Hsi-Jen Chang Email & Phone Number

Bellevue, Washington, United States

Accounting Platform Team (Oct 2022 – Jan 2024) Technical lead for the Assurance Wireless Team within the Accounting Platform Team. Collaborated with the functional lead and product owner to oversee the prepaid pipelines.• Tested data pipelines end-to-end, worked with diverse cross-functional teams to troubleshoot data issues, and implemented new features on the platform utilizing DBT Cloud.• Successfully optimized a long-running reporting query from over 4 hours to under 30 minutes without expanding Snowflake warehouse capacity.• Deployed Snowflake schema and data updates via GitLab CI/CD pipelines.• Documented deployment workflows on Confluence and provided training/knowledge sharing to onshore and offshore teams.FAA & Financial Planning Team (Nov 2016 – Oct 2022) Streamlined data processing, automated extensive manual workflows, and ensured data accuracy for forecasting, budgeting, and audit (SOX) purposes.• Revamped a SQL Server data warehouse to centralize T-Mobile's electronic payments, with a primary focus on reducing credit card transaction fees.• Established SSIS ETL pipelines for a FP&A team, resulting in a remarkable reduction of the forecasting cycle from 2 weeks to just 25 minutes.• Developed and maintained self-service and interactive SSRS and PowerBI reports for many finance users to support month-end reporting needs.• Built T-Mobile’s capital planning process with $15B of annual capital spend.

Kirkland, Washington, United States

Resolved bugs, defects, and security vulnerabilities across ATGStores.com, LowesForPros.com, and Lowes.ca websites.• Mitigated security threats identified by security applications and experts.• Optimized T-SQL queries, stored procedures, and database performance.• Led daily stand-ups, intake meetings, grooming sessions, and retrospectives.

Kirkland, Washington, United States

Managed and contributed to the development of back-office web applications for ATGStores.com, overseeing all applications utilized by the Pro Sales Team.• Crafted internal web applications using C#, HTML, CSS, Bootstrap, and jQuery from mockups by the UX specialists.• Engineered C# libraries following N-layer architecture principles, leveraged NUnit and Moq frameworks for unit testing, and integrated Log4Net to facilitate error tracking, debugging, and logging functionalities.• Streamlined marketing email automation through API integrations with Responsys and ExactTarget.

Seattle, Washington, United States