Rippling - Senior Software Engineer (Benefits)

Overview

Interviewed with Rippling for a Senior Software Engineer position in the Benefits team. The interview consisted of an intensive 60-minute coding test focused on system design problems.

Interview Format: Virtual (Zoom + HackerRank) Duration: ~60 minutes Platform: CodePair Format: 4 system design questions (attempt at least 3), plus 1 DSA problem

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Problem 1: API Rate Limiting System

Requirements

• Limit API requests per user (1000 req/hour)
• Support different tiers (Free, Pro, Enterprise)
• Work across multiple API servers
• Low latency (<10ms)
• Handle burst traffic

Approach

• Algorithm: Token Bucket
• Storage: Redis Cluster with Lua scripts
• Atomicity: Lua scripts for race condition prevention

Key Design: Distributed rate limiter using Redis with token bucket algorithm, allowing burst traffic while maintaining smooth rate limiting.

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Problem 2: Employee Onboarding Workflow System

Requirements

• Multi-step workflows (background check → offer → I-9 → benefits)
• Support 10,000+ concurrent workflows
• Parallel and sequential steps
• Human approval steps
• Retries and failures handling
• Audit trail for compliance

Approach

• Architecture: Event-driven with state machine
• Components: Workflow Engine, Step Executor, State Machine DB, Event Queue
• Key Features: YAML workflow definitions, dependency management, retry policies

Key Design: Workflow engine with state machine pattern, supporting complex dependencies and parallel execution.

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Problem 3: Variable Compensation Calculator

Requirements

• Calculate bonuses/commissions for different roles
• Support complex formulas
• Historical data tracking
• What-if analysis
• Tax compliance

Approach

• Expression engine for flexible formulas
• Version control for compensation rules
• Audit trail for compliance
• Cache layer for performance

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Problem 4: DSA - Merge Intervals

Problem

Given a collection of intervals, merge all overlapping intervals.

Approach: Sort by start time, then merge overlapping intervals

Complexity: O(n log n) time, O(1) space

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Key Takeaways

Preparation Time: 2-3 months

Focus Areas:

• System design (rate limiting, workflow engines)
• Distributed systems patterns
• HR Tech domain (payroll, benefits, compliance)
• Event-driven architecture

Interview Style:

• Very collaborative
• Emphasis on system thinking over coding syntax
• Focus on scalability and real-world constraints
• Interviewer actively engaged

What Rippling Values:

• System design skills
• Product thinking and domain understanding
• Clear communication of trade-offs
• Practical solutions over theoretical perfection

Tips:

• Focus heavily on system design
• Understand HR Tech domain
• Practice designing workflow engines and rate limiters
• Attempt at least 3 out of 4 problems
• Use full time wisely
• Think out loud and discuss trade-offs