Templater is a small reporting library with a minimal interface. Use your favorite editor (Word, Excel) to create report templates and just fill them with data. It's really as simple as that. Templater is not just a mail-merge library. It supports collections, nested collections and can create very complex reports.

var myFile = "MyDocument.docx";
var data = new { Tag = "a tray" };

using (var document = Configuration.Factory.Open(myFile))
  document.Process(data);

Process.Start(myFile);