Ethereum smart contract introduction – HackerDojo

Library overview

The library for interacting with an Ethereum ABI

An example of a smart contract

Information about the contract

Checking the cost of ether to gas

Listing your key

Creating a new wallet

Set your default ether wallet
ethAddressSenderDefaultSet MY_ETH_KEYSTORE

Override your default ether wallet
ethAddressOverride  MY_ETH_KEYSTORE

Importing a contract for crypto kitties
ethContractAbiImport 0x2a03eb37c0077dba0814a004bc53f2567b7587a0

Reading from the blockchain is free.

  • ethTransactionView quip getQuip 0
  • ethTransactionView cryptokitties totalSupply

Writing to the blockchain requires the creation of a transaction. Creating transactions require gas.
ethTransactionInvoke quip addQuip “This is pretty boomz”

Ether has a fluctuating exchange rate for gas. Paying higher gas ensures transaction gets prioritized and mined.

Sending ether to an address
ethTransactionEtherSend MY_ETH_KEYSTORE 0.01 ether

Checking balance in an ether wallet. Balances in all wallets are public
ethAddressBalance  MY_ETH_KEYSTORE

To send money to your local wallet from coinbase simply send the money to that address from your own coinbase account.

Checking the balance of your contract currency (etherscan)

creating a new coin


General practices

  • use Solidity as a programming language
  • always emit an event which generate logs that are free to read
  • Etherscan is subjected to man in the middle attack. Important to encrypt your transactions using TLS


The creator has generally been working on this alone and its a lonely experience. This seems to be common phenomena for creators

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