diff --git a/CONTRIBUTIONS.md b/CONTRIBUTIONS.md
index dd032453..e3b17aa3 100644
--- a/CONTRIBUTIONS.md
+++ b/CONTRIBUTIONS.md
@@ -36,4 +36,18 @@ To ensure all pull requests can be easily checked and merged, here are some tips
 * Your code should work on other platforms running the bourne shell (/bin/sh), not just BASH.
 * Properly document your code where needed. Besides the 'what', focus on explaining the 'why'.
 * Check the log information (lynis.log) of your new test or changed code, so that it provides helpful details for others.
-* Most variables should be capitalized, with underscore as word separator (e.g. PROCESS_EXISTS=1)
+
+## Code Guidelines
+
+### General
+Identation should be 4 spaces (no tab character).
+
+### Comments
+Comments: use # sign followed by a space. When needed, create a comment block.
+Blank lines: allowed, one line maximum
+
+### Functions
+All functions use CamelCase to clearly show a difference between shell built-in commands, or external commands.
+
+### Variables
+Variables should be capitalized, with underscore as word separator (e.g. PROCESS_EXISTS=1)