		make check
+		make install
+		./zdump -v America/Los_Angeles
 
   * For each separable change, commit it in the new branch, e.g.:
 
-      git add northamerica
-      git commit
+		git add northamerica
+		git commit
 
-    See recent 'git log' output for the commit-message style.
+    See recent `git log` output for the commit-message style.
 
-  * Create patch files 0001-*, 0002-*, ...
+  * Create patch files 0001-..., 0002-..., ...
 
-      git format-patch main
+		git format-patch main
 
-  * After reviewing the patch files, send the patches to tz@iana.org
+  * After reviewing the patch files, send the patches to <tz@iana.org>
     for others to review.
 
-      git send-email main
+		git send-email main
 
     For an archived example of such an email, see
-    <https://mm.icann.org/pipermail/tz/2018-February/026122.html>.
+    "[[tz] [PROPOSED] Fix off-by-1 error for Jamaica and T&C before
+    1913](https://mm.icann.org/pipermail/tz/2018-February/026122.html)".
 
   * Start anew by getting current with the main branch again
     (the second step above).