rippling·Software Engineer·Technical Phone Screen·Intermediate

IntermediatePrefer not to say

Jun 2026Remote

Summary

Phone screen for a software engineering role at Rippling. They gave me an AI coding option and I went with it. The problem was a logger system with multiple configurable behaviors, basically chaining together different output transformations.

Questions Asked (1)

Design and implement a configurable logger system that supports the following operations: removing all occurrences of a specified substring before printing, truncating messages to a maximum character length before printing, uppercasing the entire message before printing, and storing messages to an internal list without printing. Each operation should produce output when invoked.

System DesignAlgorithms & Data StructuresTechnical Trade-offs

Author's notes

The individual pieces aren't that hard but the real question is how you structure them together.

Create a free account to read the full note

AI HintsAI Generated

Suggested Approach

Start by clarifying requirements and defining a clean interface for the logger with configurable operations. Then implement each operation as a separate strategy or decorator, ensuring they can be composed and that each produces output when invoked. Discuss trade-offs between different design patterns and consider extensibility for future operations.

Pro tip: Emphasize the importance of separation of concerns and testability: each operation should be independently testable and easily replaceable. Mention that using a decorator pattern allows dynamic composition of behaviors without modifying the core logger.

1. Clarify Requirements and Constraints

Ask clarifying questions about expected input types, performance requirements, and whether operations should be applied in a specific order. Confirm that each operation should print the transformed message and that storing to internal list should not print.

2. Design the Interface and Class Structure

Define a Logger interface with a method like log(message) and a configuration object or builder to specify which operations to apply. Consider using the Strategy pattern for each operation or a Decorator pattern to wrap the logger.

3. Implement Core Operations

Implement each operation as a separate class or function: RemoveSubstring, Truncate, Uppercase, and StoreToList. Ensure each operation modifies the message appropriately and that the final output is printed (except for StoreToList).

4. Handle Composition and Ordering

Decide on the order of operations (e.g., remove substring, then truncate, then uppercase) and allow configuration to specify which operations to apply. Use a pipeline or chain of responsibility to apply operations sequentially.

5. Discuss Trade-offs and Extensibility

Compare different design approaches (inheritance vs composition, decorator vs strategy) and explain how the chosen design supports adding new operations without modifying existing code. Mention performance considerations for large messages or frequent logging.

Key Points to Mention

Use of design patterns like Strategy, Decorator, or Chain of Responsibility for configurable operations.
Separation of concerns: each operation is a separate module/class, making the system testable and maintainable.
Configuration mechanism: builder pattern or configuration object to specify which operations to apply and their parameters.
Order of operations: define a clear sequence (e.g., remove substring, truncate, uppercase) and allow customization if needed.
Output behavior: each operation should print the transformed message, except StoreToList which appends to an internal list without printing.
Extensibility: how to add new operations (e.g., lowercase, replace) without modifying existing code, adhering to Open/Closed principle.

AI-generated suggestions, not part of the candidate's original notes. May be inaccurate — verify before relying on them.