# Latest **URL:** https://forum.openzeppelin.com/latest.md [Latest](https://forum.openzeppelin.com/latest.md) · [Categories](https://forum.openzeppelin.com/categories.md) · [Tags](https://forum.openzeppelin.com/tags.md) --- ## [How to verify a contract on Etherscan/BscScan/PolygonScan](https://forum.openzeppelin.com/t/how-to-verify-a-contract-on-etherscan-bscscan-polygonscan/14225)
**Author:** [@frangio](https://forum.openzeppelin.com/u/frangio)\ **Replies:** 73\ **Last updated:** [June 18, 2025, 8:48am UTC](https://forum.openzeppelin.com/t/how-to-verify-a-contract-on-etherscan-bscscan-polygonscan/14225 "2025-06-18T08:48:19Z")
Make sure to read this post before asking a question about verification. If your issue is not addressed here, just leave a comment below. If you want to pay someone to do the verification for you, create a post in Sma… --- ## [Welcome to the OpenZeppelin Community!](https://forum.openzeppelin.com/t/welcome-to-the-openzeppelin-community/235)
**Author:** [@martriay](https://forum.openzeppelin.com/u/martriay)\ **Replies:** 0\ **Last updated:** [January 30, 2019, 11:26pm UTC](https://forum.openzeppelin.com/t/welcome-to-the-openzeppelin-community/235 "2019-01-30T23:26:42Z")
Welcome to the OpenZeppelin Community! This is a public forum for developers to learn, discuss and explore design patterns and best practices about smart contract development. If you have any feedback, we’d love to hea… --- ## [Mitigating Inflation Attacks on an ERC-4626 Freelance Escrow Vault Routing Idle Capital to Aave v3](https://forum.openzeppelin.com/t/mitigating-inflation-attacks-on-an-erc-4626-freelance-escrow-vault-routing-idle-capital-to-aave-v3/45592)
**Author:** [@joop](https://forum.openzeppelin.com/u/joop)\ **Replies:** 0\ **Last updated:** [September 17, 2026, 8:49pm UTC](https://forum.openzeppelin.com/t/mitigating-inflation-attacks-on-an-erc-4626-freelance-escrow-vault-routing-idle-capital-to-aave-v3/45592 "2026-09-17T20:49:49Z")
Hello everyone, I am building a multi-sided marketplace architecture (Trestle DeFi) where idle freelance escrow funds are swept into an ERC-4626 Auto-Yield Vault (routing to external money markets like Aave v3) to keep … --- ## [Example/Tutorial for migrating data from prev version to next version of a smart contract](https://forum.openzeppelin.com/t/example-tutorial-for-migrating-data-from-prev-version-to-next-version-of-a-smart-contract/45557)
**Author:** [@anilhelvaci](https://forum.openzeppelin.com/u/anilhelvaci)\ **Replies:** 0\ **Last updated:** [September 1, 2026, 11:44am UTC](https://forum.openzeppelin.com/t/example-tutorial-for-migrating-data-from-prev-version-to-next-version-of-a-smart-contract/45557 "2026-09-01T11:44:38Z")
Example Scenario Let's imagine I've an upgradeable contract already deployed behind a proxy and the implementation contract fully adopted namespaced storage. After a while one of the structs needs to get a new variable w… --- ## [What is a sufficient test suite to rely on a contract's upgradeability status?](https://forum.openzeppelin.com/t/what-is-a-sufficient-test-suite-to-rely-on-a-contracts-upgradeability-status/45498)
**Author:** [@anilhelvaci](https://forum.openzeppelin.com/u/anilhelvaci)\ **Replies:** 1\ **Last updated:** [September 1, 2026, 11:33am UTC](https://forum.openzeppelin.com/t/what-is-a-sufficient-test-suite-to-rely-on-a-contracts-upgradeability-status/45498 "2026-09-01T11:33:28Z")
Context Hello all :hand\_with\_fingers\_splayed: I'm converting my existing smart contracts to be upgradeable. The process seems fairly straight-forward. However, I can't tell when I can say "this set of smart contracts upg… --- ## [Can you create a BEP20 contract for small fee?](https://forum.openzeppelin.com/t/can-you-create-a-bep20-contract-for-small-fee/26530)
**Author:** [@newdriver](https://forum.openzeppelin.com/u/newdriver)\ **Replies:** 9\ **Last updated:** [August 2, 2026, 7:04pm UTC](https://forum.openzeppelin.com/t/can-you-create-a-bep20-contract-for-small-fee/26530 "2026-08-02T19:04:21Z")
I need BEP20 contract code that I can deploy and learn, I maybe need need tax function (marketing wallet and charity wallet), Mintable, Burnable, Pausable, Ownable, I also need a small guide for how can I change functi… --- ## [Transfer an ERC721 from a contract to a wallet](https://forum.openzeppelin.com/t/transfer-an-erc721-from-a-contract-to-a-wallet/36813)
**Author:** [@andreavendrame](https://forum.openzeppelin.com/u/andreavendrame)\ **Replies:** 30\ **Last updated:** [July 30, 2026, 1:21pm UTC](https://forum.openzeppelin.com/t/transfer-an-erc721-from-a-contract-to-a-wallet/36813 "2026-07-30T13:21:37Z")
Good morning. In order to create a sort of renting service I need to a mirrored version of an ERC721 contract. The mirrored version is the token that will be transferred to the borrower wallet after the accepting the l… --- ## [Ethernaut - problem with player and ethernaut are not defined](https://forum.openzeppelin.com/t/ethernaut-problem-with-player-and-ethernaut-are-not-defined/3347)
**Author:** [@Jacob\_Walters](https://forum.openzeppelin.com/u/Jacob_Walters)\ **Replies:** 2\ **Last updated:** [July 9, 2026, 12:48pm UTC](https://forum.openzeppelin.com/t/ethernaut-problem-with-player-and-ethernaut-are-not-defined/3347 "2026-07-09T12:48:28Z")
Hi, I am playing ethernaut and am experiencing a problem. When I type player or ethernaut, those keys are undefined. I am using metamask, connected to the ropsten network, my account has 6 ether, I have tried using the c… --- ## [Is Reporting Through security@openzeppelin.org the Correct Process?](https://forum.openzeppelin.com/t/is-reporting-through-security-openzeppelin-org-the-correct-process/45434)
**Author:** [@canhnguyen26](https://forum.openzeppelin.com/u/canhnguyen26)\ **Replies:** 0\ **Last updated:** [July 7, 2026, 1:12pm UTC](https://forum.openzeppelin.com/t/is-reporting-through-security-openzeppelin-org-the-correct-process/45434 "2026-07-07T13:12:12Z")
Hi everyone, I'm new to smart contract security research. Recently I reported what I believe is a potential vulnerability to the OpenZeppelin security team via their security email (@openzeppelin.org/security@openzeppe… --- ## [My Coding Journey: From Finance to Smart Contract Auditor](https://forum.openzeppelin.com/t/my-coding-journey-from-finance-to-smart-contract-auditor/39251)
**Author:** [@JarrodP](https://forum.openzeppelin.com/u/JarrodP)\ **Replies:** 230\ **Last updated:** [July 3, 2026, 2:37am UTC](https://forum.openzeppelin.com/t/my-coding-journey-from-finance-to-smart-contract-auditor/39251 "2026-07-03T02:37:21Z")
I've been really inspired by some of the journeys some users have posted (in particular JulianPerassi and Jshanks21) and the overwhelming support this community offers is something I want to be involved in. Re-iterating … --- ## [Sending and receiving digital currencies](https://forum.openzeppelin.com/t/sending-and-receiving-digital-currencies/45416)
**Author:** [@Nivo\_Nivo](https://forum.openzeppelin.com/u/Nivo_Nivo)\ **Replies:** 1\ **Last updated:** [June 29, 2026, 6:02pm UTC](https://forum.openzeppelin.com/t/sending-and-receiving-digital-currencies/45416 "2026-06-29T18:02:34Z")
Hello everyone I have a puzzling question. Someone requested a USDT receiving address, and I sent it to them. When they sent it, I checked the contract and found that it was a separate, different contract on the USDT. Th… --- ## [OZ Smart Account Builder on Stellar](https://forum.openzeppelin.com/t/oz-smart-account-builder-on-stellar/45403)
**Author:** [@PoulavBhowmick03](https://forum.openzeppelin.com/u/PoulavBhowmick03)\ **Replies:** 0\ **Last updated:** [June 26, 2026, 5:36am UTC](https://forum.openzeppelin.com/t/oz-smart-account-builder-on-stellar/45403 "2026-06-26T05:36:31Z")
Hello. My team and I are building a policy builder on top of OZ Smart Accounts on Stellar, and while researching we hit a couple of things I wanted to check with you. We were looking at whether spending\_limit could cons… --- ## [How can we fix phantom ban issue](https://forum.openzeppelin.com/t/how-can-we-fix-phantom-ban-issue/45347)
**Author:** [@cented](https://forum.openzeppelin.com/u/cented)\ **Replies:** 1\ **Last updated:** [June 21, 2026, 9:13pm UTC](https://forum.openzeppelin.com/t/how-can-we-fix-phantom-ban-issue/45347 "2026-06-21T21:13:12Z")
my question is regarding how can we remove ban of our token on phantom wallet , by verifiying it on explorer or any other solution? kinda urgent please let me know --- ## [Usdt.z contract 21f Token](https://forum.openzeppelin.com/t/usdt-z-contract-21f-token/45381)
**Author:** [@Erick01](https://forum.openzeppelin.com/u/Erick01)\ **Replies:** 2\ **Last updated:** [September 5, 2026, 12:09pm UTC](https://forum.openzeppelin.com/t/usdt-z-contract-21f-token/45381 "2026-09-05T12:09:16Z")
I need help with contract 0xf15c7f1F86398520b70505e9cC285A8b18D9A21f, I need to acquire it but the token owner is withdrawing it from me. --- ## [Deploy a simple ERC20 token in Remix](https://forum.openzeppelin.com/t/deploy-a-simple-erc20-token-in-remix/1203)
**Author:** [@abcoathup](https://forum.openzeppelin.com/u/abcoathup)\ **Replies:** 22\ **Last updated:** [June 20, 2026, 5:03pm UTC](https://forum.openzeppelin.com/t/deploy-a-simple-erc20-token-in-remix/1203 "2026-06-20T17:03:01Z")
I have been using Remix for really quick contracts rather than spinning up a Truffle or a Hardhat project (both of which are still pretty quick to do). Remix supports importing via GitHub. See the documentation for det… --- ## [I've met that bug in website, where should I tell about it?](https://forum.openzeppelin.com/t/ive-met-that-bug-in-website-where-should-i-tell-about-it/45344)
**Author:** [@kuzminkdk](https://forum.openzeppelin.com/u/kuzminkdk)\ **Replies:** 1\ **Last updated:** [May 21, 2026, 9:05pm UTC](https://forum.openzeppelin.com/t/ive-met-that-bug-in-website-where-should-i-tell-about-it/45344 "2026-05-21T21:05:04Z")
Header in website is turned from it's appropriate place, where I scroll down. I've fixed it by turning off that “!important” rule. Where should I tell about that bug? --- ## [I accidentally sent my LP Tokens to Contract Address](https://forum.openzeppelin.com/t/i-accidentally-sent-my-lp-tokens-to-contract-address/45342)
**Author:** [@quack\_ductor](https://forum.openzeppelin.com/u/quack_ductor)\ **Replies:** 0\ **Last updated:** [May 20, 2026, 8:52am UTC](https://forum.openzeppelin.com/t/i-accidentally-sent-my-lp-tokens-to-contract-address/45342 "2026-05-20T08:52:06Z")
Hello guys. I accidentally sent my Liquidity Pool tokens to my contract address (which is supposed to be on dead wallet to burn my LP). Now that liquidity pool tokens is now in my contract address. Is there a way to rec… --- ## [Issue with Level 0 of The Ethernaut](https://forum.openzeppelin.com/t/issue-with-level-0-of-the-ethernaut/45310)
**Author:** [@sileNot](https://forum.openzeppelin.com/u/sileNot)\ **Replies:** 0\ **Last updated:** [April 16, 2026, 12:28pm UTC](https://forum.openzeppelin.com/t/issue-with-level-0-of-the-ethernaut/45310 "2026-04-16T12:28:49Z")
Maybe I'm a fool, but isn't the password the number sequence in the name of the method "method7123949"?. Srry for the dumb question at the level 0 :sob:. --- ## [UUPS Upgrade Successful (event emitted) but Implementation Address Not Updating (BSC Mainnet, Hardhat)](https://forum.openzeppelin.com/t/uups-upgrade-successful-event-emitted-but-implementation-address-not-updating-bsc-mainnet-hardhat/45284)
**Author:** [@awwy](https://forum.openzeppelin.com/u/awwy)\ **Replies:** 3\ **Last updated:** [April 9, 2026, 3:23pm UTC](https://forum.openzeppelin.com/t/uups-upgrade-successful-event-emitted-but-implementation-address-not-updating-bsc-mainnet-hardhat/45284 "2026-04-09T15:23:20Z")
Hi everyone, I’m encountering an issue with my upgradeable contract on BSC mainnet using Hardhat and would appreciate any insights. Context Pattern: UUPS upgradeable contract Network: BSC Mainnet Tooling: Hardh… --- ## [Draft ERC: PhaseGuard — lifecycle state machine for contracts](https://forum.openzeppelin.com/t/draft-erc-phaseguard-lifecycle-state-machine-for-contracts/45273)
**Author:** [@athcb](https://forum.openzeppelin.com/u/athcb)\ **Replies:** 0\ **Last updated:** [March 19, 2026, 8:37am UTC](https://forum.openzeppelin.com/t/draft-erc-phaseguard-lifecycle-state-machine-for-contracts/45273 "2026-03-19T08:37:12Z")
I’m looking for feedback on a draft ERC for PhaseGuard, a fixed lifecycle state machine for smart contracts. The goal with PhaseGuard is to make a class of contract lifecycle vulnerabilities structurally impossible usin… --- ## [\[Defender Sunset\] No migration path for CREATE2 deterministic deployments via hardhat-upgrades](https://forum.openzeppelin.com/t/defender-sunset-no-migration-path-for-create2-deterministic-deployments-via-hardhat-upgrades/45272)
**Author:** [@Santiago\_Hoyos](https://forum.openzeppelin.com/u/Santiago_Hoyos)\ **Replies:** 0\ **Last updated:** [March 18, 2026, 9:47pm UTC](https://forum.openzeppelin.com/t/defender-sunset-no-migration-path-for-create2-deterministic-deployments-via-hardhat-upgrades/45272 "2026-03-18T21:47:24Z")
\[Defender Sunset\] No migration path for CREATE2 deterministic deployments via hardhat-upgrades Summary Defender sunsets July 1, 2026. The official migration guide covers only Monitor and Relayer there is no migration gui… --- ## [Smart contract activation](https://forum.openzeppelin.com/t/smart-contract-activation/45252)
**Author:** [@Tuco\_Indio](https://forum.openzeppelin.com/u/Tuco_Indio)\ **Replies:** 1\ **Last updated:** [March 6, 2026, 3:43pm UTC](https://forum.openzeppelin.com/t/smart-contract-activation/45252 "2026-03-06T15:43:10Z")
Hi! I think I was scammed by my broker. I have an amount of USDT in my wallet but it proved to be fake. He said it is not fake but the smart contract need to be activated. I am pretty sure he is lying. --- ## [Initial alpha release of Hardhat Upgrades plugin for Hardhat v3](https://forum.openzeppelin.com/t/initial-alpha-release-of-hardhat-upgrades-plugin-for-hardhat-v3/45248)
**Author:** [@ericglau](https://forum.openzeppelin.com/u/ericglau)\ **Replies:** 0\ **Last updated:** [March 2, 2026, 10:50pm UTC](https://forum.openzeppelin.com/t/initial-alpha-release-of-hardhat-upgrades-plugin-for-hardhat-v3/45248 "2026-03-02T22:50:27Z")
Hi everyone, we've published an initial alpha version of the Hardhat Upgrades plugin with Hardhat 3 support: @openzeppelin/hardhat-upgrades@4.0.0-alpha.0 This release includes: Hardhat 3 compatibility updates Usage do… --- ## [Need help in locking a PCS LP](https://forum.openzeppelin.com/t/need-help-in-locking-a-pcs-lp/45232)
**Author:** [@jose\_antonio](https://forum.openzeppelin.com/u/jose_antonio)\ **Replies:** 0\ **Last updated:** [February 22, 2026, 4:32am UTC](https://forum.openzeppelin.com/t/need-help-in-locking-a-pcs-lp/45232 "2026-02-22T04:32:08Z")
Hi all, i am trying to lock a PanCakeSwap LP to reference a pricing oracle to fix spot prices against my token. tried via code, no go. Here’s the link for the LP need help befoore adding more LP :1234: Code to re… --- ## [Ethernaut Community Solutions](https://forum.openzeppelin.com/t/ethernaut-community-solutions/561)
**Author:** [@martriay](https://forum.openzeppelin.com/u/martriay)\ **Replies:** 8\ **Last updated:** [February 20, 2026, 10:01am UTC](https://forum.openzeppelin.com/t/ethernaut-community-solutions/561 "2026-02-20T10:01:14Z")
Continuing the discussion from Ethernaut category, where @scammi compiled many solutions: Video walk-through: Status - Smart Contract Vulnerabilities: Ethernuats Tim Holmes Mitra - Ethernaut Challenges playlist David … --- ## [InvariantGuard : A framework to make DELEGATECALL safer](https://forum.openzeppelin.com/t/invariantguard-a-framework-to-make-delegatecall-safer/45206)
**Author:** [@Helkomine](https://forum.openzeppelin.com/u/Helkomine)\ **Replies:** 0\ **Last updated:** [February 11, 2026, 7:26am UTC](https://forum.openzeppelin.com/t/invariantguard-a-framework-to-make-delegatecall-safer/45206 "2026-02-11T07:26:58Z")
Proposed new library for OpenZeppelin: InvariantGuard Background DELEGATECALL was introduced very early in Ethereum (EIP-7) as a safer successor to CALLCODE. It is a particularly powerful opcode: it allows a contract … --- ## [Review Request: AOXC Upgradeable Token with Inflation Control & Daily Limits](https://forum.openzeppelin.com/t/review-request-aoxc-upgradeable-token-with-inflation-control-daily-limits/45189)
**Author:** [@orcun](https://forum.openzeppelin.com/u/orcun)\ **Replies:** 0\ **Last updated:** [February 2, 2026, 9:47pm UTC](https://forum.openzeppelin.com/t/review-request-aoxc-upgradeable-token-with-inflation-control-daily-limits/45189 "2026-02-02T21:47:14Z")
\`\`\`solidity // SPDX-License-Identifier: MIT pragma solidity ^0.8.33; import {Initializable} from "@openzeppelin/contracts-upgradeable/proxy/utils/Initializable.sol"; import {UUPSUpgradeable} from "@openzeppelin/contr… --- ## [Compatibility/Support of old manifest formats](https://forum.openzeppelin.com/t/compatibility-support-of-old-manifest-formats/45117)
**Author:** [@Eduardo\_Vasques](https://forum.openzeppelin.com/u/Eduardo_Vasques)\ **Replies:** 2\ **Last updated:** [January 29, 2026, 10:28am UTC](https://forum.openzeppelin.com/t/compatibility-support-of-old-manifest-formats/45117 "2026-01-29T10:28:29Z")
I am trying to run upgrade on smart-contracts that were deployed still using the ProxyAdmin \<=v4 implementation. I still have my manifest file, from several years ago. I detect that there's a change on the information in… --- ## [Sharing Experiences with Immunefi Bug Bounties](https://forum.openzeppelin.com/t/sharing-experiences-with-immunefi-bug-bounties/45165)
**Author:** [@6th\_Sense](https://forum.openzeppelin.com/u/6th_Sense)\ **Replies:** 0\ **Last updated:** [January 22, 2026, 12:36pm UTC](https://forum.openzeppelin.com/t/sharing-experiences-with-immunefi-bug-bounties/45165 "2026-01-22T12:36:22Z")
Seeing how fast hackers can drain crypto is scary. Platforms like Immunefi promise to help, but does it really work? Immunefi helps protect blockchain projects like DeFi apps, wallets, and networks by finding bugs before… --- ## [Introduce yourself here!](https://forum.openzeppelin.com/t/introduce-yourself-here/88)
**Author:** [@martriay](https://forum.openzeppelin.com/u/martriay)\ **Replies:** 453\ **Last updated:** [January 22, 2026, 11:49am UTC](https://forum.openzeppelin.com/t/introduce-yourself-here/88 "2026-01-22T11:49:14Z")
Welcome to the OpenZeppelin Community forum :tada: This thread is for you to say hello to everyone in the community and tell more about you :slight\_smile: If you’re not sure how, try with some of these: Why are you h… [Next page](https://forum.openzeppelin.com/latest.md?page=1)