The reality of Blockchain programming

#ethereum #blockchain talk I gave at https://polyconf.com

Demo video
https://www.youtube.com/watch?v=yfm1NKsA4j0

References

https://ethereum.org/token
https://ethereum.github.io/browser-solidity
https://github.com/ethereum/yellowpaper
http://truffleframework.com
https://github.com/ethereum/wiki/wiki/Safety
https://github.com/OpenZeppelin/zeppelin-solidity
https://etherscan.io
http://ethgasstation.info
https://github.com/ethereumjs/testrpc

Transcript

1. @makoto_inoue @makoto The reality of Blockchain programming
2. WT* is blockchain?
3. Distributed Ledger (DLT) Blockchain = Distributed Database that keeps track of value Blockchain Crypto
4. Ethereum = Blockchain + SmartContract
5. “Hello World” of Smart Contract
6. ICO (Initial Coin Offering)
7. Got it, who are you BTW?
8. London Ethereum “CodeUp”
9. - Limited space - Huge sign ups - No turn ups Meetups - 50% problem Expectation Reality
10. - Escrow model - Micro payment - Game theory Solution - Block Party!!
11. Demo: https://www.youtube.com/watch?v=yfm1NKsA4j0
12. TOC - 1. Learn Blockchain programming in 3 steps - 2. Everything you got is essentially a bounty - 3. Performance tuning for fun and profit
13. 1. Learn Blockchain programming in 3 steps
14. Smart Contract language: Solidity
15. Hop: msg.sender
16. Step: msg.value
17. Jump!: address.send()
18. 2. Everything you’ve got is essentially a bounty Emin Gün Sirer
19. May 2016
20. HACKED!!!
21. Smart contract programming requires a different engineering mindset ... similar to hardware programming or financial services programming than web or mobile development. https://github.com/ethereum/wiki/wiki/Safety
22. Is my code okay?
23. Of course, not
24. payback()
25. Send money
26. To all participants...
27. Including to a code
28. The fix
29. It’s Party time!
30. Sep 2016
31. 100%!!!
32. Feb 2017
33. 2 no turn ups 70%
34. 3. Performance tuning for fun and profit
35. Blockchain = Distributed Database that keeps track of value
36. Transaction fee = Gas https://www.upload.ee/image/5710187/Screen_Shot_2016-04-07_at_10.20.25.png
37. The total transactions cost
38. Ether = 10^18 Wei 1: wei 10^9: gwei 10^12: szabo 10^15: finney 10^18: ether
39. June 2017
40. The rise of Ethereum $400 $10 $13
41. CodeUp #21
42. £££££
43. How Ethereum charges you
44. Gas limit > gas * gasPrice
45. Gas Limit Gas Limit > gas * gas price
46. Gas Price Gas Limit > gas * gas price
47. Gas Price Gas Limit < gas * gas price 20G -> 2G $5 -> $0.5
48. Writing performance test in JavaScript
49. Transaction Hash
50. getTransaction / getTransactionReceipt
51. gasUsed * gasPrice
52. Testrpc (in Memory)
53. gasPrice = 100 gwei
54. 20Gwei
55. gasPrice = 20gwei
57. Gas time Calculator 232 sec 2 Gwei
58. gasPrice = 2gwei
59. Deployed after 300 blocks (= 75 min)
60. I am ready
62. 22nd June 2017
63. Does anyone still remember this?
64. FORGOTTEN !!!
65. http://www.coindesk.com/ico-investments-pass-vc-funding-in-blockchain-market-first/
66. Status.im ICO
67. Status.im ICO
68. 60Gwei
71. Future Of BlockParty
72. Apr 2017
73. > 200 people
74. 200 people
75. GasLimit 4m
76. > 2000 people
77. 2000 people
78. Error: VM Exception: out of gas...
79. Solution
80. Refactoring with £3.47 saving
81. Interested in Ethereum ?
82. The good news $400 $10 $13 $240
83. https://ethereumfoundation.org/devcon3
84. https://www.meetup.com/Ethereum-Paris http://www.asseth.fr
85. http://breaktheblock.simplybusiness.co.uk
86. @makoto_inoue @makoto Thanks DISCLAIMER: THE CONTENT ON THIS SLIDE IS PROVIDED AS GENERAL INFORMATION ONLY AND SHOULD NOT BE TAKEN AS INVESTMENT ADVICE
88. Is my Dapp Okay now?
89. Not sure
90. https://github.com/OpenZeppelin/zeppelin-solidity
91. Bug Bounty as a smart contract
92. Bounty smart contract
93. Bounty smart contract
94. Bounty smart contract
95. 0x13a86ba15dacbd43f037718b243eb67e1bc9acad 1 ETH ($248)
96. @makoto_inoue @makoto Thanks DISCLAIMER: THE CONTENT ON THIS SLIDE IS PROVIDED AS GENERAL INFORMATION ONLY AND SHOULD NOT BE TAKEN AS INVESTMENT ADVICE
97. Resources https://ethereum.org/token https://ethereum.github.io/browser-solidity https://github.com/ethereum/yellowpaper http://truffleframework.com https://github.com/ethereum/wiki/wiki/Safety https://github.com/OpenZeppelin/zeppelin-solidity https://etherscan.io http://ethgasstation.info https://github.com/ethereumjs/testrpc