Multi-tenant architecture, extensibility and the governor-limit thinking that enterprise SaaS forces on every design.
Salesforce design questions are multi-tenancy questions. One deployment serves many customers with wildly different data volumes, and a single tenant must never be able to degrade another. Expect to discuss isolation strategy, per-tenant quotas, noisy-neighbour containment and why shared infrastructure with hard limits usually beats a deployment per customer.
The second recurring theme is extensibility. The platform is customised by its customers, so designs must accommodate user-defined fields, custom objects and customer-supplied logic without letting any of it break the core. That constraint - build for extension by people you will never talk to - is the distinctive thing the loop tests.
45-60 min
Two rounds at medium difficulty with clean implementation expected.
60 min
Multi-tenant isolation, quotas, extensibility and enterprise reliability.
60 min
Extensible class design - the plugin and customisation problem in miniature.
45 min
Collaboration, customer focus and ownership.
Multi-tenancy as a hard constraint. You are expected to explain how one customer’s workload cannot degrade another’s - quotas, isolation boundaries, fair scheduling - and to justify shared infrastructure with limits over per-customer deployments.
Solid but not extreme. Medium-difficulty problems with an emphasis on correct, readable implementation rather than exotic algorithms. The design rounds usually decide the level.
Because customers extend the platform themselves. Designs have to tolerate user-defined schema and customer-supplied logic without compromising the core, which is a genuinely different problem from designing a closed product.
Practise the rounds Salesforce actually runs, and get scored on where you stand.