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Total value transferred
via OpenZeppelin Contracts
$6,398,582,627,181T
Build
“OpenZeppelin's contract library continues to be one of the best things to have happened for security in this space.”
![](https://www.openzeppelin.com/hs-fs/hubfs/daniel-headshot.png?width=40&height=40&name=daniel-headshot.png)
Daniel Von Fange
Security Lead, Origin
Contract Libraries
Speed up development process and minimize risk. The battle-tested industry standard for Solidity and other languages.
Use Cases
// SPDX-License-Identifier: MIT // Compatible with OpenZeppelin Contracts ^5.0.0 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()); } }
// SPDX-License-Identifier: MIT // Compatible with OpenZeppelin Contracts ^5.0.0 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); } }
// SPDX-License-Identifier: MIT // Compatible with OpenZeppelin Contracts ^5.0.0 pragma solidity ^0.8.20; contract MyContract { }
![AI Assistant](https://www.openzeppelin.com/hs-fs/hubfs/ai-assistant-blob.png?width=348&height=60&name=ai-assistant-blob.png)
// SPDX-License-Identifier: MIT // Compatible with OpenZeppelin Contracts ^5.0.0 #[starknet::contract] mod MyToken { use openzeppelin::introspection::src5::SRC5Component; use openzeppelin::token::erc20::ERC20Component; use openzeppelin::token::erc20::ERC20HooksEmptyImpl; component!(path: ERC20Component, storage: erc20, event: ERC20Event); component!(path: SRC5Component, storage: src5, event: SRC5Event); #[abi(embed_v0)] impl ERC20MixinImpl = ERC20Component::ERC20MixinImpl<ContractState>; impl ERC20InternalImpl = ERC20Component::InternalImpl<ContractState>; #[storage] struct Storage { #[substorage(v0)] erc20: ERC20Component::Storage, #[substorage(v0)] src5: SRC5Component::Storage, } #[event] #[derive(Drop, starknet::Event)] enum Event { #[flat] ERC20Event: ERC20Component::Event, #[flat] SRC5Event: SRC5Component::Event, } #[constructor] fn constructor(ref self: ContractState) { self.erc20.initializer("MyToken", "MTK", ""); self.erc20.mint(recipient, 0000000000000000000); } }
// SPDX-License-Identifier: MIT // Compatible with OpenZeppelin Contracts ^5.0.0 #[starknet::contract] mod MyContract { #[storage] struct Storage { } }
![AI Assistant](https://www.openzeppelin.com/hs-fs/hubfs/ai-assistant-blob.png?width=348&height=60&name=ai-assistant-blob.png)
“OpenZeppelin's contract library continues to be one of the best things to have happened for security in this space.”
![](https://www.openzeppelin.com/hs-fs/hubfs/daniel-headshot.png?width=40&height=40&name=daniel-headshot.png)
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.”
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Yoav Weiss
Security, Ethereum Foundation
Gold Standard Audits
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 codereviewed
“Collaborating with OpenZeppelin on our security audit was a positive experience. We appreciated their thoroughness and attention to detail.”
![](https://www.openzeppelin.com/hs-fs/hubfs/yoav-head.webp?width=40&height=40&name=yoav-head.webp)
Yoav Weiss
Security, Ethereum Foundation
Operate
“Defender is the perfect companion for operating with a protocol transparently and securely.”
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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“Defender is the perfect companion for operating with a protocol transparently and securely.”
![](https://www.openzeppelin.com/hs-fs/hubfs/ariel.png?width=40&height=40&name=ariel.png)
Ariel Barmat
Lead Engineer, Edge & Node
Community Public Goods
Your success is our passion
Our mission is to create and protect the Open Economy.
Our industry-standard development and tooling resources are public, good – and free.
Notable contributions include Account Abstraction (ERC-1271), Upgradeability (ERC-7201, ERC-1967), and Metatransactions (ERC-2771).
The standard for secure smart contract development in Solidity and Cairo. Recognized for its value to the Ethereum ecosystem by leading rankings in RetroPGF 2 and 3. Upgrade plugins for Foundry and Hardhat.
Contributing to the widespread adoption of vulnerability detection and threat response best practices. Members of EthTrust and SEAL911 organizations.
$15+ billion funds at risk saved, helping affected protocols prevent losses.
Supporting top protocols to Build, Secure & Operate onchain
Securing all releases and reducing response time
Smart Contract Security Audits
ZKP Security Audits
Security Advisory
Defender Monitors
Ensuring seamless upgrades and accelerating its developer ecosystem
Contracts library implementation for Stylus
Smart Contract Security Audits
DAO Security Proposal reviews
Defender Deploy, Relayers, Monitors & Actions support for Arbitrum One, Arbitrum Nova & Arbitrum Sepolia
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Smart Contract Security Audits
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DAO Security Proposal Reviews
Defender Monitors, Relayers, Actions
Accelerating their ecosystem with the OpenZeppelin Stack
Parachain runtimes library
Smart Contract Security Audits
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Defender Monitors
Accelerating their ecosystem with the OpenZeppelin Stack
Contracts library implementation for Cairo
Smart Contract Security Audits
Building and expanding its virtual world securely
Smart Contract Security Audits
Security Advisory
Defender Monitors, Actions, Transaction Proposals, Code Inspector