blockmindset
Predict, reveal, recalibrate

Blockchain learning loops

Short prediction drills that force the mental model before the explanation. Use them between lessons or before practice sessions.

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Predict Before Reveal

What happens when one character changes?

A block header hash is computed. Then a miner changes one nonce digit and hashes again. Predict how much of the output changes.

Network Intuition

Which transactions enter the next block?

A miner sees more pending transactions than fit in one block. Which transactions are most likely to be selected first?

Attack Model

What gets harder after more confirmations?

A payment has one confirmation, then six confirmations. What changes about a double-spend attempt?

Wallet Safety

What does a signature actually authorize?

A wallet signs a transaction spending 1 BTC to Alice. Can an attacker copy that signature and redirect the payment to Bob?

Security Reflex

Which line should happen before an external call?

A contract owes a user a withdrawal. It can either update the user's balance first or send ETH first. Which is safer?