Design the event instrumentation for Merchant Portal at scale

Problem Statement Description

Product context: DoorDash is a local commerce and delivery platform; its products include restaurant delivery, DashPass, grocery and retail delivery, merchant tools, and dasher tools.

DoorDash’s Merchant Portal is the primary workspace where restaurant, grocery, and local commerce merchants manage menus, store hours, orders, promotions, pricing, payouts, operational issues, and performance insights. For many merchants—especially price-sensitive small and mid-sized operators—the portal is where they decide whether DoorDash is delivering enough ROI to justify commissions, ad spend, discounts, and operational effort.

You are being asked to design the event instrumentation for Merchant Portal at scale. The focus is not on redesigning the portal itself, but on defining how DoorDash should capture reliable, useful, privacy-safe product and business signals across complex merchant workflows. The instrumentation should help product, engineering, analytics, operations, and merchant-facing teams understand behavior, diagnose friction, measure feature adoption, and make better decisions without overloading systems or creating noisy, untrustworthy data.

The system must account for a large and diverse merchant base, multi-location accounts, role-based access, web and mobile surfaces, marketplace-specific workflows, and sensitive commercial data. It should support both near-term product analysis and longer-term platform needs such as experimentation, funnel measurement, alerting, data quality monitoring, and cross-functional reporting.

The experience should consider:

- Core Merchant Portal workflows to instrument, such as onboarding, login, menu updates, order management, store availability, promotions, pricing, reporting, payouts, and support interactions.

- Event taxonomy and naming conventions that remain consistent across surfaces, merchant types, roles, locations, and feature teams.

- Data contracts, required properties, identifiers, timestamps, session context, merchant/account hierarchy, and how events should connect to backend business outcomes.

- Reliability, scalability, latency, deduplication, offline or partial-session behavior, schema evolution, and failure handling for high-volume event streams.

- Privacy, security, access controls, consent, data minimization, and protection of sensitive merchant, financial, operational, and customer-related information.

- Observability for instrumentation health, including missing events, malformed payloads, version drift, sampling decisions, and downstream data quality checks.

- Rollout approach across teams and surfaces, including migration from existing tracking, developer tooling, QA processes, documentation, and governance.

- Product trade-offs between comprehensive tracking, engineering cost, merchant trust, data usability, and marketplace decision-making needs.

Your goal is to define a scalable instrumentation approach that would allow DoorDash to understand and improve the Merchant Portal with confidence, while supporting reliable analytics, experimentation, operational monitoring, and responsible data use across the marketplace.