This was part 3 of a multi-part problem and it's where things fell apart for me.
Start by clarifying the requirements: what fields can be filtered, what operators are needed, and how filters combine. Then propose a design that fits the existing codebase, such as a filter interface with concrete implementations, and discuss trade-offs like performance, extensibility, and complexity. Walk through a concrete example and outline how you would test it.
Pro tip: Show that you consider the existing architecture and avoid over-engineering; propose the simplest solution that meets current needs but can be extended later. Also, mention how you would handle edge cases like empty filters or invalid inputs.
Ask questions to understand the exact filtering needs: which fields, what operators (equals, contains, range), how multiple filters combine (AND/OR), and any performance constraints.
Identify where filtering should be integrated, what data structures are used, and how to minimize disruption to existing code.
Propose a design, such as a Filter interface with implementations for each operator, or a query builder. Discuss trade-offs between flexibility, performance, and code complexity.
Outline the implementation steps, including how to handle edge cases and how to write unit tests to verify correctness.
Mention how the design supports future filters, and discuss performance implications (e.g., indexing, lazy evaluation) and alternatives.
AI-generated suggestions, not part of the candidate's original notes. May be inaccurate — verify before relying on them.