PCI-audited transaction systems at bank scale

01Context

Earlier in my career I worked as a senior / lead software engineer at Wells Fargo, on transaction systems that operate under PCI audit. This is the environment that set my reliability standards: enterprise scale, regulated data, and a zero-tolerance bar for the kinds of failures that are merely annoying everywhere else.

02The problem

Financial transaction systems have to be correct, fast, and auditable — all three, all the time. Data has to move reliably between systems, queries have to perform at volume, and every deployment has to survive PCI scrutiny.

03What I did

I built and operated .NET / C# services and the SQL Server data layer behind them, with a focus on the unglamorous engineering that keeps regulated systems trustworthy.

• Engineered .NET / C# services for PCI-audited transaction systems
• Built SSIS data pipelines for reliable cross-system data movement
• Tuned SQL Server queries and schemas for performance at volume
• Optimized SAN storage to keep throughput and cost in line

04Outcome

Transaction systems that passed PCI audit and ran at scale — and a permanent calibration for how production software should behave when the stakes are real. It’s the discipline I bring to every system since, from healthcare platforms to self-learning AI.

5What it adds up to