Simple-To-Install Solidity Flattener v1.0.1 Released

A Simple-To-Install Solidity Flattener

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OAX Swim Gateway Stable Coin Contract Audit

OAX Swim Gateway Stable Coin Contract Audit

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Ethereum Alarm Clock Smart Contract Audit

Ethereum Alarm Clock Smart Contract Audit

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Svandis Crowdsale Contract Audit

Svandis Crowdsale Contract Audit

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MakerDAO Sai (Dai) Stablecoin Contract Audit

MakerDAO Sai Contract Audit

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BokkyPooBah’s Gas-Efficient Solidity DateTime Library v1.00 Released

GitHub BokkyPooBah’s Solidity Gas-Efficient DateTime Library.

Medium article BokkyPooBah’s Gas-Efficient Solidity DateTime Library.

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Blue Frontiers Varyon Contract Audit

Blue Frontiers Varyon Contract Audit

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OneLedger Crowdsale Contract Audit

OneLedger Crowdsale Contract Audit

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Zero Carbon Project / Energis Private PreSale Contract Audit

Energis Private PreSale Contract Audit

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Shipchain Token Contract Audit

The original audit was completed on Feb 24 2018 based on Shipchain’s private repository source code. This audit has now been updated to be based on Shipchain’s public repository source code.

Shipchain Token Contract Audit

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Web3 Design Principles – A framework of UX rules for Blockchain based Distributed Applications (part 1)

Web3 Design Principles – A framework of UX rules for Blockchain based Distributed Applications (part 1)

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Contract Storage and Upgrade in Augur and Colony

Contract Storage and Upgrade in Augur and Colony

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The State of Ethereum Scaling, March 2018

The State of Ethereum Scaling, March 2018

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ScalingNOW! — Scaling Solution Summit Summary

ScalingNOW! — Scaling Solution Summit Summary.

Transcripts can be found at ScalingNOW! Summit Transcript.

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All videos from EthCC ’18 in Paris

All videos from EthCC ’18 in Paris

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Guide To Using The Gnosis Multisig Wallet

Here are a series of screenshots that will give you an idea of the process to use the Gnosis (ConsenSys) Multisig Wallet using a) a Ledger Nano S (Nano) and b) a MetaMask account.

In this guide, I will be using:

  • the Ropsten Testnet Ethereum network
  • the Gnosis Multisig UI at https://wallet.gnosis.pm/, with settings selected to the Ropsten network
  • Ropsten Testnet ethers (RtETH)
  • Ropsten Testnet Dollops tokens (DOLL). Address 0x362fa7d41a47874cf5231dc12ac7ca1339d1090d, 18 decimal places with the symbol DOLL
  • Ledger Nano S (Nano) running in Chromium (not Chrome)
  • Firefox with the MetaMask plugin

 


Table Of Contents

 


1. Ledger Nano S

In this guide, I will be using the following seed phrase with my Nano – license diagram pelican spy monitor convince damage script wall hockey goose month popular swamp sugar rose mystery gap regular acquire bottom sea modify eyebrow. The account generated from this passphrase is 0x98Cf7199F4e0c977196AAfa64c6A240fEBb7b73e. I have sent some RtETH and tokens to this account.

On my Ledger Nano S, I selected the Ethereum icon -> Settings. I then selected Contract Data to yes and Browser Support to yes.

 


2. MetaMask

In this guide, I will be using the following seed phrase with my MetaMask account – devote double van helmet sausage decide eyebrow impact into sick spice banner. The account generated from this passphrase is 0x30996B7848Bf844F0DA4E33E92AC958DC6789CE8. I have sent some RtETH to this account.

 


3. Connecting Wallet User Interface To Ropsten

For this guide, I am setting up a multisig wallet from 2 separate web browser sessions. The first is using Chromium web browser (not Chrome, but that works too) with the Ledger Nano S connected to this session. The second is using the Firefox web browser with the MetaMask plugin.

In both sessions, navigate to https://wallet.gnosis.pm and select the Settings tab.

Nano

In this Nano session, select the Remote Ropsten Ethereum node and Ledger Wallet Web3 provider. Click Update settings. You may have to refresh your web browser page for the settings to become active.

Multisig Nano Setting

 

MetaMask

In this MetaMask session, select Ethereum node Remote Ropsten and Web3 provider Default (MetaMask, Mist, Parity …). Click Update settings. You may have to refresh your web browser page for the settings to become active.

Multisig MetaMask Setting

 


4. Deploying A New Wallet

Let’s deploy a new multisig wallet from the Nano session.

Nano

Click on Add on the right of Wallets:

Multisig Nano – Add Wallet

Enter a name for the wallet, the number of required confirmations, and the addresses of the owners:

Multisig Nano – Deploy New Wallet

Check the gas and Send transaction. Press the confirm button on the Nano:

Multisig Nano – Send Transaction

https://ropsten.etherscan.io/tx/0x81306e001210d956176b904462f7afcc05625f5bfe92f62b75f91bc1aa6dfc97

EtherScan – Multisig Wallet Created

The wallet has been created:

Multisig Nano – Wallet Created

I’ve sent some RtETH and some DOLL tokens to the wallet contract address 0x6cf5aabb3e349ccd363e1e1de8b83ad4b35fb681:

Multisig wallet contract address – sent some RtETH and DOLL tokens

You can see the RtETH balance on the webpage:

Multisig Nano – ETH Balance

Click on the wallet name to view the wallet details:

Multisig Nano – View Wallet

Click on the Add button to the right of Tokens. Enter the address 0x362fa7d41a47874cf5231dc12ac7ca1339d1090d and the other fields are filled in:

Multisig Nano – Add Token

You can now see your token balance in the wallet:

Multisig Nano – View Token Balance

MetaMask

In the MetaMask session, click on Add to the right of wallets:

Multisig MetaMask – Add Wallet

Click on Restore deployed wallet and Next:

Multisig MetaMask – Restore deployed wallet

Enter the name and address of the newly created wallet 0x6cf5aABB3e349Ccd363E1E1DE8b83aD4b35FB681 and click Ok:

Multisig MetaMask – Restore deployed wallet

You will now see the wallet including the RtETH balance in the MetaMask session:

Multisig MetaMask – View ETH Balance

 


5. Executing Multisig ETH Transactions

MetaMask

Let’s withdraw some ETH from the multisig wallet from the MetaMask session.

Click on the Withdraw button to the right of the multisig wallet entry:

Multisig MetaMask – Withdraw ETH

Enter the Amount (ETH), the Destination address and click on Send multisig transaction:

Multisig MetaMask – Configure Gas

Customise the Gas limit and Gas price (GWei) and click on Send transaction:

Multisig MetaMask – Confirm MetaMask Transaction

Click on the Submit button to send the transaction.

https://ropsten.etherscan.io/tx/0x6b5e8b2ed126b06a84e04926229462de18ffd471469da2335cda8c87c01c7652

Ropsten EtherScan – confirmTransaction

Multisig Nano – New Unconfirmed Transaction

Multisig Nano – Confirm Transaction

 

Multisig Nano – Configure Gas

 

Multisig Nano – Transaction Confirmed

Here is transaction https://ropsten.etherscan.io/tx/0xb290452ea4e7cc6093ab8c52f38c57a9338d9f2944a43a5b230b3589153d70e3 .

Ropsten EtherScan – confirmTransaction

 

 

 


6. Executing Multisig ERC20 Token Transactions

Multisig Nano – DOLL Token Balance

 

Multisig Nano – Withdraw DOLL Tokens

https://ropsten.etherscan.io/tx/0x77f0219e711eb318532378bc402e5354b8d90552bb047c85a4ae5081fbade0c3

EtherScan – Submit DOLL Token Transfer Transaction

 

Multisig Nano – Unconfirmed Token Transfer

 

Multisig MetaMask – Unconfirmed Transaction

 

Multisig MetaMask – Confirm Transaction

 

Multisig MetaMask – Token Transfer – Configure Gas

 

MetaMask – Submit Transaction

https://ropsten.etherscan.io/tx/0x507c4eefd4c0414365b7a28cd570881e699840037f54b6548861e7fde7ba34ee

EtherScan – Confirm DOLL Token Transfer Transaction

 

Multisig MetaMask – DOLL Tokens Transferred

 

Multisig Nano – DOLL Tokens Transferred

 


7. References

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Notes From The Web3 Foundation Decentralised Exchange Workshop In Berlin Jan 23 2018

The Web3 Foundation organised a Decentralised Exchange (DEX) workshop in Berlin, inviting most of the major DEXes in the Ethereum space.

Web3 Foundation Decentralized Exchange Workshop : Jan 22 – 24

The Web3 Foundation is organizing the top teams working on decentralized exchanges to facilitate a 1-day workshop. Our goal is to come away with a list of prioritized issues which affect a number of projects. From there, we aim to align resources and find pragmatic solutions to the issues outlined. This could be in the form of bounty or grant programs, funding specific research and development initiatives, etc.


Participants


My Notes

Currently trying to categories the ~13 projects into the different types of DEXes:
1. Order Book - On or Off Chain
2. Provably Fair Matching Y/N
3. Order placement
4. Throughput
5. Latency
6. Cost
7. Privacy
8. Legal
9. Target users
10. Assets
11. Worst case failure
12. Dev stage


0x Protocol
- Off chain order book, on chain protocol
- Use ERC20 allowance of tokens to the 0x contracts (vs EtherDelta where you deposit tokens in the ED wallet)
- Relayers job to watch the orders and prune orders
- Also a cancel, but that can be frontrun
- Like the EtherDelta smart contract, but more an API
- Diff to EtherDelta
** ED has a deposit contract, and have to withdraw
** 0x - user always have the funds in the wallet
- 0x token for governance, fee in 0x
- Radar relay has a head start, most volume going through them
1. Off chain matching, onchain settlement
2. Up to the relayer
3. ?
4. Settlement limited by Ethereum blockchain. Every trade is settled individually, cannot group ATM
5. Blocktime
6. Gas cost + relayers fee
7. None, once settled
8. They have a law firm. 0x is an open source protocol. Relayers have to decide how to comply.
9. Crypto holders + Dapps
10. ERC20. Will be adding EIP721 non-fungible token support
11.
12. Working on V2 currently. 3 relayers on mainnet.



Radar Relay, based on the 0x protocol:
1. Off chain
2. Open orders - no matching
3. Off chain order book, on chain settlement


Gnosis DX
- DEX based on Ethereum. ERC20/ERC20
- Dutch auction exchange for any kind of token pairing
- No cancelled orders
1. On chain
2. Yes
3. No front-running
4. Ethereum, slow
5. Slow
6. Gas + Fees (distributed to the ecosystem), half paid in Gnosis token
7. Everything is onchain
8. Legal - decentralised
9. No high frequency traders
10. ERC20 + wrapped ETH
11. No liquidity
12. Code complete


Airswap
- No price discovery, local auction you have access to
- Order information - price and size
- Request sent to cparty (counterparty), cparty sends back signed message, request sender can then execute
- Network can be spammed
- P2P model, can do reputation system
- Can Wrapped ETH be made part of the ETH protocol? Vlad - Don't want ERC20 ETH on protocol level
1. Peer to peer design
2. N/A
3. Orders passed directly P2P. Trade request communicated directly between peers
4. OK. Limited by Ethereum network
5. OK.
6. Gas
7. Trading P2P (no price discovery). As private as P2P implementation
8. Legal
9. Mid-sized / HFT
10. ERC20 (will move into BTC if they can work out some bonding mechanism, wrapped BTC, BTCRelay works only one direction)
11. People can be ripped off - no price discovery
12. Went on Mainnet last week. 20 people. Private testing.


OmiseGo (OMG)
- Discussion of Plasma, using Merkle trees. Tree of chains, each chain secured by parent
- Multiple children, potential multiple parent anchor points
- Exchange to be built after Plasma developed
- Tendermint is a temporary solution while Plasma is being built
- Tokens emitted by corporate clients (loyalty points) of OMG, not ERC20
1. On chain, later to Plasma
2. (unknown, new area for OMG)
3.
4. Tendermint PoS chain. OMG token used for staking.
5. 1s
5.
6. Will have gas like Ethereum
7. No in Tendermin, Yes in Plasma
8.
9. Corporate clients of OMG, ERC20 holders
10. Corporate tokens
11.
12. Pre-alpha


Augur
- Changed quite a bit in the last 6 months
- Prediction market platform
- Outcome token is swapped for ETH
1. On chain
2. Fair
3. ETH
4. ETH
5. ETH
6. Gas
7. No - ETH
8. Meh
9. Traders, betters, people who want to create markets
10. ETH, outcome tokens
11. Lots, in the reporting system. ETH.
12. In 3rd stage of audits. 2 to 3 weeks of preparation, then live.


DEXY
- State channel, Tendermint
1. & 2. Tendermint
3. Off chain P2P
4. 100 - 1K
5. 1 second
6. Low + taker fees
7. No privacy in the open version, oblivious tx transfer
8. Don't give a fuck. Buy a boat and live on international waters.
9. All users
10. ERC20 + EIP721
11. ETH
12. Pre release
13. Use cases - ?


CryptoDerivatives.Market / GazeCoin / OAX
- CryptoDerivatives.Market - GNT, individual contracts
- OAX - Asset Gateway, collateralised ERC20 tokens
- State Channels next project
GazeCoin details below:
1. On chain
2. Yes
3. ?
4. ETH
5. ETH
6. ETH
7. None
8. Worried
9. VR users
10. ERC20/721
11. ETH
12. Planning
13. Biggest challenge: gas cost


Kyber
- ShapeShift on the blockchain
- B2B platform
1. On chain
2. N/A
3. small issue
4. ETH
5. 1 block
6. Fees, spread, 200k
7. No
8. Complex, Singapore based, accommodate Singapore regulation. Decentralised exchange loosely defined in Singapore law. Security/Utility should not have any consequence. Looking at setting up entities in Belarus. Guidance, not licence. Money changer.
9. B2B, Dapps
10. ERC20
11. Lose gas
12. Mainnet alpha next month


Herdius
- Want to be cheaper than Ethereum
- Sidechain
- 2 private keys generated for wallets
- Threshold signature to trigger movement
1. On chain. People who hold at least 0.2% stake run the chain
2. Yes
3. 45 txs/sec
5. 15 seconds
6. < $1 per trade
7. No
8. Issue going forward (3 or 4 months of legal work before approaching German regulators, then they took 6 weeks of back & forth)
9. Regulated crypto traders
10. All
11. Sidechain goes down. Everything stolen / locked up
12. Prototype
13. Regulation and KYC


Vlad - LLZK - MISC (Matching in a state channel)
1. Order book in State Channel. Matching engine maintains and gossips order book
2. Trusted matching, not provably fair
3. a. Deposit funds into channel; b. Place orders
4. State channel throughput
5. Very low latency
6. State channel cost, 0.15%/0.25% maker/taker fees
7. ZK proof when placing order. Users hold their account state and produce the ZKP on the right to place/cancel orders and withdraw
8. Legal for Vlad to specify
9. ETH
10. ERC20
11. Unfair matching, vanishing/reverting state
12. Not planned
13. Writing


Melonport
- Asset management on the blockchain
- Building Melonchain
- Token contract duplicated on 2nd chain with an additional mint(...) function, like Parity bridge


DEX Issues - Breakout Groups
a. Front Run Prevention [5 people]
- Distributed key generation
- Commit and reveal
b. Ongoing vs Batch [3]
c. Scaling [Loss]
- Polkadot, Cosmos, Plasma, DPoS
d. Legal [9]
- Web3 Foundation may try to set up something where we can share legal advice
e. Privacy [5]
- zkSNARKs (lose ability to know message sender), too much overhead
- Ring signatures (Passive - like Monero, active)
- Set accumulator
f. Liquidity [4]
- No funds
- Legally does not
- Investment risk
- To approach market makers
- Partnership with CEX
- Intradex settlement

For each issue:
- Define
- Map out
- Criteria
- Action item


Legal Breakout Group
- Coala have a working group on ICOs
- Functional equivalences - conversations with regulators
- Web3 Foundation - token sales, KYC and AML
- US - Perkins Coie (Marko)
- Gnosis
** Gibralta - DLT regulation
- Working with regulators, working with law firms
- DLT licence in Gibraltar like BitLicence in NY, but more business friendly
- Gnosis could engage with regulators in Gibralta
- Gnosis - blacklist US from UI
- Airswap is a HK company. Are these securities that are trading on the exchange
- Paradex only listing non-security tokens (US jurisdication)
- Airswap - manual verification of tokens
- Kyber - manual shortlist of tokens
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Sirin Labs Crowdsale Contract Audit

Sirin Labs Crowdsale Contract Audit

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GazeCoin Crowdsale Contract Now Live, With BokkyPooBah’s Token Teleportation Service

GazeCoin Crowdsale Contract

With the first deployment of BokkyPooBah’s Token Teleportation Service Smart Contract

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Devery Presale Contract Completed

Devery Presale Contract Completed

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Gizer Presale Contract Audit

Gizer Presale Contract Audit

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ZeroSum Crowdsale Contract Audit

ZeroSum Crowdsale Contract Audit

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LiveEdu Crowdsale Contract Audit

LiveEdu Crowdsale Contract Audit

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Bluzelle Crowdsale Contract Audit

Bluzelle Crowdsale Contract Audit

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Oracles Network Presale Contract Audit

Oracles Network Presale Contract Audit

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Aigang Crowdsale Contract Audit

Aigang Crowdsale Contract Audit

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Simple Token Crowdsale Contract Audit

Simple Token Crowdsale Contract Audit

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Gizer Crowdsale And Token Contract Audit

Gizer Crowdsale And Token Contract Audit

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Ethereum Devcon3 Conference In Cancun – Unofficial Agenda With Slides, Videos And Links

Status: Work in progress

Agenda: Devcon3 Agenda

Nov 27 2017 – All videos now available – Devcon3 videos available now!

David Lim’s slides extracted from the main hall videos: https://www.etherdevswamp.org/dc3p/

a16z Field Notes: Devcon3 – Ethereum Developer’s Conference – https://a16z.com/2017/11/24/devcon3-notes/

See also:

The materials here are the copyright of their respective creators.


Day 1 – Nov 1 2017

Day 1 Stream Day 1
[embedyt]http://www.youtube.com/watch?v=Yo9o5nDTAAQ&width=600&height=336[/embedyt]

David Burela’s blog – Devcon 3 report: Day 1 – core systems

Topic – Presenter(s) & Resources
Welcome and Opening by Executive DirectorMing Chan
Notes.
{embedyt}


Day 2 – Nov 2 2017

Day 2 Stream Morning Day 2 Morning
[embedyt]http://www.youtube.com/watch?v=8sXzxkODH-c&width=600&height=336[/embedyt]

Day 2 Stream Afternoon Day 2 Afternoon
[embedyt]http://www.youtube.com/watch?v=aMs0wAFIu7I&width=600&height=336[/embedyt]

David Burela’s blog – Devcon 3 report: Day 2

Topic – Presenter(s) & Resources
{topic}{people}
Notes.
{embedyt}


Day 3 – Nov 3 2017

Day 3 Stream Morning Day 3 Morning
[embedyt]http://www.youtube.com/watch?v=k42YNyvG8CU&width=600&height=336[/embedyt]

Day 3 Stream Afternoon Day 3 Afternoon
[embedyt]http://www.youtube.com/watch?v=FPHXbJPVVaA&width=600&height=336[/embedyt]

David Burela’s blog – Devcon 3 report: Day 3 – Dapp development

Time Topic – Presenter(s) & Resources
09:00 {topic}{people}
Notes.
{embedyt}


Day 4 – Nov 4 2017

Day 4 Stream Morning Day 4 Morning
[embedyt]http://www.youtube.com/watch?v=vXVcuWvR5Z0&width=600&height=336[/embedyt]

Day 4 Stream Afternoon Day 4 Afternoon
[embedyt]http://www.youtube.com/watch?v=ugbRyZSPfYE&width=600&height=336[/embedyt]

David Burela’s blog – Devcon 3 report: Day 4 – p2p tech

Time Topic – Presenter(s) & Resources
09:00 {topic}{people}
Notes.
{embedyt}
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RocketPool Presale And Crowdsale Contracts Audit – Crowdsale Audit Completed

RocketPool Presale And Crowdsale Contracts Audit

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