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Singleton and config_db Patterns without Global Chaos: Interview Questions

Interview Questions for Singleton and config_db Patterns without Global Chaos.

Interview questions

Q1. Why not replace config_db entirely with singleton access?

Answer: It hides dependencies and removes path-scoped override control, making tests less predictable and harder to debug.

Q2. What does fail-fast config retrieval buy you in UVM?

Answer: Miswired environments fail early with clear diagnostics instead of running with accidental defaults.

Q3. When is singleton still justified in a modern UVM environment?

Answer: When there is truly one run-wide identity/service, but distribution still happens through explicit component boundaries like config_db.

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