Checkpoint 1 / 4
The source and the caption disagree.
The caption says sin⁻¹(x) = 1/sin(x). The checked teaching note distinguishes the inverse sine function from the reciprocal. The release stays blocked while this correction is unresolved.
Independent software project · recorded walkthrough
A correct-looking edit can still leave a broken release.
LessonProof separates a suggestion, a person’s approval, and the checks needed before a change is ready. Here is one real run, from a wrong caption to a verified correction.
0 / 90 seconds
Checkpoint 2 / 4
Review one exact replacement.
The proposed diff changes the caption to sin⁻¹(x) = arcsin(x). It is tied to the current release and exact evidence. A suggestion alone cannot change the release.
Checkpoint 3 / 4
Approval is a separate action.
A person approves the exact diff. The approval is now recorded, but the synthetic caption has not changed yet. Applying a change requires a separate action against the same release state.
Checkpoint 4 / 4
Apply the change and check the result.
The approved caption is replaced, two dependency proof records are recomputed, and all six deterministic checks pass. The release hash changes. Undo is available only against the matching current state.
What I contributed
I defined the problem, product boundaries, human approval model and acceptance criteria. I reviewed and tested AI-assisted implementation, and checked what the release could honestly claim.
What I can discuss in an interview
- Why approval and mutation are separate.
- How exact evidence and an editable-path allowlist bound a change.
- How stale release hashes stop an outdated proposal.
- What automated checks prove, and what they leave to the reviewer.
This is an independent prototype. The checks verify that an approved change is present and its declared dependencies are current. They do not certify mathematical truth or automatically publish teaching materials.
Source revision: 62f132d. Local verification: 42 tests passed, TypeScript and production build passed. One test fixture was adapted to use the Windows temporary directory; application logic was unchanged. The four screenshots record the actual built-in scenario.