Blockchain Intro

Transcript

1. Blockchain Introduction. Sota Watanabe January 2019 Staked, Inc.
2. Quick Introduction ౉ล૑ଠ / Sota Watanabe Twitter: @WatanabeSota ৬ྺ • Chronicled • CryptoAge • Staked ࠷ۙ ERC20ͷDEXΛͭ͘Γ·ͨ͠ɻ ৭ʑͳDAppsΛ࡞ͬͯ·͢ɻDeFiΛݟͯ·͢ɻ
3. Quick Introduction ࠓ೔͸஻Γ·ͤΜ͕ɺ๻ͷScrapbox͸ͪ͜Β https://scrapbox.io/StakedTechnologies/
4. Contents 1 2 3 4 5 ϒϩοΫνΣʔϯͷࠜຊࢥ૝ ͍͔ͭ͘ͷ໰͍ جຊతͳ࢓૊Έ ະདྷΛߟ࡯͢Δ ໰୊఺ͱղܾࡦ
5. Contents 1 2 3 4 5 ϒϩοΫνΣʔϯͷࠜຊࢥ૝ ͍͔ͭ͘ͷ໰͍ جຊతͳ࢓૊Έ ະདྷΛߟ࡯͢Δ ໰୊఺ͱղܾࡦ
6. ͍͔ͭ͘ͷ໰͍ ʮDecentralizationʯͬͯͳΜͩΖ͏ʁ ໰ɿ
7. ʮDecentralizationʯͬͯͳΜͩΖ͏ʁ ੈͷதΛDecentralize͢Δʂ Centralized ʮதԝूݖʯ ͜ͷ༁ʹ͋·Γٞ࿦͸ͳ͍͸ͣɻ De-Centralized Decentralization = ඇதԝूݖԽ ?? Distributed de͸઀಄ޠͰʮ཭ΕΔʯ ʮඇʯͱ͍͏ͷ͸൱ఆܗͰ͋ΓdeͰ͸ͳ͍ɻ ࣙॻͰʮDecentralizationʯΛҾ͘ͱ
 ʮ஍ํ෼ݖԽʯ͕ग़ͯ͘Δɻ Decentralization͸ඇதԝूݖԽͰ͸ͳ͍ɻ ͲͪΒ͔ͱ͍͏ͱʮ෼ݖԽʯͱ༁ͨ͠΄͏͕͍͍ɻ Decentralization = Distributed ? Distributed͸ࠨͷ2ͭͱҧͬͯ ݖྗΛද͢୯ޠͰ͸ͳ͍ɻ ͳͷͰʮ෼ࢄԽʯͱߟ͑ΒΕΔɻ ͳͷͰʮ෼ݖԽʯͱʮ෼ࢄԽʯ Ͱ͸ҙຯ߹͍͕ҟͳΔɻ
8. ʮDecentralizationʯͬͯͳΜͩΖ͏ʁ
9. ೔ຊਓ͕DecentralizationΛඇதԝूݖͱ༁͠૝૾͢Δະདྷͱɺ Vitalik͕Decentralizationͱ͍͏ݴ༿Ͱࢥ͍ඳ͘ੈք؍͕ͣΕͯ ͍ΔՄೳੑ͕͋Δͷ͸·͍ͣɻ ʮDecentralizationʯͬͯͳΜͩΖ͏ʁ ALISͰ͜͜Β΁ΜΛهࣄʹ͠·ͨ͠ɻ https://alis.to/Watanabesota/articles/2vAXvpdYXMdp
10. ͍͔ͭ͘ͷ໰͍ ͦ΋ͦ΋ͳͥʮDecentralizationʯ͕େࣄͳͷͩΖ͏͔ʁ ໰ɿ
11. ͦ΋ͦ΋ͳͥʮDecentralizationʯ͕େࣄͳͷͩΖ͏͔ʁ •ϦόλϦΞϯతͳࢥ૝ɺCensorship Resistent ʢ͜͏͍͏ਓ΋͍Δʣ
 •ωοτϫʔΫΨόφϯεʢΦʔϓϯͰಁ໌ͳϝΧχζϜΛ࢖͍ɺ
 ίϛϡχςΟ͕ܾఆ͢Δɻʣ
 •Power to the people.
 •ΞηοτͷΦʔφʔγοϓʢσʔλͳͲʣ
12. •θϩαϜήʔϜ͔ΒϙδςΟϒαϜήʔϜ΁ͷҠߦɻ
 ڝ૪͔Βڞ௨ͷϓϥοτϑΥʔϜͷՁ஋ͷ্ঢΛ໨తͱ͢Δڞ૑΁
 ͳΔͷͰ͸ͳ͍͔ʁ Source: https://medium.com/s/story/why-decentralization-matters-5e3f79f7638e ͦ΋ͦ΋ͳͥʮDecentralizationʯ͕େࣄͳͷͩΖ͏͔ʁ
13. τϥετɺτϥετϨεͱ͸ʁ ໰ɿ ͍͔ͭ͘ͷ໰͍
14. τϥετϨεͱ͸ͳʹ͔ʁ “Blockchain is slow. It’s really complex. It’s lacking a lot of features. But, it has one feature that is never existed before and that’s trust.” Ben Horowitz
15. τϥετϨεͱ͸ͳʹ͔ʁ "Kyber protocol does not hold the users' funds. There is no need for the user to trust us. Users are able to freely verify and audit our smart contracts." Just an example of trust less.
16. τϥετϨεͱ͸ͳʹ͔ʁ ࣾձతඅ༻ͷ1ྫ͸ʮ৴༻ίετʯ
17. τϥετϨεͱ͸ͳʹ͔ʁ ࣮ࡍͷͱ͜ΖɺτϥετϨεͱ͍͏ݴ༿͚ͩͰ͸ෆे෼ͩͱࢥ͏ɻ ਓ΍ػؔʹର͢ΔτϥετΛϓϩτίϧʹҠ৐͍ͯ͠ΔͷͰ͋ͬͯɺ ܾͯ͠τϥετ͕ͳ͘ͳͬͨΘ͚Ͱ͸ͳ͍ɻ τϥετ͢Δର৅͕มΘͬͨɻ
18. ͍͔ͭ͘ͷ໰͍ ݁ہɺύϒϦοΫϒϩοΫνΣʔϯ͕࢖͑Δͷ͸ Ͳ͜ͳΜͩΖ͏ʁ ໰ɿ
19. ύϒϦοΫϒϩοΫνΣʔϯ͕࢖͑Δͱ͜Ζ͸Ͳ͔͜ʁ ࠷ޙʹҰॹʹߟ͑·͠ΐ͏ʂ
20. Contents 1 2 3 4 5 ϒϩοΫνΣʔϯͷࠜຊࢥ૝ ͍͔ͭ͘ͷ໰͍ جຊతͳ࢓૊Έ ະདྷΛߟ࡯͢Δ ໰୊఺ͱղܾࡦ
21. ϒϩοΫνΣʔϯͷࠜຊࢥ૝ Decentralizationͱݴ͏΋ͷͷɺατγɾφΧϞτ͸໌จԽ͍ͯ͠ΔΘ͚Ͱ͸ͳ͍͕ɺ https://www.blockchain.com/explorer Genesis blockʹ͸THE TIMESͷ 04ffff001d0104455468652054696d65732030332f4a616e2f323 030392043 68616e63656c6c6f72206f6e206272696e6b206f66207365636f 6e6420626 1696c6f757420666f722062616e6b73 (σίʔυࡁΈ) EThe Times 03/Jan/2009 Chancellor on brink of second bailout for banks “Chancellor on brink of second bailout for banks” ࡒ຿େਉ2౓໨ͷۜߦٹࡁ͔? ͱ͍͏จࣈ͕ຒΊࠐ·Ε͍ͯΔɻ
22. ϒϩοΫνΣʔϯͷࠜຊࢥ૝ ʮBitcoin: A Peer-to-Peer Electronic Cash Systemʯͷ࿦จ෼ੳ
23. ϒϩοΫνΣʔϯͷࠜຊࢥ૝ Bitcoinͷ࿦จ͸2008೥ɻ
24. ϒϩοΫνΣʔϯͷࠜຊࢥ૝ தԝूݖతͳࠃՈ΍ۜߦʹෆຬ͕͋ͬͨͷͰ͸ͳ͍͔ʁ
 ͱਪଌ͞ΕΔ͜ͱ͕ଟ͍ɻ
25. Contents 1 2 3 4 5 ϒϩοΫνΣʔϯͷࠜຊࢥ૝ ͍͔ͭ͘ͷ໰͍ جຊతͳ࢓૊Έ ະདྷΛߟ࡯͢Δ ໰୊఺ͱղܾࡦ
26. جຊతͳ࢓૊Έ Japan Blockchain AssociationͷʮϒϩοΫνΣʔϯʯͷఆٛ ࢀߟɿJapan Blockchain Association
27. جຊతͳ࢓૊Έ ϒϩοΫνΣʔϯͷಛ௃ ᶃ վ͟Μ͕ۃΊͯࠔ೉Ͱ͋Δɻ ᶄ ࣮࣭0μ΢ϯλΠϜɻ ᶅ 2ॏࢧ෷͍ͷ๷ࢭɻ ͳͥվ͟Μ͕ࠔ೉͔ͱ͍͏ͱ2ͭͷಛ௃͕͋Δɻ 1ͭ໨͸ʮ෼ࢄతʯͳ؅ཧγεςϜ͔ͩΒɻ ͜ͷΑ͏ͳγεςϜΛҰൠతʹP2Pͱ͍͏ɻ(Peer to Peer) ैདྷɺ͓ۚͷऔҾ͸ۜߦͳͲͷୈ3ऀػ͕ؔ஥հ͢Δ͜ͱʹ Αͬͯ৴པੑΛ୲อ͖͕ͯͨ͠ɺ ϒϩοΫνΣʔϯͰ͸શͯͷ ཤྺΛօͰڞ༗͢Δ͜ͱʹΑͬͯ৴པੑΛ୲อ͍ͯ͠Δɻ ͜ΕʹΑͬͯୈ3ऀػ͕ؔඞཁͳ͘ͳΔͱҰൠతʹݴΘΕ͍ͯΔɻ 2ͭ໨͸ʮ֤औҾཤྺ͸ॱ൪ʹϒϩοΫʹऩೲ͞Ε͍֤ͯͯϒϩο Ϋ͕௚લͷϒϩοΫͱͭͳ͕͍ͬͯΔͨΊʹվ͟Μ͕ࠔ೉ʯ ྫ͑͹ɺσʔλ͕อ؅͞Ε͍ͯΔ1ͭͷϒϩοΫͷσʔλΛվ͟Μ ͢ΔͱɺνΣʔϯͰܨ͕͍ͬͯΔલɺޙΖͷσʔλͱͷ੔߹ੑ͕ औΕͳ͘ͳΔͷͰվ͟ΜΛͨ͠Βॠ࣌ʹݟ͔ͭΔɻ ࢀߟɿܦࡁ࢈ۀলࢿྉ
28. جຊతͳ࢓૊Έ ύϒϦοΫ ίϯιʔγΞϜ ϓϥΠϕʔτ ϚΠχϯάϊʔυ ੍ݶͳ͠ ੍ݶՄೳ ੍ݶՄೳ Ӿཡ Φʔϓϯ ੍ݶՄೳ ੍ݶՄೳ ϒϩοΫੜ੒ PoW΍PoSͳͲ೉қ౓ͷ
 ߴ͍࢓૊Έ͕ඞཁɻ ϒϩοΫੜ੒ओମΛݶఆͤ͞Δ ৔߹͕ଟ͍ɻ ೚ҙ ϚΠχϯάใु ඞਢ ೚ҙ ೚ҙ Ϣʔεέʔε Bitcoin, Ethereaum HyperLedger اۀ಺σʔλϕʔε
29. جຊతͳ࢓૊Έ • P2PωοτϫʔΫ • ϋογϡؔ਺ɺిࢠॺ໊ • ίϯηϯαεΞϧΰϦζϜ • εϚʔτίϯτϥΫτ
30. جຊతͳ࢓૊Έ ίϯϐϡʔλʔಉ͕࢜ಉ͡໨తΛ΋ͬͯ઀ଓ͠ωοτϫʔΫΛܗ੒͍ͯ͠Δɻ ϊʔυ͕ಉ͡ॲཧΛ͢Δ͜ͱ͕Ͱ͖ΔͷͰɺ1ͭͷϊʔυ͕ఀࢭͯ͠΋ γεςϜશମʹӨڹΛ༩͑ͳ͍ͷ͕ಛ௃ɻ ࢀߟɿܦࡁ࢈ۀলࢿྉ
31. ʮϒϩοΫʯͱʮνΣʔϯʯͰߏ੒͞Ε͍ͯΔɻ جຊతͳ࢓૊Έʢݩ૆Bitcoinͷ࿩ʣ
32. جຊతͳ࢓૊Έʢݩ૆Bitcoinͷ࿩ʣ • ϒϩοΫͷதʹ͸ҰఆظؒͷτϥϯβΫγϣϯ͕ೖ͍ͬͯΔɻ • ֤ϒϩοΫͷதʹɺલͷϒϩοΫΛϋογϡԽͨ͠ϋογϡ஋͕ೖ͍ͬͯΔɻ • ͜Ε͕͍͍ΘΏΔνΣʔϯͷ໾ׂΛ͍ͯ͠Δɻ • σΟϑΟΧϧςΟʔΛຬͨ͢ϒϩοΫͷϋογϡ஋ΛϚΠφʔ͸ܭࢉͯ͠ࢉग़͍ͯ͠Δɻ
33. جຊతͳ࢓૊Έʢݩ૆Bitcoinͷ࿩ʣ ೖ͍ͬͯΔ஋͸࣮ࡍʹ͸৭ʑ͋Δɻ͜͜Β΁Μ͸Mastering BitcoinΛಡΈ·͠ΐ͏ɻ
34. جຊతͳ࢓૊Έʢݩ૆Bitcoinͷ࿩ʣ Source: Mastering Bitcoin ϒϩοΫϔομʔ͸80byteɺϒϩοΫͷதͰ͸τϥϯβΫγϣϯ͕
 େ͖ͳׂ߹Λॴ༗͍ͯ͠Δɻ
35. جຊతͳ࢓૊Έʢݩ૆Bitcoinͷ࿩ʣ Bitcoin͸UTXOϞσϧɻEthereum͸Stateʢঢ়ଶʣͱ͍͏΋ͷ͕ਪҠ͍ͯ͘͠ɻ
36. جຊతͳ࢓૊Έʢݩ૆Bitcoinͷ࿩ʣ લͷϒϩοΫͷϋογϡ஋͸ϔομʔͷதʹೖ͍ͬͯΔɻ
37. جຊతͳ࢓૊Έʢݩ૆Bitcoinͷ࿩ʣ Merkle Tree ͷ rootͱ͸ͳʹ͔ʁ τϥϯβΫγϣϯͱͱͳΓͷτϥϯβΫγϣϯΛ͋Θͤͨ΋ͷΛϋογϡԽ͢Δɻ TxaͱTXbΛϋογϡԽ͠ɺHaͱHbΛ࡞ΓɺHaͱHbΛϋογϡԽ͢Δ͜ͱʹΑͬͯHabΛ࡞Δɻ Ha͕վ͟Μ͞ΕΔͱ͜ͷ৔߹ɺMerkle rootͷ஋͕มΘΔɻ ͜ͷ࢓૊ʹΑͬͯΦϯνΣʔϯͰొ࿥͠ͳ͚Ε͹͍͚ͳ͍৘ใΛѹॖ͢Δ৔߹ͳͲʹ࢖ΘΕΔɻ
38. جຊతͳ࢓૊Έʢݩ૆Bitcoinͷ࿩ʣ ڞ௨ݬ૝ͷຐྗɻ
39. جຊతͳ࢓૊Έʢݩ૆Bitcoinͷ࿩ʣ ʮνΣʔϯʯͱ͸ͳʹ͔ʁ
40. ҉߸ֶతϋογϡؔ਺ͷಛ௃ •Πϯϓοτͷ௕͞͸Մม͕ͩɺΞ΢τϓοτ͸ݻఆ௕ɻ
 •ରিಥ଱ੑɻΠϯϓοτ͕ҟͳΕ͹Ξ΢τϓοτ΋ҟͳΔɻ
 •Ұํ޲ੑɻΠϯϓοτ͔ΒΞ΢τϓοτ͸ಋ͚Δ͕Ξ΢τϓοτ͔Β
 Πϯϓοτ͸Θ͔Βͳ͍ɻ
 •Πϯϓοτͷେ͖͞ʹ͔͔ΘΒͣΞ΢τϓοτͷ͕࣌ؒҰఆͯ͠଎͍ɻ
41. جຊతͳ࢓૊Έʢݩ૆Bitcoinͷ࿩ʣ • φϯε͸32bitʢ4byteʣɻ • σΟϑΟΧϧςΟʔΛຬͨ͢Α͏ͳφϯεΛݟ͚ͭΔ࡞ۀΛϚΠφʔ͕࣮ߦ͍ͯ͠Δɻ • 10෼ʹ1ݸͷφϯε͕ݟ͔ͭΔΑ͏ʹγεςϜ͕ࣗಈௐ੔͢Δɻ
42. جຊతͳ࢓૊Έʢݩ૆Bitcoinͷ࿩ʣ ϋογϡ஋
43. ిࢠॺ໊ͷϓϩηε ʮൿີ伴ʹΑͬͯ҉߸Խ͞Εͨσʔλ͸ެ։伴ʹΑͬͯݩʹ໭Δɻʯͱ͍͏ੑ࣭ͱ ʮిࢠॺ໊͸ݪຊʹൿີ伴ΛదԠͤͯ͞࡞੒͞Εͨ΋ͷɻʯͱ͍͏ੑ࣭͕ޮ͍ͯ͘Δɻ ֤τϥϯβΫγϣϯʹ1ͭͣͭిࢠॺ໊ͱެ։伴͕͍͍ͭͯΔɻ
44. ެ։伴ͱൿີ伴
45. PoWͷflow
46. PoWͷflow
47. PoWͷflow
48. PoWͷflow
49. PoWͷflow
50. ༷ʑͳίϯηϯαεΞϧΰϦζϜ • PoW • PoS • dPoS • pBFT • PoI • Avalanche • ͳͲͳͲ
51. Contents 1 2 3 4 5 ϒϩοΫνΣʔϯͷࠜຊࢥ૝ ͍͔ͭ͘ͷ໰͍ جຊతͳ࢓૊Έ ະདྷΛߟ࡯͢Δ ໰୊఺ͱղܾࡦ
52. ໰୊఺ •εέʔϥϏϦςΟʔʢ͜ΕଟΊʹ࿩͠·͢ʣ •࣮࣌ؒੑ •ൿಗੑ •Ψόφϯε •ͦͷଞ
53. εέʔϦϯάͷղܾࡦ
54. εέʔϦϯάͷղܾࡦ
55. εέʔϦϯάͷղܾࡦ ॺ໊σʔλͷ࡟ݮ ECDSAͩͱ֤ʑͷॺ໊͕ඞཁͩͬͨɻ ෳ਺ਓͷॺ໊Λ1ͭͷॺ໊ͱͯ͠ ·ͱΊΔ͜ͱ͕Ͱ͖Δ
56. εέʔϦϯάͷղܾࡦ
57. εέʔϦϯάͷղܾࡦ
58. ͦΕͧΕͷϓϥζϚϒϩοΫνΣʔϯͷ࠷ऴతͳঢ়ଶͷΈΛ਌ϒϩοΫνΣʔϯʹه࿥͢Δɻ • ΦϑνΣʔϯॲཧͰ͸ͳ͘ɺPlasmaνΣʔϯͰه࿥͢Δɻ • τϥϯβΫγϣϯͷॲཧੑೳΛ޲্ͤ͞Δɻ
 →εϚʔτίϯτϥΫτͷ࣮ߦΛߴ଎Խ • σʔλαΠζͷݮগ • gasݮগ εέʔϦϯάͷղܾࡦ Plasma!
59. طଘͷ࢓૊Έɿ1000τϥϯβΫγϣϯɺ100ϊʔυˠ1ϊʔυ͋ͨΓ1000τϥϯβΫγϣϯ Shardingɿ1000τϥϯβΫγϣϯɺ100Λ10ͷάϧʔϓʹ෼͚Δˠ1ϊʔυ͋ͨΓ100τϥϯβΫγϣϯ εέʔϦϯάͷղܾࡦ Sharding
60. ͦͷଞʢ͋͑ͯಛචʣ 51%߈ܸͷଟ͘ͷޡղ ଟ͘ͷਓͷࢥ͍ͬͯΔ51%߈ܸ ʮϒϩοΫνΣʔϯ͸վ᜵Ͱ͖ͳ͍͍ͬͯ͏ͷ͸ӕɺ̑̍ˋ߈ܸ͞ΕΔͱͳΜͰ΋ॻ͖׵͑ΒΕͯ͠·͏ʯ ࣮ࡍͷ51%߈ܸ ʮվ͟ΜͰ͖Δͷ͸ࣗ෼Ͱ৳͹ͨ͠ϒϩοΫͷΈɻࣗ෼̍ਓ͕ͨ͠ࢧ෷͍Λͳ͔ͬͨ͜ͱʹͰ͖Δʢ͚ͩʣɻʯ Credit: ೔ஔྰԙಸ @leo_hio
61. ิ଍ ൿಗੑͷ໰୊ʹؔͯ͠͸Zk-SNARKsΛݟΔͱྑ͍ɻZCashͷυ Ωϡϝϯτͱ͔·ͱ·͍ͬͯΔɻ Ψόφϯεʹؔͯ͠͸ɺϓϩτίϧϨΠϠʔͰ͋Ε͹ɺϚΠφʔͷ ࿩͕ɺϛυϧ΢ΣΞҎ্ͷ࿩ͩ͠ͱ MakerDAOɺ0x΍Cryptoeconomicsతͳ࿩͕͠ೖͬͯ͘Δɻ
62. Contents 1 2 3 4 5 ϒϩοΫνΣʔϯͷࠜຊࢥ૝ ͍͔ͭ͘ͷ໰͍ جຊతͳ࢓૊Έ ະདྷΛߟ࡯͢Δ ໰୊఺ͱղܾࡦ
63. ςΫϊϩδʔαΠυ͔ΒΈΔϒϩοΫνΣʔϯۀքͷະདྷʢϚΫϩʣ Web1.0 Web2.0 Web3.0 Source: https://a16z.com/2018/12/16/future-trust-crypto-summit-2018/
65. ςΫϊϩδʔαΠυ͔ΒΈΔϒϩοΫνΣʔϯۀքͷະདྷʢϛΫϩʣ Time 2018 2017 2019 2020 2021 ICO STO ICO͔ΒSTO΁ ICO CEX DEX CEX͔ΒDEX΁ DeFi Stablecoin Stablecoinͷ୆಄ Interoperability PolkadotɼSubstrate ۚ༥DAppsͷຊ֨Խ
66. 2019೥͸DeFi
67. ERC20ͷϦϨΠϠʔΛ࡞ͬͯΈͨ ͔͜͜ΒΞΫηεՄೳ http://app.tokenexchange.jp/home
68. ERC20ͷϦϨΠϠʔΛ࡞ͬͯΈͨ Smart Contract
69. DEX͕ͳͥॏཁͳͷ͔ʁ هࣄΛॻ͖·ͨ͠ɻ https://alis.to/Watanabesota/articles/KJNObpxev6pd
70. ࠷ۙɺҙ͍ࣝͯ͠Δجຊ࢟੎ɺࣗռ΋͜Ίͯ • ൷൑Ͱ͸ͳ͘ɺ୅ସҊΛɻ ϒϩοΫνΣʔϯʹର͢Δ൷൑͸࣮ࡍͷͱ͜Ζ΄΅શͯਖ਼͍͠ɻͦΕ͸͜ͷٕज़͕·ͩൃୡ͍ͯ͠ͳ͍͔ΒͰ͋Δɻ ҆қͳ൷൑Λͯ͠Θ͔ͬͨϑϦΛ͢Δͷ͔ɺ൷൑Λ৐Γӽ͑୅ସҊΛग़͢ͷ͔Ͱ͔ͳΓҧ͏ɻ • ૑Εɻ •ຊ࣭ͱ͸ͳʹ͔ʁ ࣌୅Λ௥͏ͷ͔ɺ࣌୅Λ૑Δͷ͔ɻ৘ใΦλΫʹͳͬͯ΋ੈքʹ௥͍ͭ͘͜ͱ͸Ͱ͖ͳ͍ɻࢥߟ͠ɺઌճΓ͠ ࢓ֻ͚Δ͜ͱ͕େࣄɻ ϒϩοΫνΣʔϯͰ͔͠Ͱ͖ͳ͍͜ͱ͸ͳʹ͔ʁ݁ہ͜ͷ࣭໰ʹճ౴Ͱ͖ΔϓϩμΫτͰ͸ͳ͍ͱੜ͖࢒Βͳ͍ɻ
71. Staked, Inc.