A.1 The 50/72 RuleA.2 The 80/24 RuleA.3 Arrange Act AssertA.4 BisectionA.5 Checklist for A New Code BaseA.6 Command Query Separation331A.7 Count the VariablesA.8 Cyclomatic ComplexityA.9 Decorators for Cross-Cutting ConcernsA.10 Devil’s AdvocateA.11 Feature FlagA.12 Functional Core, Imperative ShellA.13 Hierarchy of CommunicationA.14 Justify Exceptions from the RuleA.15 Parse, Don’t ValidateA.16 Postel’s LawA.17 Red Green RefactorA.18 Regularly Update DependenciesA.19 Reproduce Defects as TestsA.20 Review CodeA.21 Semantic VersioningA.22 Separate Refactoring of Test and Production CodeA.23 SliceA.24 StranglerA.25 Threat-ModelA.26 Transformation Priority PremiseA.27 X-driven DevelopmentA.28 X Out Names