About Gary Hallmark

Gary Hallmark founded Hallmark AI Consulting to help organizations adopt AI in a practical, controlled, and technically realistic way.

Gary is an MIT graduate and veteran software architect with decades of experience at IBM Research and Oracle. His career has spanned distributed and parallel database technology, SQL standards, middleware, business rules, workflow systems, application integration, SOA, web services, BPM, BPEL, BPMN, and cloud-native enterprise applications. He invented Oracle distributed transaction technology, received Oracle’s first patent, invented Oracle parallel query technology, and later managed Oracle’s advanced database replication project.  

Gary also played a significant role in industry standards. He participated in SQL standards efforts, co-authored the W3C Rule Interchange Format standard, co-chaired the OMG Decision Model and Notation standards committee, co-authored the DMN standard, and invented the DMN FEEL expression language. He also implemented a compliant FEEL interpreter and decision-table service as part of Oracle’s decision modeling work.  

More recently, Gary developed research prototypes for next-generation cloud-native infrastructure for Oracle business and healthcare applications, including work with LLMs, generative AI, agentic healthcare workflows, decision services, business rules, process mining, cloud infrastructure, Python, Jupyter notebooks, and data science tools.  

Hallmark AI Consulting builds on this background to help regulated and data-sensitive organizations evaluate, design, and pilot private AI systems. The firm focuses on practical architectures that combine controlled infrastructure, deterministic workflows, open models, and careful tradeoff analysis across privacy, security, performance, cost, and operational complexity.