---
title: "Circuit changes after the ceremony"
description: "An audit finding, a feature request or a bug fix changes the constraint system after a circuit-specific setup has completed, invalidating the parameters."
type: "failure-mode"
url: "https://zkpick.com/ceremony/failure-modes/circuit-changes-after-the-ceremony/"
section: "04 Running or reusing a trusted setup"
authors:
  - "MarketComp"
publisher: "MarketComp"
version: "1.3"
updated: "2026-09-12"
license: "CC-BY-4.0"
json: "https://zkpick.com/data/ceremony/failure-modes/circuit-changes-after-the-ceremony.json"
---

*By MarketComp. Updated 2026-09-12. Version 1.3. CC BY 4.0.*

# Circuit changes after the ceremony

An audit finding, a feature request or a bug fix changes the constraint system after a circuit-specific setup has completed, invalidating the parameters. Under schedule pressure the change ships against stale parameters, or the ceremony is repeated in a rush with whoever is available.

**Mitigation:** Freeze the circuit and complete the audit before the circuit-specific phase. If a change is unavoidable, repeat the phase properly and treat the timeline slip as the cost of the design choice — or move to a universal setup so this class of event stops being fatal.