William Janssen Email & Phone Number

• Built and scaled high-performing teams (35+ reports/60+ total members) responsible for the primary revenue-driving product application, API services, and supporting infrastructure platform to enable >200% growth in active users and data ingestion from March 2022, and 117% YoY revenue increase in 2023.• Manage and empower a group of 8+ direct reports comprised of both people leaders (Engineering Managers) and Individual Contributors (Staff Engineers), helping set career goals and developmental plans.• Responsible for department budget and resourcing in the larger organizational Annual Operating Plan, with monthly, metric-based summaries to the exec team on progress towards committed initiatives.• Oversaw third-party vendor contracts needed by the department, including negotiations leading to ~10% annual cost reduction overall.• Led migration away from legacy NodeJS API services to a modern Graph backed by Kafka, reducing p99 latencies globally by ~100% and total average error rates by >50%.• Formalized and expanded the production support engineer role and software within the organization, reducing hours spent per ticket by 33% in 2023 and a 10% decrease in tickets month to month.

• Responsible for maintaining primary user-facing product application and supporting services that served 2m+ businesses and ~30k MAU.• Developed technical and product strategy for migration away from the legacy AngularJS product, leading to an on-time delivery for MVP pilot group release in a modern, scalable tech stack powered by React. • Successfully migrated >97% of the active user base to the new product application over a 1.5-year time frame via targeted customer segment release strategies while balancing legacy feature parity and new product enhancements, leading to an uplift in conversion rates of ~10-20% and a 14% increase in NPS to a world-class rating.• Created a new Tier 1 support role to reduce the operational burden on the engineering team by ~50%.

Kansas City, Missouri Area

• Responsible for building and maintaining the proprietary software applications and infrastructure critical for the business to function.• Helped introduce and refine the agile process to the development teams to better plan and manage the software lifecycle.• Shared responsibility leading the effort to reverse engineer a proprietary, multi-faceted 30-year-old enterprise Pascal application and rewrite it in a modern technology stack and tooling.• Refactored a node application architecture away from an OO monolith into a more developer-friendly, modular pattern that saved time and effort with developer onboarding and churn on recurring tasks.

Kansas City, Missouri Area

• Consulting architect on multiple client workstreams, providing POVs for architecture decisions and recommendations with reference documentation.• Launching the pilot of an owner rewards program for a Fortune 500 automaker.• Work with client business stakeholders and internal teams to define requirements for projects and provide estimates for the level of effort on high-level milestones.• Part of a team to help foster quality code craftsmanship and ownership via discussion and shared knowledge company-wide.

Kansas City, Missouri Area

- Built custom API for enterprise media distribution platform, and enabledclient to merge two large, legacy applications into one system, saving time andmoney and simplifying workflow.- Migrated 10 years of legacy data and assets into the new application.- In charge of schema rewrite, background processes, and test suite, as well asexposing the new application to several additional existing client web-services.- Administered deployment strategy and server readiness.- Responsible for maintaining a high level of documentation of code and projectstatus , as well as helping scope LOE’s and project timelines.

Tempe, Az

Tempe, Az