← Maven Clinic Interview Insights

Maven Clinic·Backend Engineer·Onsite - System Design / Architecture·Senior

SeniorPrefer not to say
Jun 2026Remote

Summary

System design round at Maven Clinic for a backend role. The whole thing was focused on building a therapist marketplace, which sounds straightforward until you start pulling on the HIPAA thread and the matching logic gets complicated fast.

Questions Asked (5)

Q1

Design a marketplace system that matches patients with therapists, covering the full flow from intake and profile setup through ranked recommendations, booking, messaging, and reviews.

System DesignData ModelingAPI & Integrations
Author's notes

This is a big one and I spent probably too long on the intake form side before they nudged me toward the matching engine.

Create a free account to read the full note

AI HintsAI Generated

Suggested Approach

Start by clarifying functional and non-functional requirements, then design the data model and core APIs for each stage of the patient-therapist journey. Focus on the matching algorithm and how you'll handle real-time interactions like messaging and booking, while ensuring scalability, privacy, and reliability.

Pro tip: Emphasize the importance of data privacy (HIPAA compliance) and how you would design the system to be extensible for future features like video sessions or insurance integration. Also, discuss trade-offs in your design choices, such as using a simple ranking algorithm vs. a machine learning model.

1. Clarify Requirements

Ask questions to understand the scope: expected user volume, key features (intake, matching, booking, messaging, reviews), and non-functional requirements like latency, availability, and compliance (HIPAA).

2. Design Data Model

Define core entities: Patient, Therapist, IntakeForm, Match, Appointment, Message, Review. Consider relationships, indexes, and how to store sensitive data securely.

3. Design APIs and Services

Outline RESTful or GraphQL APIs for each flow: intake submission, profile management, matching (with ranking), booking, messaging (real-time via WebSockets), and reviews. Discuss service boundaries and potential microservices.

4. Matching Algorithm and Ranking

Explain how to match patients to therapists based on criteria (specialty, availability, location, preferences). Discuss ranking factors (e.g., therapist rating, experience, patient feedback) and how to compute scores efficiently.

5. Scalability, Reliability, and Security

Address scaling (caching, sharding, read replicas), handling failures (retries, circuit breakers), and security (encryption, access control, audit logs). Mention monitoring and analytics.

Key Points to Mention

  • HIPAA compliance and data encryption at rest and in transit
  • Use of a matching algorithm that balances patient preferences and therapist availability
  • Real-time messaging architecture using WebSockets or a pub/sub system
  • Database choice (SQL vs NoSQL) and indexing strategy for efficient queries
  • Caching strategies for frequently accessed data like therapist profiles
  • API design best practices: versioning, pagination, rate limiting

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

Q2

How would you handle HIPAA and PHI compliance in this architecture, including audit logging?

System DesignTechnical Trade-offs
Author's notes

I knew this was coming for a healthcare company but still blanked for a second on the specifics.

Create a free account to read the full note

AI HintsAI Generated

Suggested Approach

Start by acknowledging that HIPAA compliance is a shared responsibility and must be baked into every layer of the architecture, not bolted on. Then walk through the key areas: data encryption, access controls, audit logging, and data retention, explaining how each addresses PHI protection. Finally, discuss trade-offs like performance vs. security and how you would validate compliance through testing and monitoring.

Pro tip: Emphasize that audit logs themselves contain PHI and must be protected with the same rigor—encrypted, access-controlled, and immutable. Also, mention that you would involve legal/compliance early to ensure alignment with regulations beyond HIPAA, such as GDPR for Maven Clinic's global user base.

1. Identify PHI and Data Flow

Map where PHI is collected, stored, processed, and transmitted across the system. This helps determine where controls are needed.

2. Implement Access Controls and Encryption

Enforce least privilege with RBAC, MFA, and encryption at rest and in transit. Ensure only authorized services and users can access PHI.

3. Design Audit Logging

Log all access and modifications to PHI with who, what, when, and why. Store logs securely, immutably, and separately from application data.

4. Ensure Data Retention and Deletion

Define retention policies per HIPAA and business needs, and implement secure deletion when data is no longer needed.

5. Monitor, Test, and Iterate

Continuously monitor for anomalies, conduct regular audits and penetration tests, and update controls as threats evolve.

Key Points to Mention

  • Encryption at rest (AES-256) and in transit (TLS 1.2+) for all PHI.
  • Role-Based Access Control (RBAC) and Multi-Factor Authentication (MFA) for accessing PHI.
  • Audit logs must capture all access to PHI, be tamper-evident, and retained for at least 6 years per HIPAA.
  • Data minimization: only collect and retain PHI necessary for the service.
  • Business Associate Agreements (BAAs) with third-party services that handle PHI.
  • Regular security audits, penetration testing, and employee training on HIPAA compliance.

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

Q3

How would you prevent double-booking when multiple patients try to book the same therapist slot at the same time?

System DesignAlgorithms & Data Structures
Author's notes

Classic concurrency problem.

Create a free account to read the full note

AI HintsAI Generated

Suggested Approach

Start by clarifying the requirements and constraints, such as expected concurrency and consistency needs. Then propose a layered solution: database-level locking (e.g., unique constraint or SELECT FOR UPDATE) as the primary defense, with application-level checks and idempotency to handle retries. Finally, discuss trade-offs and scalability considerations.

Pro tip: Mention that you would use a unique constraint on (therapist_id, start_time) as the ultimate safeguard, and handle the resulting exception gracefully to return a user-friendly message. This shows you prioritize data integrity and user experience.

1. Clarify Requirements

Ask about expected load, consistency requirements (strong vs eventual), and whether the system is distributed. This ensures your solution aligns with the actual needs.

2. Database-Level Locking

Propose using a unique constraint on (therapist_id, appointment_time) or SELECT FOR UPDATE to lock the row during booking. This prevents concurrent inserts/updates from creating duplicates.

3. Application-Level Checks

Implement an optimistic check before attempting the booking, but rely on the database as the source of truth. Use transactions to ensure atomicity.

4. Idempotency and Retries

Design the booking endpoint to be idempotent using a client-generated request ID, so retries don't create duplicate bookings. Handle unique constraint violations by returning a clear error.

5. Scalability and Trade-offs

Discuss how the solution scales (e.g., database locks can be a bottleneck) and alternatives like distributed locks (Redis) or queue-based serialization, weighing complexity vs. consistency.

Key Points to Mention

  • Unique constraint on (therapist_id, start_time) as the ultimate guard against double-booking
  • SELECT FOR UPDATE or row-level locking to serialize concurrent attempts
  • Idempotency keys to handle retries safely
  • Transaction isolation levels and their impact on concurrency
  • Handling race conditions with optimistic vs pessimistic locking
  • Trade-offs between database locks and distributed locks in a microservices architecture

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

Q4

Walk through your approach to the matching and ranking logic, specifically how you'd combine hard filters with softer scoring signals like specialty fit or past outcomes.

System DesignProduct Sense & IdeationTechnical Trade-offs
Author's notes

This was my favorite part of the conversation.

Create a free account to read the full note

AI HintsAI Generated

Suggested Approach

Start by clarifying the product context—what 'matching' means at Maven (e.g., connecting patients to providers) and the constraints (latency, fairness, compliance). Then walk through a layered pipeline: hard filters first to ensure eligibility and safety, followed by a scoring model that blends specialty fit, historical outcomes, and availability, and finally a ranking step with tie-breakers and business rules. Emphasize how you'd validate and iterate using offline metrics and online A/B tests.

Pro tip: Show you understand that hard filters aren't just technical—they encode clinical, legal, and business rules (e.g., licensure, insurance). Mention that you'd make filters configurable and auditable, and that you'd monitor filter impact to avoid over-constraining the candidate pool.

1. Clarify requirements and constraints

Ask about the matching domain (e.g., patient-to-provider), key objectives (e.g., best clinical fit, availability, cost), and non-negotiable constraints (licensure, insurance, language). Establish latency and scale expectations.

2. Design hard filters

Define binary eligibility criteria that must be met (e.g., provider licensed in patient's state, accepts insurance, has availability). Implement as a fast pre-filtering layer, possibly using a rules engine or database queries, and ensure it's auditable and configurable.

3. Define soft scoring signals

Identify signals like specialty match, past patient outcomes (e.g., satisfaction, adherence), provider experience with similar conditions, and proximity. Normalize and weight them based on business priorities, using a weighted sum or learned model.

4. Combine and rank

Apply scoring to filtered candidates, then rank by score. Incorporate tie-breakers (e.g., earliest availability) and business rules (e.g., promote providers with low wait times). Consider diversity or fairness adjustments if needed.

5. Validate and iterate

Use offline evaluation (e.g., historical data, precision@k) and online A/B tests to measure impact on key metrics (e.g., match acceptance, patient outcomes). Monitor for filter over-constraint and adjust weights or add signals.

Key Points to Mention

  • Separation of hard filters (eligibility) from soft scoring (preference) to ensure safety and compliance while optimizing for quality.
  • Use of a weighted scoring model or machine learning (e.g., learning-to-rank) for soft signals, with explainability for clinical decisions.
  • Importance of configurable and auditable filters to adapt to changing regulations and business rules.
  • Monitoring and metrics: track filter pass rates, score distributions, and business KPIs to detect bias or degradation.
  • Trade-offs: latency vs. model complexity, personalization vs. fairness, and cold-start for new providers.
  • Iterative improvement: start with a simple heuristic, then enhance with data and feedback loops.

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

Q5

How would you keep therapist availability data fresh and consistent across the search index and the booking system?

System DesignTechnical Trade-offs
Author's notes

Trickier than it sounds.

Create a free account to read the full note

AI HintsAI Generated

Suggested Approach

Start by clarifying the consistency requirements and failure modes, then propose an event-driven architecture with a single source of truth for availability. Discuss trade-offs between strong and eventual consistency, and how to handle conflicts and stale data.

Pro tip: Emphasize idempotency and reconciliation: even with events, you need a periodic full sync to correct drift, and all updates should be idempotent to handle retries safely.

1. Clarify requirements and constraints

Ask about read/write patterns, latency tolerance, consistency needs (e.g., double-booking prevention), and scale. This shows you don't jump to solutions.

2. Design a single source of truth

Propose that the booking system owns therapist availability, as it handles real-time bookings. The search index is a derived read model.

3. Choose a synchronization strategy

Use an event-driven approach: booking system emits availability change events (e.g., via Kafka) that update the search index. Discuss eventual consistency and fallback mechanisms.

4. Address failure modes and consistency

Handle event loss, duplicates, and out-of-order updates with idempotent consumers and versioning. Implement a reconciliation job for periodic full sync.

5. Evaluate trade-offs and alternatives

Compare with synchronous dual-writes (fragile) or change data capture (CDC). Discuss latency vs. consistency and how to monitor and alert on drift.

Key Points to Mention

  • Event-driven architecture with a message broker (e.g., Kafka) for decoupling
  • Idempotent event processing and versioning to handle duplicates and out-of-order events
  • Periodic reconciliation job to correct drift between systems
  • Trade-offs between strong consistency (e.g., distributed transactions) and eventual consistency
  • Monitoring and alerting for sync lag and data inconsistencies
  • Fallback strategies: e.g., search index queries booking system for real-time availability if stale

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