Tilde.run provides a secure, transactional, and versioned filesystem sandbox for agentic engineering and AI model experimentation. It allows developers to safely test and iterate on AI agents and models without risking their local development environment or production systems. The transactional nature ensures that experiments can be rolled back, while versioning allows for easy comparison and reproducibility of results. This addresses the growing need for safe and efficient AI development workflows as highlighted by the increasing interest in agentic engineering and language models rebuilding programs.