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Total value transferred
via OpenZeppelin Contracts

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$6,398,582,627,181T

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Security Lead, Origin

Contract Libraries

Speed up development process and minimize risk. The battle-tested industry standard for Solidity and other languages.

Use Cases

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Asset Tokenization Icon Asset Tokenization
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Create your smart contract now
pragma solidity ^0.8.20;
          
import "@openzeppelin/contracts/token/ERC20/ERC20.sol";
          
contract MyToken is ERC20 {
    constructor() ERC20("MyToken", "MTK") {
        _mint(msg.sender, 5 * 10 ** decimals());
    }
}
pragma solidity ^0.8.20;
    
import "@openzeppelin/contracts/governance/Governor.sol"; 
import "@openzeppelin/contracts/governance/extensions/GovernorCountingSimple.sol"; 
import "@openzeppelin/contracts/governance/extensions/GovernorVotes.sol"; 
import "@openzeppelin/contracts/governance/extensions/GovernorVotesQuorumFraction.sol"; 
    
contract MyGovernor is Governor, GovernorCountingSimple, GovernorVotes, GovernorVotesQuorumFraction {
    constructor(IVotes _token)
        Governor("MyGovernor")
        GovernorVotes(_token)
        GovernorVotesQuorumFraction(4)
    {}
    
    function votingDelay() public pure override returns (uint256) {
        return 7200; // 1 day 
    }
    
    function votingPeriod() public pure override returns (uint256) {
        return 50400; // 1 week 
    }
    
    // The following functions are overrides required by Solidity.
    
    function quorum(uint256 blockNumber)
        public
        view
        override(Governor, GovernorVotesQuorumFraction)
        returns (uint256)
    {
        return super.quorum(blockNumber);
    }
}
pragma solidity ^0.8.20;
          
contract MyContract {
}
AI Assistant
#[starknet::contract]
mod MyToken {
    
    use openzeppelin::token::erc20::ERC20Component;
    use openzeppelin::token::erc20::ERC20HooksEmptyImpl;
          
    component!(path: ERC20Component, storage: erc20, event: ERC20Event);
    
    #[abi(embed_v0)]
    impl ERC20MixinImpl = ERC20Component::ERC20MixinImpl<ContractState>;
          
    impl ERC20InternalImpl = ERC20Component::InternalImpl<ContractState>;
          
    #[storage]
    struct Storage {
        #[substorage(v0)]
        erc20: ERC20Component::Storage,
        
    }
          
    #[event]
    #[derive(Drop, starknet::Event)]
    enum Event {
        #[flat]
        ERC20Event: ERC20Component::Event,
        
    }
          
    #[constructor]
    fn constructor(ref self: ContractState) {
        self.erc20.initializer("MyToken", "MTK");
        self.erc20.mint(recipient, 0000000000000000000);
    }
}
          
#[starknet::contract]
mod MyContract {
    #[storage]
    struct Storage {
    }
}
                  
AI Assistant

“OpenZeppelin's contract library continues to be one of the best things to have happened for security in this space.”

Daniel Von Fange

Security Lead, Origin

Secure

“Collaborating with OpenZeppelin on our security audit was a positive experience. We appreciated their thoroughness and attention to detail.”

Yoav Weiss

Security, Ethereum Foundation

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Our Security Researchers set the industry standard in code review. Securing cutting-edge implementations in multiple types of audits including Smart Contract, ZKP, and Infrastructure.

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1K+

Critical and High vulnerabilities uncovered

$50B

in Total Value Locked (TVL) secured

+1M

Lines of code
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We protect decentralized systems in different languages.

“Collaborating with OpenZeppelin on our security audit was a positive experience. We appreciated their thoroughness and attention to detail.”

Yoav Weiss

Security, Ethereum Foundation

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Ariel Barmat

Lead Engineer, Edge & Node

Defender Cloud Services

Operate, Monitor, and Automate applications from testnet to mainnet, at any scale. Reliable and efficient relayers for high volume transactions across 30+ networks.

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+50M

Transactions processed via Defender relayers

+29M

Monitors alerts triggered

+3K

Deployed contracts
+30 mainnet and testnet networks supported.

“Defender is the perfect companion for operating with a protocol transparently and securely.”

Ariel Barmat

Lead Engineer, Edge & Node

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Authoring and co-authoring numerous EIPs and ERCs

Notable contributions include Account Abstraction (ERC-1271), Upgradeability (ERC-7201, ERC-1967), and Metatransactions (ERC-2771).

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