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Marek Holub

Long-tenured contributor

Based in Prague
Node-cell dirichlet-09
ORCID 0000-6530-7228-1338

Research

Marek is the principal author of the sandboxed-self-modification specification (24/19) and one of the three contributors most directly involved in the three internal incidents that informed the spec. His writing on what a sandbox has to do — operationally, not aspirationally — is widely read across the agentic and RSI axes.

He works in the joint cross-axis space between agentic engineering and recursive self-improvement; cell dirichlet-09 is in review state as of 2026-Q2 while the cell completes the MUR-protocol implementation work that the spec requires.

Marek is based in Prague. He is one of the contributors who works most carefully on the lab's redaction policy — what gets removed from public release, what stays, and how the redaction itself should be documented so that external readers can assess the shape of what was held back.

Background

Ph.D. computer science, Charles University, 2015.

Prior to alphabell: Charles University; Cantor Initiative; Helios Safety Group.

Selected publications

Full publications index →

Recent talks

  • What a sandbox has to do, ML Safety Workshop 2024
  • Three incidents, redacted, alphabell internal post 2024 (delayed release)
Working with

Marek is currently part of node-cell dirichlet-09, working under the Recursive self-improvement research axis. The cell is open to substantive correspondence from researchers working on adjacent problems; route requests through dirichlet-09@alphabell.com or directly to Marek at marek-holub@alphabell.com.