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Bitcoin and chains · 18 / 127 · 2 min

The exit window

Some rollups let you leave only after a wait. The wait is the time in which a fraud proof can be posted. Someone may also be able to pause the door.

Leaving can take days
An app bridge May be fastThe designed exit Can be daysA paused door Not a door

Fast in the app is not the same door as the slow exit.

A worked case

Someone bridges for the cheap fees and assumes leaving is a click. The honest exit is a wait. During a halt the click does nothing. The coins are in that system until the wait, or until an admin opens a door.

The wait

An optimistic rollup assumes a posted result is right unless someone challenges it in time. Leaving can take days. The days are the design.

The other door

A bridge in an app can be faster and can be a different set of keys. Fast is not the same door as the slow exit. Read which one you are on.

Days, on purpose

An optimistic rollup posts a result and treats it as right unless a challenge arrives in time. The waiting period is the security. Leaving by that door takes as long as the challenge window. That can be days.

An app can offer a faster bridge. The faster bridge is another set of keys, or another assumption. When that door pauses, the slow door is the one that was always in the design. Read which door you used.

Read it yourself

These links are the record. They are not a recommendation, and they are not instructions. A news story or a court paper can still be wrong about a detail. The check does not change because a famous name is in the story.

Apply the check

Open a question. The line is about this topic. It is not a verdict that anything is safe.

Check yourself

Write it in your own words. The course's answer opens after that. Nothing is sent.

Does a cheap rollup always let you leave in the next block?

After this you can say how long the exit takes, and who can pause it.