Write Metadata-Aware Code

When you have a certain level of dynamic-ness in your code in almost every case let it be metadata-aware. Let’s imagine you’re converting standard Contact to a custom Contact__c object and you have a field mapping somewhere in your code:

//non-metadata-aware approach 
private static Map<String, String> NON_METADATA_AWARE_FIELD_MAPPING = new Map<String, String> {
    'FirstName' => 'First_Name__c',
    'LastName' => 'Last_Name__c',
    'Email' => 'Email__c'
};
//metadata-aware approach
private static Map<SObjectField, SObjectField> METADATA_AWARE_FIELD_MAPPING = new Map<SObjectField, SObjectField> {
    Contact.FirstName => Contact__c.First_Name__c,
    Contact.LastName => Contact__c.Last_Name__c,
    Contact.Email => Contact__c.Email__c
};

As a pros metadata-aware approach at least minimizes typo errors, allows to leverage “where is this used?” feature and prevent’s accidental deletion of critical elements (fields, objects, etc.).