Minjun (Elena) Long

I am a PhD candidate in Computer Science at the University of Virginia, advised by Professor David Evans in the Security Research Group. I am a systems-security researcher interested in how security policies and trust boundaries are represented, evaluated, maintained, and enforced in evolving systems.

My research has examined browser privacy mechanisms, the evolution of operational detection rules, and the gap between intended security guarantees and real system behavior. In recent work, I study how detection logic changes over time in public security repositories, using semantic representations to distinguish meaningful policy changes from superficial rule edits.

I am currently developing research on runtime policy enforcement for AI agents acting on users’ behalf, with a focus on delegated authority, cross-boundary actions, and irreversible effects. Across these areas, I aim to turn ambiguous security concerns into concrete system artifacts, measurable properties, and enforceable controls.

I am seeking research and engineering roles in systems security, AI security, detection engineering, security measurement, and security tooling.

My Chinese name is written as 龙玟君, and I go by Elena in my daily life. I drew my self-portrait on the right with Procreate, celebrating the Year of the Horse (2026).