Software earns trust in layers. First it has to run. Then it has to survive real data, real users, and real operational mistakes. Durable systems are built by people who assume the second layer matters as much as the first.

Durability changes design priorities

A durable design is easier to observe, easier to change, and harder to misunderstand. That often means accepting slightly more upfront structure in exchange for fewer late surprises.

Apex service boundaries should expose intent, not transport detailapex
public with sharing class OrderSyncService {
    public static SyncResult enqueueSync(Set<Id> orderIds) {
        // Coordination happens here; execution happens elsewhere.
        return SyncResult.accepted(orderIds.size());
    }
}

In Salesforce-heavy systems, durability often means being deliberate about bulk behavior, async orchestration, transaction boundaries, and the limits that shape what is safe in production.