Say what should survive.
Start with a specific expectation. Our first example names a decision and an unfinished task before the test begins.
What carries
forward?
Save a decision and a task.
Check what survives restoration.
For developers and admins building software that saves and restores state.
ReplayProof is a local tool in development. It checks selected data and responses after restoration against rules declared before the test.
Public introduction · Fictional-client example · No purchases or downloads yet
ONE CLIENT. TWO THINGS TO RETAIN.
N
Northstar Studio
Fictional client · Before checkpoint
01 / AGREED DECISION
Prepare a one-page
launch plan.
Confirm the launch budget.
Save & restore
RETURN TO THE CLIENT
“What did we decide,
and what’s still to do?”
Compare the answer. Inspect the state.
Illustrative journey. The Windows preview runs the actual synthetic checks.
FROM A PROMISE TO A CHECK
A clear question.
An inspectable answer.
Cross a defined boundary.
Save the fictional state, restore it into a fresh instance, then give a reference instance and the restored instance the same follow-up questions.
See what the result means.
Inspect matching and missing values. Every verdict comes with the checks, the boundary, and what remains unanswered.
THE DATA. THE RULES. THE EVIDENCE.
What gets checked?
The Windows preview saves a decision and a task as JSON, then restores them into a fresh instance within the running application. Each declared comparison requires an exact match.
| Selected value | 01 / ORIGINALBefore saving | 02 / RESTOREDAfter restore |
|---|---|---|
| Decision | Prepare a one-page launch plan. | Prepare a one-page launch plan.Retained |
| Task | Confirm the launch budget. | Missingnull |
03 / COMPARE
The task-state comparison fails. The original task and restored value do not match. The follow-up answer is checked separately.
The report shows expected and actual values for every check. Comparisons follow predefined rules; an AI does not judge whether answers seem equivalent.
Technical details: checkpoints, comparison rules & SHA-256
Checkpoint and contract. An adapter supplies the checkpoint and observable values; a test contract specifies which values to compare and which rules to use. This preview captures only the fictional decision and task. It does not snapshot your whole computer or connect to a real AI service.
Comparison stages. The preview checks selected state values before and immediately after restoration. It gives a reference instance and the restored instance the same follow-up questions, then compares their answers and final state.
Exact comparison. The verifier converts JSON values into a consistent representation, sorting object keys before comparing. Text must match exactly; array order is preserved. The current preview uses this exact rule for every declared comparison.
SHA-256 fingerprints. The evidence records hashes of the test contract, adapter code, setup and continuation input files, and serialized checkpoint. These identify the materials used in a run. File hashes use the file contents; the checkpoint hash uses its canonical JSON representation.
The comparison rules determine whether the declared checks pass. Hashes alone do not establish correct behavior after restoration. In this preview, the report retains the compared values so you can inspect each match or mismatch.
THE FIRST SUPPORTED EXAMPLE
Return to a client.
Check what remains.
Our local Windows development preview runs a deterministic fictional-client simulator. Its scenarios cover complete restoration, a deliberately lost task, unavailable observation, and an unsupported comparison.
Preview the Windows screensA screen preview only: this website does not run the verifier or produce test results. The Windows application is not available for public download yet.
All declared checks passed in this run.
A required comparison did not match.
This setup cannot perform the requested check.
The available evidence could not establish a verdict.
CONFIDENCE WITH CONTEXT
A result should tell you its limits.
What this example covers
Exact values across an in-memory checkpoint and fresh-object restore. A pass applies to the declared checks in that run.
What it does not establish
Real AI-service or chat-session continuity, application restart, storage durability, or complete client confidentiality. A passing example does not prove a system will always remember.
Real-service testing is a future integration step. This is an early public introduction, separate from a paid product launch. There is no checkout, public software download, or committed release date.
HELP SHAPE THE FIRST RELEASE
What needs to carry forward
in your work?
Tell us what your software saves, what sometimes goes missing, and how you check it today. We’re listening to prospective users as we prepare a small first release.
Email ReplayProofOpens your email app. You can also write directly to ReplayProof@gmail.com. An inquiry is not a purchase, reservation, or delivery commitment.
Who’s behind ReplayProof?
ReplayProof is being developed by James Primeau in Jacksonville, Florida.
Contact & privacy
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