Introduction to writing smart contracts with Solidity and Ethereum.

1. INTRODUCTION TO SMART CONTRACTS
WITH SOLIDITY AND ETHEREUM

2. INTRO
BITCOIN
▸ Cryptocurrency
▸ One shared distributed ledger
▸ Can’t be falsified
▸ Database of transactions
▸ Support for “Script”
▸ Limited smart contracts capabilities

3. INTRO
ETHEREUM
▸ Bitcoin like distributed ledger
▸ Ethereum Virtual Machine
▸ Turing complete
▸ Blockchain
▸ Contracts (code)
▸ Storage
▸ Logs
▸ Events

4. ETHEREUM
HOW IT WORKS?
▸ Every node runs every contract
▸ Deterministic
▸ Ether (cryptocurrency)
▸ Two kind of actors
▸ Contracts
▸ Wallets
▸ Transaction = messages
▸ Code execution spend gas
(ethereum)

5. CONTRACTS
SOLIDITY

6. SOLIDITY

7. SOLIDITY

8. SOLIDITY

9. ETHEREUM.GITHUB.IO/
BROWSER-SOLIDITY

11. ETHEREUM.RB

12. ETHEREUM.RB

14. CONTRACTS
SOLIDITY
▸ Object oriented language
▸ Complied to EVM
▸ Can send and receive ether
▸ Can be run on production, testnet
or private net

15. PURCHASE

16. SOLIDITY

17. SOLIDITY

18. DISTRIBUTED
FUTURE

19. ETHEREUM
LIMITATIONS
▸ Transaction takes coupe of minutes
to be mined
▸ Storage and execution is
expensive
▸ Ecosystem is young

20. ETHEREUM
OFF CHAIN
▸ Half-distributed
▸ IPFS
▸ Oracles and Oraclize
▸ Swarm - distributed storage with
incentives

21. ETHEREUM
METROPOLIS
▸ Casper - proof of stake
▸ Scalability
▸ zkSNARKs - privacy

22. BLOCKCHAIN 2.0?

23. TEXT
USEFUL LINKS
▸ Online editor:
ethereum.github.io/browser-solidity
▸ Blockchain explorer:
testnet.etherscan.io
▸ Ethereum ruby gem:
github.com/marekkirejczyk/ethereum.rb
▸ Example ruby app:
github.com/marekkirejczyk/ruby_ethereum_example

24. THANK YOU!@MAREKKIREJCZYK