From f78e8c50bf8d6956c63cdba25437c9ba89a73a1d Mon Sep 17 00:00:00 2001
From: Michael Weimann <mail@michael-weimann.eu>
Date: Sun, 1 Dec 2019 15:50:31 +0100
Subject: [PATCH] Add CONTRIBUTING.md

---
 CONTRIBUTING.md | 10 ++++++++++
 README.md       |  2 ++
 2 files changed, 12 insertions(+)
 create mode 100644 CONTRIBUTING.md

diff --git a/CONTRIBUTING.md b/CONTRIBUTING.md
new file mode 100644
index 00000000..9a1dee53
--- /dev/null
+++ b/CONTRIBUTING.md
@@ -0,0 +1,10 @@
+# Contributing
+
+## Code style
+
+* Make sure your code follows the [PSR-12](https://www.php-fig.org/psr/psr-12/) code style.
+You may use `composer run phpcs` to verify that.
+* Use `use` statements wherever possible instead of writing the fully qualified name.
+* Order the composer/npm dependencies alphabetically.
+* Do not use code from the [includes](./includes) directory anywhere else.
+* If possible cover your code by test cases.
diff --git a/README.md b/README.md
index 0d0db7c6..419712c9 100644
--- a/README.md
+++ b/README.md
@@ -87,6 +87,8 @@ Since the engelsystem is open source, you can help to improve the system. We rea
 
 Please create single pull requests for every feature instead of creating one big monster of pull request containing a complete rewrite.
 
+Please read the [CONTRIBUTING.md](./CONTRIBUTING.md) before you start.
+
 ### Testing
 To run the unit tests use
 ```bash