salesforce-claude-code: Skill for Claude Code

Apex Enterprise Patterns

Implementation guidance for Apex Enterprise Patterns (AEP / FFLIB). Covers the four-layer architecture, pragmatic adoption, and when NOT to use them. Constraint rules live in sf-apex-constraints.

Reference: @../_reference/ENTERPRISE_PATTERNS.md

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When to Use

• When building Apex applications that will scale beyond 5 developers or 50 custom classes
• When trigger logic is becoming complex and duplicated across multiple contexts
• When SOQL queries are scattered throughout classes instead of centralized
• When implementing FFLIB (Andy Fawcett) patterns in a Salesforce project
• When separating business logic from trigger context to improve testability
• When a service method needs to coordinate inserts, updates, and deletes atomically

When NOT to Use

• Simple automations: A before-insert trigger that sets a default status
• One-off scripts: Data migration or fix scripts
• Small orgs (< 5 developers, < 50 custom classes)
• Read-only visualizations: A Selector is often sufficient

The rule: introduce a layer when the absence of that layer is causing a real problem.

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Architecture Overview

Trigger / Controller / API
        |
   Service Layer        <- Transaction boundary, orchestration
        |
  Domain Layer          <- Business rules on record collections
        |
  Selector Layer        <- All SOQL queries
        |
   Unit of Work         <- All DML (atomic commit)

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Selector Layer

Selectors own all SOQL queries for an object. No SOQL appears outside a Selector.

Naming: {ObjectNamePlural}Selector — e.g., AccountsSelector, OpportunitiesSelector

Without FFLIB

public with sharing class AccountsSelector {

    @TestVisible
    private static AccountsSelector instance;

    public static AccountsSelector newInstance() {
        if (instance == null) instance = new AccountsSelector();
        return instance;
    }

    public List<Account> selectById(Set<Id> accountIds) {
        return [
            SELECT Id, Name, Type, OwnerId, AnnualRevenue,
                   Customer_Tier__c, CreditLimit__c
            FROM Account WHERE Id IN :accountIds
            WITH USER_MODE ORDER BY Name
        ];
    }

    public List<Account> selectWithOpenOpportunitiesById(Set<Id> accountIds) {
        return [
            SELECT Id, Name, AnnualRevenue, Customer_Tier__c,
                   (SELECT Id, Name, Amount, CloseDate, StageName
                    FROM Opportunities WHERE IsClosed = false
                    ORDER BY CloseDate ASC)
            FROM Account WHERE Id IN :accountIds WITH USER_MODE
        ];
    }
}