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CONTRIBUTING.md

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+# Contributing
+
+Everyone is invited to contribute to this project.
+
+**A BIG THANK YOU** to all of those who already made this project more helpful for everyone. 
+
+# Scope
+
+This project is only about generating PDFs from HTML. That HTML can come from either 
+a string (the HTML itself) or a URL (the body of a GET request to that URL).
+Other sources can be SVG (both Chrome and wkhtmltopdf support this), JPEG or 
+anything else that a Webkit-based Browser would display and print to a PDF.
+
+Anything else like preprocessing the input (HTML templating) or postprocessing the PDF 
+(moving it somewhere, glueing it together with other PDFs) apart from encryption 
+(currently done via PDFTK) is not in scope of this project.
+
+See https://github.com/gutschilla/elixir-pdf-server for an example of how to include 
+more functionality by just _importing_ this project.
+
+# Maintainer's duties
+
+1. I will try hard to review every PR or issue in a timely manner (within a few
+   business days, unless I am on vacations). I am a father, husband and do have a 
+   day job so please do not expect ultra-immediate responses.
+2. I will give usable feedback for why I won't accept a PR
+
+# A kind request to contributors
+
+- for any contribution, describe your intentions first
+- if possible, provide tests and documentation with your PR
+- if possible, come up with a PR in the first place
+- comply with https://github.com/christopheradams/elixir_style_guide (I am not dogmatic about this one)
+- be kind and helpful to everyone as I am trying hard to be as well
+
+# On bug reports
+
+- Until now, I didn't feel anyone was unkind or offensive 
+- nor was anybody looking for me to fix his/her code
+
+While this stays that way, I feel there's no need to enforce good manners :-)