Блокчейн и Python

Александр Горелик (VP Product @ VChain) на Moscow Python Conf 2017
"Веду разработку на блокчейне уже 2 года - начинал как энтузиаст, но теперь, в рамках собственного проекта, это является моей основной деятельностью. В рамках доклада я расскажу про проблемы, которые помогает решать блокчейн, как эти проблемы решали раньше и почему с блокчейном - лучше. Обсудим когда это всего лишь инструмент, а когда - нечто большее. Рассмотрим области применения, а также когда и как его стоит использовать и для решения каких задач. Поделюсь подходами к выбору блокчейна для решения нужной задачи. Расскажу что есть в Python для работы с блокчейном, а чего - нет. Задачей доклада вижу дать интересующимся разработчикам, которые только слышали про блокчейн, или знают лишь общие концепции, хорошую стартовую площадку для дальнейшего самостоятельного изучения в глубину".\
Видео: https://conf.python.ru/blockchain-python/

Transcript

1. Blockchain & Python
   

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2. I’m not a Crypto-anarchist
   

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3. I’m not a Crypto-anarchist
   Will try to make an objective view
   

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4. I. Expectations
   and takeaways
   What’s this lecture about?
   

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5. This lecture is NOT about
   HOW Blockchain works
   

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6. It’s not about deep
   protocol understanding either
   Segregated Witness
   SegWit2x
   HD Wallets
   zkSNARKs Lightning
   Side chains
   BIPs Soft fork
   Hard fork UASF
   UAHF
   Multisig
   Casper
   Proof of Stake
   Blocksize
   Hash-Time Lock Contracts
   UTXO
   Consensus
   Oracle
   Merkle Trees
   ECC
   

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7. Mining is out of scope as well
   

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8. How can a developer USE Blockchain
   Except to become a millionaire through ICO
   

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9. A desired takeaway
   Overview + good starting point for further self-study
   

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10. II. What is the current
    state of art?
    What should a developer know?
    

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11. Blockchain space is a total mess
    

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12. Similar to the early days of HTTP
    

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13. BUT still is very immature
    

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14. Frameworks, approaches and tools are arising
    Best practices are evolving
    

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15. BTC/ETH stalls - what to do?
    You should be prepared
    

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16. Confirmations
    Always remember about orphan blocks
    

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17. Crypto will punish you. HARD
    Tiny mistakes - HUGE consequences
    

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18. Who is in control of YOUR Blockchain?
    

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19. Could be NOT YOU tomorrow
    Who is in control of YOUR Blockchain?
    Segwit2x
    

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20. Decentralisation comes with a price
    Full node should be nearby
    140GB
    and growing…
    

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21. OR rely on 3rd parties
    But be aware of Cybil attack
    ?
    

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22. But own full nodes are MUCH more secure
    Spread the risk!
    

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23. Legality is still a question
    Anything could happen, really
    

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24. III. When does it make
    sense to use it?
    And when it doesn’t
    

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25. Everything is better with Blockchain
    

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26. Blockchain CAN’T help/solve everything
    Nope, it is not
    

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27. It’s not an efficient database
    Not even near
    

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28. Neither it is a Global Computer
    #sorrynotsorry, Vitalik!
    

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29. Obvious use case
    

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30. Obvious use case
    Full node + RPC
    

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31. Obvious use case
    Full node + RPC 3rd parties APIs
    

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32. Micro payments
    Low TX costs, less friction & clearance
    

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33. Payments, money & asset transfer
    Where there is NO bank accounts
    

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34. Timestamping / record keeping
    Keep data off the ledger, hash to OP_RETURN
    

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35. Decentralisation + !Consensus!
    Removing trust, trusted authorities and intermediaries
    

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36. Privacy
    Voting, Identity, GDPR
    

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37. When it is more than just a tool
    Entirely new use cases, new Blockchain infrastructure
    Lightning Network
    

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38. IV. How do we choose
    the right Blockchain?
    Major factors
    

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39. Consensus mechanism
    Proof of Work
    Proof of Stake
    PBFT (Hyperledger)
    BFT (Tendermint)
    FBA (Stellar)
    Paxos / Raft
    Really a HUGE topic to discuss and research
    

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40. Block times
    Remember, we are talking SECONDS here
    

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41. Cost per TX
    And its trend
    

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42. Capabilities
    Timestamping, asset issuance, smart contracts, privacy, …
    

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43. Write your own from scratch?
    Really BAD idea
    

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44. Use what is there already
    Hyperledger
    Monax
    Credits
    Multichain
    Tendermint
    If you REALLY need to
    Ethereum
    Exonum
    CoCo
    

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45. V. What do we have in Python?
    

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46. Customer facing DApp?
    Forget about Python
    

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47. ecdsa
    pybitcointools
    pycoin + pycoinnet
    21.co
    Bitcoin Ethereum
    pyethereum
    Populus
    Web3.py
    python-bitcoinlib
    pycoind
    Bitcoin Armory
    btcpy
    Eth-TestRPC
    ethereum-utils
    ethereum-abi-tools
    py-evm
    py-solc
    

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48. THANK YOU!
    Aleksandr Gorelik
    CTO @ VChain
    alex@vchain.tech
    

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