diff --git a/CodeStyle.md b/CodeStyle.md
new file mode 100644
index 00000000..8210e75c
--- /dev/null
+++ b/CodeStyle.md
@@ -0,0 +1,36 @@
+# Code Style and Conventions
+
+Just  few things that have become important enough to write down. Apart from what is written here
+standard blah applies (ie RoboCop stuff).
+
+## Formatting
+
+### Line Length
+While the days of 80 are over, too big steps seems difficult. I've settled on 100 (ish)
+
+### Hash
+
+I still prefer 1.9 => style , it makes the association more obvious.
+
+## Code style
+
+### Module functions are global
+
+Often one thinks so much in classes that classes get what are basically global functions.
+Global functions are usually meant for a module, so mmodule scope is fitting.
+
+A perfect example are singleton accessors. These are often found clumsily on the classes but
+the code reads much nicer when they are on the module.
+
+### Code generators
+
+Since code is represented by instances of Instructions (and subclasses) the most straightforward
+way of generating code is by new of the Class. This is ok for some.
+
+But often one finds a little massaging of the incoming data is better, while keeping that logic
+out of the Instructions classes. In such cases Module functions are again quite nice. Example:
+
+Instead of GetSlot.new( register, index , register) we use Register.get_slot( name , name , name).
+All names are resolved to registers, or index via Layout. More readable code less repetition.
+
+As the exmple shows, in this case the module function name should be the instruction class name.