The perils of developing NFT for OpenSea Marketplace

1. “Unidentified contract”

2. Poor Quality on orphaned OpenSea code examples

  • updating dependencies
  • fixing code here and there
  • trying older node versions and newer ones
  • changing operating systems between Intel based Macs and ARM based Macs and even on a blank Ubuntu node

3. The gap between creating a collection on-site on OpenSea and via importing from a contract

4. “There was a problem processing your request”

  1. Use menu item “Transfer”
  2. List an item and someone else wants to buy your item
* Override isApprovedForAll to auto-approve OS's proxy contract
function isApprovedForAll(address _owner, address _operator) public view override returns (bool isOperator) {
// if OpenSea's ERC721 Proxy Address is detected, auto-return true
if (_operator == address(0x58807baD0B376efc12F5AD86aAc70E78ed67deaE)) {
return true;

// otherwise, use the default ERC721.isApprovedForAll()
return ERC721.isApprovedForAll(_owner, _operator);

5. The Multi-Token-Standard without being a Multi-Token-Standard





Ethereum advocate * Full Stack Developer * CTO @ & CTO & Co-Founder @

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Hagen Hübel

Hagen Hübel

Ethereum advocate * Full Stack Developer * CTO @ & CTO & Co-Founder @

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