Based on rules.

The rules are certain and cannot be ignored or worked around.

(slang, nonstandard) Alternative form of rules are rules

(programming) A rule by which compilers are allowed to apply any optimizing transformation to a program provided that it makes no change to the observable behavior of the program.

plural of at-rule

(Internet) A type of directive in CSS (Cascading Style Sheets) that is prefixed with the at sign @.

present participle of rule on

Third-person singular simple present indicative form of rule on

simple past tense and past participle of rule on

A surname.