Managing a legacy Dapp

Transcript

1. Managing a legacy Dapp @makoto_inoue BlockParty
2. Topics - The legacy Dapp in action
3. Topics - The legacy Dapp in action - Evolution of the code
4. Topics - The legacy Dapp in action - Evolution of the code - Running on mainnet
5. The legacy Dapp in Action
6. - High expectation What is BlockParty? - Solving 50% problem Reality
7. - High expectation - Harsh reality What is BlockParty? - Solving 50% problem https://www.nytimes.com/interactive/2017/01/20/us/politics/trump-inauguration-crowd.html
8. What is BlockParty? - How?
9. “I went to a party and got extra Ether as payout!!”
10. Flow
11. register(“@makoto_inoue”) Admin User
12. attend([“0x123…”, “0x456…”, “0x789…”) Admin
13. payback() Admin
14. withdraw() User
15. Meetups & Parties
16. Meetups & Parties
17. Meetups & Parties
18. Attendance rate
19. Payouts
20. Edcon post conference lunch (19/2/2017)
21. http://noblockno.party (11/3/2018)
22. Evolution of the code
23. The initial commit
24. The initial commit
25. The initial commit
26. The code
27. The code No version number No “payable” keyword No error when missing public
28. The code
29. throw vs return - No error message - Swallow all gas (used to be)
30. throw vs return - Can emit Event - Potentially unsecure?
31. The “Bloody October”
32. The “Bloody October”
33. Byzantine HF
34. throw vs return => require/assert/revert
35. Pull over Push
36. The DAO (30th April - 17th June 2016 )
37. 0xbb9bc244d798123f...
38. The consequence
39. The 7th day
40. Did participants know about this?
41. What should I do with the money?
42. Did I donate?
43. Then what happened?
44. How did that happen?
45. Am I the only fool?
46. Share the best practices!!
47. Share the best practices!!
48. Running on mainnet
49. Gas price, gas price, gas price
50. The power of “default”
51. Gas price, gas price, gas price
52. The power of “default”
53. The power of “default”
54. The power of measuring
55. The power of measuring
56. But be careful...
57. Summary
58. Lessons learnt - Solidity evolves - “The best practices” evolve - You only learn certain stuff on mainnet
59. How do you learn?
60. Move fast And break things http://uslaunchreport.com
61. Move fast And break things http://uslaunchreport.com http://giftrunk.com/gif/trampoline-pool-jump-fail
62. How do you learn (by failing) - Stake small
63. How do you learn (by failing) - Stake small - Know your customer (doesn’t have to be full ID check)
64. How do you learn (by failing) - Stake small - Know your customer (doesn’t have to be full ID check) - Deploy often
65. Thanks! @makoto_inoue http://ethcc.noblockno.party