William Liu Email & Phone Number

San Francisco, California, Us

* Currently redesigning Gusto's data warehouse* Led Gusto's database streaming initiatives, reducing data warehouse latency (24 hours to

San Francisco, California, Us

* Enhanced site reliability by migrating audit data from the main database, leading to 30%+ decrease in database load and marked reduction in site brownouts* Led a major overhaul of our user analytics data pipeline, enhancing system resilience by implementing a dead letter queue that isolates errors without disrupting the entire system. Successfully scaled system from 10 million to 30+ million daily events* Established and manage infrastructure for various critical data tools (e.g. Airflow, Kafka, Kafka Connects, Kubernetes, Lambdas, Redash, Redshift)*Onboarded and mentored engineers across multiple teams, established on-call protocols and paging systems, and enhanced monitoring and alerting capabilities

I developed data extraction, transformation, and loading pipelines.* Rearchitected ETL pipeline from a monolithic app (that used GNUBatch) into a modern scheduling framework (Airflow)* Rewrote calculations for similar home groupings using Python (pandas)* Implemented reproducible development/staging/production environments using Docker, allowing for faster development and testing

Wrocław, Województwo Dolnośląskie, Pl

I developed web applications for early stage startups to large digital innovation centers.* Built APIs (in Django w/ SQL, NoSQL backends) that handled 1M+ active IoT devices* Designed data visualizations (in D3.js) and created Single Page Apps (in AngularJS)* Implemented unit and integration tests, setup infra (in AWS), and CI/CD pipelines

I led the data team for the National Suicide Prevention Lifeline (National), LifeNet (NYC), and DOHMH (NYC) grants.* Programmed ETL scripts (in Python) and web apps for data collection (in Django)* Implemented an automated reporting system, designed reports, and data visualizations* Did statistical data analysis (in R and SPSS) that identified counselor burnout and national call/chat trends

San Diego, California, Us

I used data to help make decisions for business development and customer call center improvements* Analyzed hospital market share, patient experience surveys, and identified trends* Planned, coordinated, and managed software implementations for call center* Helped design and implement ‘Find a Doctor’ website that reduced calls by 33%

San Diego, Ca, Us

I collected and generated reports for San Diego City and County’s homeless shelters and services* Designed reports, monitored data quality, and analyzed trends in homeless services* Provided database administration and technical training to case managers* Assisted with creating a data warehouse used to renew San Diego's HUD funding

Washington, District Of Columbia, Us

I taught technology classes as a Peace Corps Volunteer in the Kingdom of Tonga.* Taught IT classes to NGOs, schools, and businesses* Started and managed the first computer center in Ha’apai* Founded a library with over 10,000 donated books