YouTube Commerce - Billing Core (Full Stack).

Designed, implemented end-to-end, and launched the V2 YouTube frontend Checkout API - powering cart rendering and transaction handling at ~100 QPS, driving $14B+ in annual revenue across 125M+ subscribers for products such as YouTube TV, Primetime Channels, and Channel Memberships. This API uses a modernized catalog model and pricing database, resulting in:

➢ 94% reduction in peak error rate, significantly improving system reliability.

➢ 5 FTEQ/year in engineering velocity and maintenance savings, enabled by reusable modules and reduced code duplication.

➢ 5.3% increase in Sunday Ticket add-on adoption, supporting the US-wide rollout of installment plans and driving monetization.

➢ Scaling of iOS purchase-enabled channels from 4k to over 1 million, driving massive expansion of YouTube Commerce's ecosystem

➢ 19.7% increase in gross revenue and 11.1% growth in purchases globally across all markets for new-to-iOS channels

Core - ALEX (Analytics, Logging, and Experimentation).

Worked on native Android libraries and data pipelines for surfacing core system health metrics for 1st party Google mobile apps (Maps, Search, Photos, Gmail, Drive, etc.) at petabyte scale, driving Google-wide improvements impacting over 3B+ MAUs.

➢ Spearheaded the migration of Boston Dynamics’ primary build system from GN to Bazel by implementing reusable rules for tasks such as generating PEX binaries to be deployed onto the Spot robot and building Python wheels for streamlining in-house dependencies

➢ Implemented an algorithm with TypeScript and Node.js to automatically find and resolve dead links in crawled webpages by parsing and modifying the DOM of dynamically generated HTML

➢ Contributed to Google’s open source repos for Bazel (https://github.com/bazelbuild/bazel/pull/14230) and Bazel build rules for Go (https://github.com/bazelbuild/rules_go/pulls?q=author%3Acvarier+)

➢ Wrote an algorithm in Go for Aspect’s CLI which simpifies Bazel builds by discovering and suggesting common local targets (https://aspect.build/)

➢ Contributed to an increase in revenue generated from clicks of affiliate partner deals in the Yahoo! Mail Android app by implementing deep linking to native 3rd party apps

➢ Worked on a redesign of the shopping feed view - improved cold start time by implementing a local asynchronous SQLite worker to fetch cached emails

➢ Unified the build systems for instrumentation tests on the Snapchat app from a mixture of Buck and Gradle to only Bazel, achieving a 70% reduction in incremental build times, saving over 15 mins of CPU time on average per CI build in production

➢ Implemented a CRON scheduled CI pipeline in Python with Jenkins for catching build-time and test-time regressions in the Snapchat Android production codebase, leading to the timely discovery and resolution of concurrency and linkage errors

➢ Enhanced Snap's test automation client API, written in Kotlin, with asynchronous callbacks for polling and reporting the status of instrumentation tests; using these callbacks, refactored the API, leading to an 80% reduction in LOC

➢ Implemented a CLI client in Kotlin for invoking instrumentation tests remotely through Snap's test automation framework, utilizing the Spoon test runner