A team led by Xu Li released BackUpper, a harness plug‑in for coding agents. It watches every tool call and saves the affected files before they are altered. In tests on RegretBench – 205 real‑world coding tasks where developers later wished they had saved state – BackUpper prevented all regret moments and restored the original state with 92.2% similarity. The system costs roughly $0.014 per task and uses seven times fewer tokens than a self‑backup baseline.
Why it matters
Developers using AI code assistants can avoid losing work and costly re‑writes, because BackUpper makes reversions cheap and reliable.
