Cash App: Product PlatformThe Product Platform team’s purpose is to scale product development within Cash’s rapidly growing distributed architecture by building platform APIs that all product services could rely upon for fundamental app experiences. This infrastructure included but was not limited to: a notification sending platform, a centralized API and protocol for syncing historical activity to app clients, and an orchestrator service for in-app product feature requirement resolutions via interactive flows. My role in the organization has varied: I’ve been both an IC and an EM.From August 2020 to August 2021, I served as the engineering manager for a team of 5 engineers within Product Platform. This team was created specifically to see through the migration of a top contributor to scaling runway concerns in the monolith that then powered much of Cash App. We successfully migrated all backend data and logic related to the “activity” view of the transaction types initially launched when Cash App was exclusively driven by a monolith. The conclusion of this project shifted the most resource intensive API and some of the largest database tables from the monolith service to Product Platform’s service offerings already used broadly by product teams. This was a key contribution to the multiyear Cash-wide engineering effort to decompose out of our self hosted monolith into cloud microservice architecture. Upon successfully finishing our mission, the team disbanded and we redistributed back into various parts of Product Platform.

Mobile SecurityEngineer on the team responsible for building the technology that allows Square to ensure that our sellers’ mobile devices are safe for Software PIN in Chip and PIN markets. Full-stack engineering (Java and C) on remote attestation for Android and iOS, back end anti-tamper policy enforcement services, associated data platform, and anomaly detection.* Developed detections (heuristics and ML features) for mobile security threats for Android and iOS* Researched and responded to changes in mobile platforms, threats, and attacks in the wild* Analyzed device telemetry data to detect attacks and identify anomalies* Worked cross-functionally with our mobile client, risk, and hardware teams* Applied cryptographic primitives and protocols to remote attestation and data protectionFurther related reading: https://blog.pcisecuritystandards.org/new-pci-software-pin-entry-on-cots-standard

Internal ProductI contributed features to internal tools used by Square’s risk management, fraud investigation, compliance ops, and support teams. My first major project was a service for managing US customers’ 1099-K tax forms. It also involved collaboration with the data science team to develop a pipeline for generating tax forms. I also built new batch processing infrastructure for recurring screening of new and existing Square businesses.