Ganache
Personal blockchain for Ethereum development
...Quickly see the current status of all accounts, including their addresses, private keys, transactions and balances. See the log output of Ganache’s internal blockchain, including responses and other vital debugging information. Configure advanced mining with a single click, setting block times to best suit your development needs. Examine all blocks and transactions to gain insight about what’s happening under the hood. Byzantium comes standard, giving you the latest Ethereum features needed for modern app development. Each platform has an associated npm run configuration to help you build on each platform more easily. ...