I had a look at some existing crowdsale contracts:
- https://github.com/aragon/aragon-network-token/blob/master/contracts/AragonTokenSale.sol
- https://github.com/sonm-io/presale-token/blob/master/contracts/PresaleToken.sol
- https://github.com/ConsenSys/Tokens/tree/master/Token_Contracts/contracts
- https://github.com/OpenZeppelin/zeppelin-solidity/tree/master/contracts/crowdsale
- https://github.com/Giveth/minime/blob/master/contracts/MiniMeToken.sol
- https://github.com/TokenMarketNet/ico/tree/master/contracts
- Etheroll: https://etherscan.io/address/0xa9a8108994bb704261567e53b49607a73876ddf1#code
Below is an ASCII graph from Aragon source code. Rather than stages, I'd like to find a contract that implements linear or logarithmic decrease in the amount of tokens...
rollback
function to undo the edit - full URL to github is much more informative than some formatted link. – Mars Robertson Jul 26 '17 at 14:59