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+# Issue closing pattern
+
+When a commit or merge request resolves one or more issues, it is possible to automatically have these issues closed when the commit or merge request lands in the project's default branch.
+
+If a commit message or merge request description contains a sentence matching the regular expression below, all issues referenced from
+the matched text will be closed. This happens when the commit is pushed to a project's default branch, or when a commit or merge request is merged into there.
+
+When not specified, the default `issue_closing_pattern` as shown below will be used:
+
+```bash
+((?:[Cc]los(?:e[sd]?|ing)|[Ff]ix(?:e[sd]|ing)?) +(?:(?:issues? +)?%{issue_ref}(?:(?:, *| +and +)?))+)
+```
+
+Here, `%{issue_ref}` is a complex regular expression defined inside GitLab, that matches a reference to a local issue (`#123`), cross-project issue (`group/project#123`) or a link to an issue (`https://gitlab.example.com/group/project/issues/123`).
+
+For example:
+
+```
+git commit -m "Awesome commit message (Fix #20, Fixes #21 and Closes group/otherproject#22). This commit is also related to #17 and fixes #18, #19 and https://gitlab.example.com/group/otherproject/issues/23."
+```
+
+will close `#18`, `#19`, `#20`, and `#21` in the project this commit is pushed to, as well as `#22` and `#23` in group/otherproject. `#17` won't be closed as it does not match the pattern. It also works with multiline commit messages.
+
+Tip: you can test this closing pattern at [http://rubular.com][1]. Use this site
+to test your own patterns.
+Because Rubular doesn't understand `%{issue_ref}`, you can replace this by `#\d+` in testing, which matches only local issue references like `#123`.
+
+## Change the pattern
+
+For Omnibus installs you can change the default pattern in `/etc/gitlab/gitlab.rb`:
+
+```
+issue_closing_pattern: '((?:[Cc]los(?:e[sd]|ing)|[Ff]ix(?:e[sd]|ing)?) +(?:(?:issues? +)?%{issue_ref}(?:(?:, *| +and +)?))+)'
+```
+
+For manual installs you can customize the pattern in [gitlab.yml][0] using the `issue_closing_pattern` key.
+
+[0]: https://gitlab.com/gitlab-org/gitlab-ce/blob/master/config/gitlab.yml.example
+[1]: http://rubular.com/r/Xmbexed1OJ