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Welcome, Tomás · 1 of 3
You can't buy these keys.
Every key here is minted by passing a real challenge. Not by paying, not by showing up.
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reentrancy
checks, effects,
interactions!
zero it BEFORE the call
Open late · Lagos 23:40
500 keys
LOCK · JAR.SOL
uint a = bal[msg.sender];
bal[msg.sender] = 0;
msg.sender.call{value:a}
line 8 moved up
Adaeze, 34
Tomás, on break
0 keys for sale.
Prove it.
one tile slides,
one key lifts
Evening, Tomás
0 keys · goal: a first dev job · Medellín
This week · Reentrancy Keys
LOCKED
3 of 3 questions, then one real fix.
Try this week's lock
Sunday: Access Control Keys
Opens only to Reentrancy Key holders.
On the bench now
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Reentrancy Keys
Adaeze, Lagos
3 earned of 500
Access Control Keys
Adaeze, Lagos
0 earned of 500
Gas Golf Keys
Priya, Pune
61 earned of 200
Oracle Lock
Kunle, Lagos
0 earned of 300
Indexer Keys
Ines, Lisbon
22 earned of 150
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