← FrontierLab demos

Semantic Time-Travel Debugger

Debug instrumented algorithms and AI-generated traces with semantic breakpoints, frame diffs, contracts, and first-divergence analysis. Everything stays in this browser.

Drop a JSON file here or choose one

No trace loaded

Frame diff

Changes from the previous frame.

Semantic breakpoints

Trace contract

First divergence

Paste an expected/reference trace and compare it with the loaded actual trace.

Quality diagnostics

    Timeline