Calybris Core: a deterministic decision audit engine written in Rust

Calybris Core is an open-source Rust library that records and replays decision logic in a fully deterministic way, giving developers a clear audit trail for any rule-based or automated decision. For indie makers building compliance-sensitive tools, fintech utilities, or anything where 'why did the system decide X' matters, a lightweight auditable decision engine is the kind of infrastructure primitive that usually gets bolted on too late. Shipping it as a standalone, open-source crate lowers that bar considerably.