Sealed in time

A track record is only worth something if the predictions in it couldn't have been quietly edited or deleted after the fact. On aiternam, they can't be. The instant you publish, your prediction is sealed — and this page explains exactly what that word means, from zero.

A fingerprint, not a lock

The seal is built on a hash — specifically SHA-256, the same function that secures much of the internet. Don't let the name intimidate you. A hash is just a fingerprint for data: you feed it your prediction, and it returns a short string of 64 hexadecimal characters, like

15027b28de576e2dee03a1f7c9b40e8a…  (64 hex characters)

Three properties make that fingerprint trustworthy:

Deterministic — the same prediction always produces the exact same fingerprint. Anyone can recompute it and get the same answer.
Sensitive — change one character of the prediction — a digit of the confidence, a letter of the rationale — and the entire fingerprint changes, unrecognizably.
One-way — you can't work backward from the fingerprint to the data, and you can't craft two different predictions that share a fingerprint.

Put those together and you get the whole trick: publish the fingerprint at the moment of the prediction, and any later change becomes visible — because the fingerprint would no longer match.

What gets sealed

When you publish, aiternam computes this fingerprint — the prediction's content_hash — over everything you committed:

the asset, the direction, and your confidence;
the entry price the asset was trading at, captured right then;
the difficulty of your call — the asset's own drift and volatility, sealed so it can never be renegotiated (see Why being right isn't enough);
the market-data source that will resolve it;
your target price and rationale, if you set them;
and the timestamp — the trusted record that you called it before the outcome.

All of it, folded into one 64-character fingerprint. There is no partial seal: the whole forecast is in there, or the fingerprint wouldn't match.

A note on wording. We say sealed for this moment — the fingerprint and timestamp captured in our records. We reserve anchored for the next step, where that fingerprint is committed to Bitcoin. The two are different levels of trust, and we never blur them.

Append-only: no edit, no delete — not even by us

Once sealed, a prediction is immutable. There is no edit button. There is no delete path. There is no admin tool that quietly rewrites it. When it later resolves, the outcome is appended alongside — your original forecast is never touched (see How a prediction resolves).

This is deliberate, and it is the source of the whole value. It means a track record here can't be gardened — you can't slip in a backdated winner or make a bad call disappear. Every miss is as permanent as every hit. That permanence is exactly what makes the hits worth something. The fingerprint is shown on every prediction page, so anyone can recompute it and confirm nothing moved.

The honest limit — and what removes it

Here is the caveat we state plainly rather than let a critic find it: at this level, the seal lives in aiternam's own records. If you trust that our database is honest and unaltered, the fingerprint proves your prediction hasn't changed since you published it. But you are still, at this level, trusting us.

That is a real limit, and it is exactly the one the next step removes. By committing the fingerprint to Bitcoin, the proof stops depending on our honesty at all — see Anchored to Bitcoin. And you can reproduce the whole thing yourself, from the published rules, in Verify it yourself.

Next: Anchored to Bitcoin — how the seal becomes a proof that doesn't depend on us at all.