const data = [
{ id: 1,
name: 'Fabio Berger + Remco Bloemen',
content: '\n' +
'Fabio\n' +
'Berger + Remco Bloemen
\n' +
'\n' +
'\n' +
'- What type of apps do you\n' +
'build?
\n' +
'
\n' +
'\n' +
'- 0x - Decentralized exchange\n' +
'protocol. It is a set of smart contracts that handle standard\n' +
'transactions in an order format.
\n' +
'
\n' +
'\n' +
'- The key advantage here is that\n' +
'these smart contracts leads to shared liquidity
\n' +
'
\n' +
'\n' +
'- We also achieve increased security\n' +
'and network liquidity through our architecture.
\n' +
'- We launched the network in August\n' +
'2017.
\n' +
'
\n' +
'\n' +
'- It works, but is V1. We are working\n' +
'on V2 which helps people build hybrid stations, supports new token\n' +
'standards, and makes the contract more gas efficient.
\n' +
'- V1 only allows humans to create\n' +
'orders; V2 will allow new smart contract to create orders. This is\n' +
'HUGE.
\n' +
'
\n' +
'\n' +
'- Notes:
\n' +
'
\n' +
'\n' +
'- We’re building the protocol;\n' +
'designing the standard; building dev tools for anyone to build a\n' +
'decentralized exchange.
\n' +
'
\n' +
'\n' +
'- Orders may become invalid for any\n' +
'reason:
\n' +
'
\n' +
'\n' +
'- Order being filled
\n' +
'- Griefing attacks
\n' +
'- We’ve now built an OrderWatcher\n' +
'that keeps relayers updated on the state of orders.
\n' +
'
\n' +
'\n' +
'- We’re using contract Events as a\n' +
'proxy for state changes.
\n' +
'- Can do a diff between state trees\n' +
'and between block headers.
\n' +
'
\n' +
'\n' +
'- We also have a set of smart\n' +
'contracts to handle settlement;
\n' +
'
\n' +
'\n' +
'- Everyone who wants to trade is\n' +
'setting allowances on a smart contract.
\n' +
'
\n' +
'\n' +
'- We want upgradability.
\n' +
'
\n' +
'\n' +
'- What are the\n' +
'tools/libraries/frameworks you use?
\n' +
'
\n' +
'\n' +
'- EthereumJS / truffle hardwallet\n' +
'provider / Typedoc (to generate documentation) /
\n' +
'- We don’t use Truffle\n' +
'anymore
\n' +
'
\n' +
'\n' +
'- Not reliable – can have race\n' +
'conditions;
\n' +
'- Artifacts don’t allow you to have\n' +
'versions of the contract on different networks
\n' +
'
\n' +
'\n' +
'- You don’t run into this stuff if\n' +
'you’re just building a “hello world”
\n' +
'
\n' +
'\n' +
'- Overwriting parts of the\n' +
'contracts;
\n' +
'
\n' +
'\n' +
'- We rolled our own. It’s open-source\n' +
'but not documented. We have other things that are keeping us\n' +
'busy.
\n' +
'- The problem is that Truffle has too\n' +
'much functionality –– we would like to see more of a Unix\n' +
'philosophy.
\n' +
'- Cannot support different versions\n' +
'of Solidity.
\n' +
'
\n' +
'\n' +
'- Version management doesn’t\n' +
'exist.
\n' +
'
\n' +
'\n' +
'- EthPM –– doesn’t have versioning\n' +
'either? It’s going through a big refactor, so we held off. We need\n' +
'the NPM package manager.
\n' +
'- We have built a lot of developer\n' +
'tools to interface with the smart contracts ourselves.
\n' +
'- We have also built own deployer and\n' +
'migration tool, as truffle’s did not suit our needs.
\n' +
'
\n' +
'\n' +
'- What are your biggest\n' +
'frustrations?
\n' +
'
\n' +
'\n' +
'- Getting a simple experimental\n' +
'environment up is hard
\n' +
'
\n' +
'\n' +
'- Remix is there; but it’s not\n' +
'enough.
\n' +
'
\n' +
'\n' +
'- Tracing and profiling is not\n' +
'existent.
\n' +
'
\n' +
'\n' +
'- Remix does it, but can’t do it\n' +
'locally.
\n' +
'- “Code coverage” tool exists but\n' +
'inserts console.logs in
\n' +
'
\n' +
'\n' +
'- Adding up gas costs per line of\n' +
'code.
\n' +
'
\n' +
'\n' +
'- Need to do profiling, because gas\n' +
'costs depend on inputs.
\n' +
'
\n' +
'\n' +
'- Solidity language\n' +
'itself:
\n' +
'
\n' +
'\n' +
'- Crashed the Solidity compiler twice\n' +
'today.
\n' +
'
\n' +
'\n' +
'- E.g. AbiEncoderV2 is pretty new and\n' +
'hard to understand/use.
\n' +
'
\n' +
'\n' +
'- The code that it produces is\n' +
'inefficient.
\n' +
'- There is a stark stack limit in\n' +
'solidity
\n' +
'
\n' +
'\n' +
'- All the variables are locally\n' +
'scoped.
\n' +
'- Un-intuitive as it is a curly\n' +
'braced language.
\n' +
'- The lifecycle hook value_of is\n' +
'within a function.
\n' +
'- Can only access top 16 slack slots.\n' +
'Including input and output.
\n' +
'- We need to implement a graph\n' +
'coloring register allocator – to find out what the lifetime of the\n' +
'variables is.
\n' +
'
\n' +
'\n' +
'- “This stack slot was used in the\n' +
'first half –– the second half you can use”
\n' +
'- Or implement register\n' +
'splitting.
\n' +
'
\n' +
'\n' +
'- Function inlining is frustrating\n' +
'sometimes:
\n' +
'
\n' +
'\n' +
'- E.g. SafeMath –– turns every\n' +
'operator into function call – which is a huge gas sink.
\n' +
'
\n' +
'\n' +
'- How Solidity optimizes could be\n' +
'improved:
\n' +
'
\n' +
'\n' +
'- It focuses on the code size (which\n' +
'makes sense since it’s minimizing the state tree); but sometimes\n' +
'you need to optimize size of tx gas (e.g. 0x needs optimized\n' +
'fillOrder call)
\n' +
'
\n' +
'\n' +
'- ABI doesn’t implement\n' +
'introspection
\n' +
'
\n' +
'\n' +
'- EIP 165
\n' +
'
\n' +
'\n' +
'- E.g. “does this contract implement\n' +
'ERC20, or ERC223?”
\n' +
'
\n' +
'\n' +
'- Solidity should have this\n' +
'in-built.
\n' +
'
\n' +
'\n' +
'- Should be built into the API spec\n' +
'and compiler.
\n' +
'
\n' +
'\n' +
'- Inheritance:
\n' +
'
\n' +
'\n' +
'- Interface or abstract contract –\n' +
'e.g. Solidity automatically creates getters for state functions ––\n' +
'collides with
\n' +
'- Contract which implements an\n' +
'interface – public or external for abstract functions – they\n' +
'collide
\n' +
'
\n' +
'\n' +
'- ERCs – there is not a formal way to\n' +
'describe the interface for contracts.
\n' +
'
\n' +
'\n' +
'- Have a standard repo –– this will\n' +
'lead to a canonical ABI definition –– can have semantic rules\n' +
'around this. Could run some specific unit tests against
\n' +
'
\n' +
'\n' +
'- How do you handle\n' +
'testing?
\n' +
'
\n' +
'\n' +
'- Testrpc has gotten better\n' +
'––
\n' +
'
\n' +
'\n' +
'- Increases the speed at which you\n' +
'can dev.
\n' +
'
\n' +
'\n' +
'- Blockstream is really cool. Written\n' +
'by Mica (from Augur?), under the EthereumJS lib.
\n' +
'- Good dealing with block re-orgs and\n' +
'changes in state.
\n' +
'- Continuous Integration:
\n' +
'
\n' +
'\n' +
'- Doesn’t really work for smart\n' +
'contracts.
\n' +
'- We just use testrpc.
\n' +
'- Neufund was different than\n' +
'0x:
\n' +
'
\n' +
'\n' +
'- Neufund was a trustee for tokens ––\n' +
'it was centralized by definition.
\n' +
'- This made it simpler: I could\n' +
'create “open-ended” contracts –– a switch statement, that the\n' +
'default would send to another proxy contract.
\n' +
'- But wouldn’t be able to do this\n' +
'with 0x –– e.g. if we wanted to add Shnorr signatures –– because\n' +
'it’s a governance / security issues.
\n' +
'
\n' +
'\n' +
'- How do you handle smart contract\n' +
'verification and security?
\n' +
'
\n' +
'\n' +
'- Code audits before\n' +
'deployment
\n' +
'- Want to add a formal verification\n' +
'tool to our deployment tool.
\n' +
'
\n' +
'\n' +
'- By analyzing the code, you can find\n' +
'patterns.
\n' +
'
\n' +
'\n' +
'- I manually did an audit in v0 of\n' +
'0x:
\n' +
'
\n' +
'\n' +
'- Make sure all functions have a\n' +
'“Read -> Write -> External Call” pattern, so you don’t have\n' +
'any race conditions.
\n' +
'
\n' +
'\n' +
'- Other bounties?
\n' +
'
\n' +
'\n' +
'- Rest of the bounties from\n' +
'Remco
\n' +
'- State-watching –– built-in\n' +
'diff’ing of state trees
\n' +
'
\n' +
'\n' +
'- Should be implemented in the\n' +
'Ethereum clients – Geth and Rust.
\n' +
'- They want this feature for\n' +
'OrderWatcher.
\n' +
'
\n' +
'\n' +
'- EIP process is\n' +
'suboptimal:
\n' +
'
\n' +
'\n' +
'- Lacks in consensus-building.\n' +
'There’s vocal people who don’t have good ideas; there’s a lot of\n' +
'noise.
\n' +
'- To improve: committee-based\n' +
'approach (reputable stakeholders from reputable projects who get\n' +
'together?).
\n' +
'- Problems are getting solved at the\n' +
'wrong abstraction level.
\n' +
'
\n' +
'\n' +
'- E.g. NFT standards.
\n' +
'
\n' +
'\n' +
'- Neufund was largest Solidity\n' +
'project before –– tokenized equity.
\n' +
'
\n' +
'\n' +
'- You want a EuroToken. You don’t\n' +
'want your company valuated in Ether.
\n' +
'- What if blockchain forks; which\n' +
'token is actually tied to the company?
\n' +
'
\n' +
'\n' +
'- Bounty approach gives many\n' +
'different styles within the codebase.
\n' +
'
\n' +
'\n' +
'- This is a problem; e.g. OpenSSL\n' +
'codebase after Masters / PhDs.
\n' +
'
\n' +
'',
},
{ id: 2,
name: 'Leo Logvinov',
content: '\n' +
'Leo\n' +
'Logvinov
\n' +
'4/24/2018 - Robbie, Parker,\n' +
'Andy
\n' +
'\n' +
'\n' +
'- Who are you and what are you\n' +
'working on?
\n' +
'
\n' +
'\n' +
'- Started in blockchain 2 years ago\n' +
'in Berlin, working on Ethereum devtools, building solidity plugin\n' +
'for IntelliJ, built by him and an Australian.
\n' +
'- Working on truffle, did some PRs,\n' +
'improving speed, usability, error handling.
\n' +
'- Started working on 0x, primary\n' +
'role: devtools team.
\n' +
'
\n' +
'\n' +
'- What are your biggest\n' +
'frustrations?
\n' +
'
\n' +
'\n' +
'- Event watching - unreliable, no\n' +
'support for backfills etc.
\n' +
'- Build tool for statically typed\n' +
'contract (ABI gen that generates contracts), build out the\n' +
'statically typed libraries
\n' +
'- Negative experience with web3js\n' +
'team - unresponsive.
\n' +
'- Frustrated with truffle because it\n' +
'is hard to contribute with so many packages these days.
\n' +
'
\n' +
'\n' +
'- Hard to debug and understand it all\n' +
'- so needed a smaller truffle for the specific use\n' +
'cases.
\n' +
'- Need to standardise their artifact\n' +
'format (currently in talks about it).
\n' +
'
\n' +
'\n' +
'- Solidity coverage tool: built at\n' +
'hackathon (at least the profiler which is not super useful),\n' +
'standardise on artifacts format so that it works across\n' +
'tools.
\n' +
'
\n' +
'\n' +
'- Which line of solidity is covered\n' +
'by tests?
\n' +
'
\n' +
'\n' +
'- EIP712 - standardised signing for\n' +
'structured data, also helped finalise 721 at ETHDenver.
\n' +
'- Solidity plugin for\n' +
'IntelliJ IDE
\n' +
'
\n' +
'\n' +
'- One did not exist at the time. Did\n' +
'not have too much stuff in it really: simple formatting,\n' +
'definitions, highlighting. Not “a super interesting” project, but\n' +
'has 36 000 users (some duplicates).
\n' +
'
\n' +
'\n' +
'- VMs
\n' +
'
\n' +
'\n' +
'- Been wanting to speed up tests\n' +
'recently. Bottleneck is code execution in Ganache VM (90%). We want\n' +
'to get down to 1-10s test runs.
\n' +
'- GAS PRICES ARE NOT THE SAME!!!!\n' +
'Arghhhhh!
\n' +
'- We need JIT compilation in more\n' +
'performant language (currently just executed in JS).
\n' +
'- Project called EthJIT VM,\n' +
'transpiles to LLL, then optimizes contract so that it is\n' +
'precompiled and then runs much faster.
\n' +
'
\n' +
'\n' +
'- Would be great to see the\n' +
'integrated in ganache (snapshots and time travel make this a nice\n' +
'tool than geth to use currently).
\n' +
'- Even better to have pluggable VMs,\n' +
'have spoken to the Foundation about this too.
\n' +
'
\n' +
'\n' +
'- What tools don’t exist at the\n' +
'moment?
\n' +
'
\n' +
'\n' +
'- Prettier type plugin for\n' +
'solidity. I don’t have time to write it but\n' +
'Prettier has a good API.
\n' +
'
\n' +
'\n' +
'- Other bounties?
\n' +
'
\n' +
'\n' +
'- There is a limit on local variable\n' +
'numbers (have a limit of 16, which influences how you write the\n' +
'code).
\n' +
'
\n' +
'\n' +
'- Solidity doesn’t push variables\n' +
'down the stack, so you can’t go more than 16 deep. This is an\n' +
'implementation detail in current compiler that needs to be\n' +
'improved.
\n' +
'
\n' +
'\n' +
'- ABIv2 - experimental feature for\n' +
'half a year or so - return structures and bus structures as\n' +
'parameters. 0x are planning to use it to make their code easier to\n' +
'audit especially.
\n' +
'
\n' +
'\n' +
'- C++ devs needed
\n' +
'
\n' +
'\n' +
'- Other domain specific\n' +
'questions?
\n' +
'
\n' +
'\n' +
'- What has your experience been\n' +
'like working on EIPS?
\n' +
'
\n' +
'\n' +
'- Working on EIP 712 - signing\n' +
'structured and typed data
\n' +
'- Quite hard with monetary prospects\n' +
'and no established legislation process - need better ways of\n' +
'governing and enforcing the process.
\n' +
'
\n' +
'\n' +
'- Really helped to have everyone in\n' +
'one room at ETHDenver and align on angles of attack.
\n' +
'- Room at ETHDenver from commenting\n' +
'on a thread in GH. Started unstructured and moved into structured\n' +
'discussion by defining the interface, which helped identify all the\n' +
'different parties’ motivations. This revealed some inertia on some\n' +
'teams’ behalf, which was interesting to see.
\n' +
'- Lot of discussions about metadata\n' +
'(of tokens, which is also important for other parts of\n' +
'tokens)
\n' +
'- GH PRs are one single wall of text\n' +
'and the comments need to be better moderated, especially for trolls\n' +
'or tangential discussions/ideas (especially tangential ideas need\n' +
'to be collapsed).
\n' +
'- Creators need to moderate/create a\n' +
'TL;DR section to help people better and more easily grasp what they\n' +
'are working on.
\n' +
'
\n' +
'\n' +
'- Solidity code coverage - how\n' +
'does that work?
\n' +
'
\n' +
'\n' +
'- Before each line calling eval, and\n' +
'modifying Eth and ganache code to read the events, much below the\n' +
'current block gas limit and working through everything that comes\n' +
'through.
\n' +
'- Take debug transaction with list of\n' +
'opcodes. Also have the source maps, which map back from opcodes to\n' +
'lines of solidity code, and can use that the work backwards from\n' +
'opcodes to understand exactly which line used how much\n' +
'gas.
\n' +
'- How do you get the trace after each\n' +
'tx?
\n' +
'
\n' +
'\n' +
'- We wrote our own provider, whenever\n' +
'call to eth_sendTransaction gone through provider it sends it and\n' +
'then gets the trace.
\n' +
'
\n' +
'\n' +
'- Calls don’t have traces though, so\n' +
'need to do a snapshot and then send the call as a tx, which gives\n' +
'you the trace back and then you can look at what happened in the\n' +
'call.
\n' +
'- Did look at other tools, but felt\n' +
'the performance and reliability of those tools just kinda\n' +
'sucked.
\n' +
'
\n' +
'\n' +
'- Can you tell us more about\n' +
'Event Watching?
\n' +
'
\n' +
'\n' +
'- Lacking good open source\n' +
'project[a]
\n' +
'- People don’t have stateful nodes,\n' +
'you need to handle events client side
\n' +
'- Ethereum-js blockstream enables us\n' +
'to use stateless nodes after installing all filters. Still not a\n' +
'part of web3.
\n' +
'
\n' +
'\n' +
'- Working on something called\n' +
'order-watcher: track when the order becomes invalid. Which happens\n' +
'when the user manipulates things. You can validate reactively by\n' +
'watching for events, but you want to actually watch balance changes\n' +
'and events are just an imperfect proxy for this.
\n' +
'- People can mint and burn tokens and\n' +
'change balance without emitting events.
\n' +
'- Want to track changes in balances,\n' +
'not events. balanceOf() is view function that returns the balance,\n' +
'so we want to track the result of calling that.
\n' +
'- Might be inefficient to look at\n' +
'that directly, or we can register callbacks and recompute only when\n' +
'the state used by that function changes.
\n' +
'- But how do we know when state\n' +
'changes?
\n' +
'- Cannot rely on solidity, but can\n' +
'run function, get trace, see which storage slots the function is\n' +
'reading, and then you for sure know that this function will only\n' +
'change its value when one of those storage slots\n' +
'changes.
\n' +
'- Use Patricia tries somehow to watch\n' +
'these storage slots and state changes - allow you to watch\n' +
'efficiently changes on view and pure functions.
\n' +
'- Check out EIP 781:\n' +
'\n' +
'https://github.com/ethereum/EIPs/issues/781
\n' +
'
\n' +
'\n' +
'- Can you tell us more about ABI\n' +
'gen for statically typed contracts?
\n' +
'
\n' +
'\n' +
'- Contracts need to be checked at\n' +
'compile times to ensure parameters etc (strong instead of number or\n' +
'something like that) and being statically typed is much easier to\n' +
'check this.
\n' +
'- Inspired by geth\n' +
'tooling, and there are\n' +
'also some JS ones (salt-size etc) but were all very opinionated and\n' +
'made all sorts of assumptions about how you wanted to use your\n' +
'contracts.
\n' +
'- With 0x tool: Consensys is using\n' +
'it, Sybil (journalism tools, also with typescript\n' +
'contracts).
\n' +
'- Using ethers.js for backend of\n' +
'contracts due to issues with web3 versions (classic).
\n' +
'
\n' +
'\n' +
'- Best ideas to have in a\n' +
'debugger?
\n' +
'
\n' +
'\n' +
'- Not writing solidity actively at\n' +
'the moment and I haven’t used one yet because it is such a high\n' +
'level tool (haha).
\n' +
'- I feel that this is quite a long\n' +
'way away right now.
\n' +
'- Need bytecode, source code, source\n' +
'maps, traces, interruptable VM etc.
\n' +
'
\n' +
'\n' +
'- Can you tell us more about\n' +
'signing data in Ethereum?
\n' +
'
\n' +
'\n' +
'- Arbitrary string that people were\n' +
'supposed to sign, but then people figured that you could use it to\n' +
'send ETH, hence the weird prefix that got implemented - not an EIP,\n' +
'it is just a bugfix.
\n' +
'- If there is a way to display user\n' +
'data and get them to understand the transaction fully, then they\n' +
'would surely not sign. Prefix doesn’t solve anything, it just\n' +
'postpones the problem.
\n' +
'
\n' +
'\n' +
'
[a]WE can do more research here -- this is a big\n' +
'bounty
\n' +
'
Axel Ericsson
\n' +
'\n' +
'\n' +
'- What type of apps do you\n' +
'build?
\n' +
'
\n' +
'\n' +
'- 0x - Decentralized exchange\n' +
'protocol. It is a set of smart contracts that handle standard\n' +
'transactions in an order format.
\n' +
'
\n' +
'\n' +
'- The key advantage here is that\n' +
'these smart contracts leads to shared liquidity
\n' +
'
\n' +
'\n' +
'- We also achieve increased security\n' +
'and network liquidity through our architecture.
\n' +
'- We launched the network in August\n' +
'2017.
\n' +
'
\n' +
'\n' +
'- It works, but is V1. We are working\n' +
'on V2 which helps people build hybrid stations, supports new token\n' +
'standards, and makes the contract more gas efficient.
\n' +
'- V1 only allows humans to create\n' +
'orders; V2 will allow new smart contract to create orders. This is\n' +
'HUGE.
\n' +
'
\n' +
'\n' +
'- Notes:
\n' +
'
\n' +
'\n' +
'- We’re building the protocol;\n' +
'designing the standard; building dev tools for anyone to build a\n' +
'decentralized exchange.
\n' +
'
\n' +
'\n' +
'- Orders may become invalid for any\n' +
'reason:
\n' +
'
\n' +
'\n' +
'- Order being filled
\n' +
'- Griefing attacks
\n' +
'- We’ve now built an OrderWatcher\n' +
'that keeps relayers updated on the state of orders.
\n' +
'
\n' +
'\n' +
'- We’re using contract Events as a\n' +
'proxy for state changes.
\n' +
'- Can do a diff between state trees\n' +
'and between block headers.
\n' +
'
\n' +
'\n' +
'- We also have a set of smart\n' +
'contracts to handle settlement;
\n' +
'
\n' +
'\n' +
'- Everyone who wants to trade is\n' +
'setting allowances on a smart contract.
\n' +
'
\n' +
'\n' +
'- We want upgradability.
\n' +
'
\n' +
'\n' +
'- What are the\n' +
'tools/libraries/frameworks you use?
\n' +
'
\n' +
'\n' +
'- EthereumJS / truffle hardwallet\n' +
'provider / Typedoc (to generate documentation) /
\n' +
'- We don’t use Truffle\n' +
'anymore
\n' +
'
\n' +
'\n' +
'- Not reliable – can have race\n' +
'conditions;
\n' +
'- Artifacts don’t allow you to have\n' +
'versions of the contract on different networks
\n' +
'
\n' +
'\n' +
'- You don’t run into this stuff if\n' +
'you’re just building a “hello world”
\n' +
'
\n' +
'\n' +
'- Overwriting parts of the\n' +
'contracts;
\n' +
'
\n' +
'\n' +
'- We rolled our own. It’s open-source\n' +
'but not documented. We have other things that are keeping us\n' +
'busy.
\n' +
'- The problem is that Truffle has too\n' +
'much functionality –– we would like to see more of a Unix\n' +
'philosophy.
\n' +
'- Cannot support different versions\n' +
'of Solidity.
\n' +
'
\n' +
'\n' +
'- Version management doesn’t\n' +
'exist.
\n' +
'
\n' +
'\n' +
'- EthPM –– doesn’t have versioning\n' +
'either? It’s going through a big refactor, so we held off. We need\n' +
'the NPM package manager.
\n' +
'- We have built a lot of developer\n' +
'tools to interface with the smart contracts ourselves.
\n' +
'- We have also built own deployer and\n' +
'migration tool, as truffle’s did not suit our needs.
\n' +
'
\n' +
'\n' +
'- What are your biggest\n' +
'frustrations?
\n' +
'
\n' +
'\n' +
'- Getting a simple experimental\n' +
'environment up is hard
\n' +
'
\n' +
'\n' +
'- Remix is there; but it’s not\n' +
'enough.
\n' +
'
\n' +
'\n' +
'- Tracing and profiling is not\n' +
'existent.
\n' +
'
\n' +
'\n' +
'- Remix does it, but can’t do it\n' +
'locally.
\n' +
'- “Code coverage” tool exists but\n' +
'inserts console.logs in
\n' +
'
\n' +
'\n' +
'- Adding up gas costs per line of\n' +
'code.
\n' +
'
\n' +
'\n' +
'- Need to do profiling, because gas\n' +
'costs depend on inputs.
\n' +
'
\n' +
'\n' +
'- Solidity language\n' +
'itself:
\n' +
'
\n' +
'\n' +
'- Crashed the Solidity compiler twice\n' +
'today.
\n' +
'
\n' +
'\n' +
'- E.g. AbiEncoderV2 is pretty new and\n' +
'hard to understand/use.
\n' +
'
\n' +
'\n' +
'- The code that it produces is\n' +
'inefficient.
\n' +
'- There is a stark stack limit in\n' +
'solidity
\n' +
'
\n' +
'\n' +
'- All the variables are locally\n' +
'scoped.
\n' +
'- Un-intuitive as it is a curly\n' +
'braced language.
\n' +
'- The lifecycle hook value_of is\n' +
'within a function.
\n' +
'- Can only access top 16 slack slots.\n' +
'Including input and output.
\n' +
'- We need to implement a graph\n' +
'coloring register allocator – to find out what the lifetime of the\n' +
'variables is.
\n' +
'
\n' +
'\n' +
'- “This stack slot was used in the\n' +
'first half –– the second half you can use”
\n' +
'- Or implement register\n' +
'splitting.
\n' +
'
\n' +
'\n' +
'- Function inlining is frustrating\n' +
'sometimes:
\n' +
'
\n' +
'\n' +
'- E.g. SafeMath –– turns every\n' +
'operator into function call – which is a huge gas sink.
\n' +
'
\n' +
'\n' +
'- How Solidity optimizes could be\n' +
'improved:
\n' +
'
\n' +
'\n' +
'- It focuses on the code size (which\n' +
'makes sense since it’s minimizing the state tree); but sometimes\n' +
'you need to optimize size of tx gas (e.g. 0x needs optimized\n' +
'fillOrder call)
\n' +
'
\n' +
'\n' +
'- ABI doesn’t implement\n' +
'introspection
\n' +
'
\n' +
'\n' +
'- EIP 165
\n' +
'
\n' +
'\n' +
'- E.g. “does this contract implement\n' +
'ERC20, or ERC223?”
\n' +
'
\n' +
'\n' +
'- Solidity should have this\n' +
'in-built.
\n' +
'
\n' +
'\n' +
'- Should be built into the API spec\n' +
'and compiler.
\n' +
'
\n' +
'\n' +
'- Inheritance:
\n' +
'
\n' +
'\n' +
'- Interface or abstract contract –\n' +
'e.g. Solidity automatically creates getters for state functions ––\n' +
'collides with
\n' +
'- Contract which implements an\n' +
'interface – public or external for abstract functions – they\n' +
'collide
\n' +
'
\n' +
'\n' +
'- ERCs – there is not a formal way to\n' +
'describe the interface for contracts.
\n' +
'
\n' +
'\n' +
'- Have a standard repo –– this will\n' +
'lead to a canonical ABI definition –– can have semantic rules\n' +
'around this. Could run some specific unit tests against
\n' +
'
\n' +
'\n' +
'- How do you handle\n' +
'testing?
\n' +
'
\n' +
'\n' +
'- Testrpc has gotten better\n' +
'––
\n' +
'
\n' +
'\n' +
'- Increases the speed at which you\n' +
'can dev.
\n' +
'
\n' +
'\n' +
'- Blockstream is really cool. Written\n' +
'by Mica (from Augur?), under the EthereumJS lib.
\n' +
'- Good dealing with block re-orgs and\n' +
'changes in state.
\n' +
'- Continuous Integration:
\n' +
'
\n' +
'\n' +
'- Doesn’t really work for smart\n' +
'contracts.
\n' +
'- We just use testrpc.
\n' +
'- Neufund was different than\n' +
'0x:
\n' +
'
\n' +
'\n' +
'- Neufund was a trustee for tokens ––\n' +
'it was centralized by definition.
\n' +
'- This made it simpler: I could\n' +
'create “open-ended” contracts –– a switch statement, that the\n' +
'default would send to another proxy contract.
\n' +
'- But wouldn’t be able to do this\n' +
'with 0x –– e.g. if we wanted to add Shnorr signatures –– because\n' +
'it’s a governance / security issues.
\n' +
'
\n' +
'\n' +
'- How do you handle smart contract\n' +
'verification and security?
\n' +
'
\n' +
'\n' +
'- Code audits before\n' +
'deployment
\n' +
'- Want to add a formal verification\n' +
'tool to our deployment tool.
\n' +
'
\n' +
'\n' +
'- By analyzing the code, you can find\n' +
'patterns.
\n' +
'
\n' +
'\n' +
'- I manually did an audit in v0 of\n' +
'0x:
\n' +
'
\n' +
'\n' +
'- Make sure all functions have a\n' +
'“Read -> Write -> External Call” pattern, so you don’t have\n' +
'any race conditions.
\n' +
'
\n' +
'\n' +
'- Other bounties?
\n' +
'
\n' +
'\n' +
'- Rest of the bounties from\n' +
'Remco
\n' +
'- State-watching –– built-in\n' +
'diff’ing of state trees
\n' +
'
\n' +
'\n' +
'- Should be implemented in the\n' +
'Ethereum clients – Geth and Rust.
\n' +
'- They want this feature for\n' +
'OrderWatcher.
\n' +
'
\n' +
'\n' +
'- EIP process is\n' +
'suboptimal:
\n' +
'
\n' +
'\n' +
'- Lacks in consensus-building.\n' +
'There’s vocal people who don’t have good ideas; there’s a lot of\n' +
'noise.
\n' +
'- To improve: committee-based\n' +
'approach (reputable stakeholders from reputable projects who get\n' +
'together?).
\n' +
'- Problems are getting solved at the\n' +
'wrong abstraction level.
\n' +
'
\n' +
'\n' +
'- E.g. NFT standards.
\n' +
'
\n' +
'\n' +
'- Neufund was largest Solidity\n' +
'project before –– tokenized equity.
\n' +
'
\n' +
'\n' +
'- You want a EuroToken. You don’t\n' +
'want your company valuated in Ether.
\n' +
'- What if blockchain forks; which\n' +
'token is actually tied to the company?
\n' +
'
\n' +
'\n' +
'- Bounty approach gives many\n' +
'different styles within the codebase.
\n' +
'
\n' +
'\n' +
'- This is a problem; e.g. OpenSSL\n' +
'codebase after Masters / PhDs.
\n' +
'
\n' +
'',
},
{ id: 4,
name: 'Fernando Smith',
content: '\n' +
'Fernando Smith
\n' +
'\n' +
'\n' +
'- What type of apps do you\n' +
'build?
\n' +
'
\n' +
'\n' +
'- 0x - Decentralized exchange\n' +
'protocol. It is a set of smart contracts that handle standard\n' +
'transactions in an order format.
\n' +
'
\n' +
'\n' +
'- The key advantage here is that\n' +
'these smart contracts leads to shared liquidity
\n' +
'
\n' +
'\n' +
'- We also achieve increased security\n' +
'and network liquidity through our architecture.
\n' +
'- We launched the network in August\n' +
'2017.
\n' +
'
\n' +
'\n' +
'- It works, but is V1. We are working\n' +
'on V2 which helps people build hybrid stations, supports new token\n' +
'standards, and makes the contract more gas efficient.
\n' +
'- V1 only allows humans to create\n' +
'orders; V2 will allow new smart contract to create orders. This is\n' +
'HUGE.
\n' +
'
\n' +
'\n' +
'- Notes:
\n' +
'
\n' +
'\n' +
'- We’re building the protocol;\n' +
'designing the standard; building dev tools for anyone to build a\n' +
'decentralized exchange.
\n' +
'
\n' +
'\n' +
'- Orders may become invalid for any\n' +
'reason:
\n' +
'
\n' +
'\n' +
'- Order being filled
\n' +
'- Griefing attacks
\n' +
'- We’ve now built an OrderWatcher\n' +
'that keeps relayers updated on the state of orders.
\n' +
'
\n' +
'\n' +
'- We’re using contract Events as a\n' +
'proxy for state changes.
\n' +
'- Can do a diff between state trees\n' +
'and between block headers.
\n' +
'
\n' +
'\n' +
'- We also have a set of smart\n' +
'contracts to handle settlement;
\n' +
'
\n' +
'\n' +
'- Everyone who wants to trade is\n' +
'setting allowances on a smart contract.
\n' +
'
\n' +
'\n' +
'- We want upgradability.
\n' +
'
\n' +
'\n' +
'- What are the\n' +
'tools/libraries/frameworks you use?
\n' +
'
\n' +
'\n' +
'- EthereumJS / truffle hardwallet\n' +
'provider / Typedoc (to generate documentation) /
\n' +
'- We don’t use Truffle\n' +
'anymore
\n' +
'
\n' +
'\n' +
'- Not reliable – can have race\n' +
'conditions;
\n' +
'- Artifacts don’t allow you to have\n' +
'versions of the contract on different networks
\n' +
'
\n' +
'\n' +
'- You don’t run into this stuff if\n' +
'you’re just building a “hello world”
\n' +
'
\n' +
'\n' +
'- Overwriting parts of the\n' +
'contracts;
\n' +
'
\n' +
'\n' +
'- We rolled our own. It’s open-source\n' +
'but not documented. We have other things that are keeping us\n' +
'busy.
\n' +
'- The problem is that Truffle has too\n' +
'much functionality –– we would like to see more of a Unix\n' +
'philosophy.
\n' +
'- Cannot support different versions\n' +
'of Solidity.
\n' +
'
\n' +
'\n' +
'- Version management doesn’t\n' +
'exist.
\n' +
'
\n' +
'\n' +
'- EthPM –– doesn’t have versioning\n' +
'either? It’s going through a big refactor, so we held off. We need\n' +
'the NPM package manager.
\n' +
'- We have built a lot of developer\n' +
'tools to interface with the smart contracts ourselves.
\n' +
'- We have also built own deployer and\n' +
'migration tool, as truffle’s did not suit our needs.
\n' +
'
\n' +
'\n' +
'- What are your biggest\n' +
'frustrations?
\n' +
'
\n' +
'\n' +
'- Getting a simple experimental\n' +
'environment up is hard
\n' +
'
\n' +
'\n' +
'- Remix is there; but it’s not\n' +
'enough.
\n' +
'
\n' +
'\n' +
'- Tracing and profiling is not\n' +
'existent.
\n' +
'
\n' +
'\n' +
'- Remix does it, but can’t do it\n' +
'locally.
\n' +
'- “Code coverage” tool exists but\n' +
'inserts console.logs in
\n' +
'
\n' +
'\n' +
'- Adding up gas costs per line of\n' +
'code.
\n' +
'
\n' +
'\n' +
'- Need to do profiling, because gas\n' +
'costs depend on inputs.
\n' +
'
\n' +
'\n' +
'- Solidity language\n' +
'itself:
\n' +
'
\n' +
'\n' +
'- Crashed the Solidity compiler twice\n' +
'today.
\n' +
'
\n' +
'\n' +
'- E.g. AbiEncoderV2 is pretty new and\n' +
'hard to understand/use.
\n' +
'
\n' +
'\n' +
'- The code that it produces is\n' +
'inefficient.
\n' +
'- There is a stark stack limit in\n' +
'solidity
\n' +
'
\n' +
'\n' +
'- All the variables are locally\n' +
'scoped.
\n' +
'- Un-intuitive as it is a curly\n' +
'braced language.
\n' +
'- The lifecycle hook value_of is\n' +
'within a function.
\n' +
'- Can only access top 16 slack slots.\n' +
'Including input and output.
\n' +
'- We need to implement a graph\n' +
'coloring register allocator – to find out what the lifetime of the\n' +
'variables is.
\n' +
'
\n' +
'\n' +
'- “This stack slot was used in the\n' +
'first half –– the second half you can use”
\n' +
'- Or implement register\n' +
'splitting.
\n' +
'
\n' +
'\n' +
'- Function inlining is frustrating\n' +
'sometimes:
\n' +
'
\n' +
'\n' +
'- E.g. SafeMath –– turns every\n' +
'operator into function call – which is a huge gas sink.
\n' +
'
\n' +
'\n' +
'- How Solidity optimizes could be\n' +
'improved:
\n' +
'
\n' +
'\n' +
'- It focuses on the code size (which\n' +
'makes sense since it’s minimizing the state tree); but sometimes\n' +
'you need to optimize size of tx gas (e.g. 0x needs optimized\n' +
'fillOrder call)
\n' +
'
\n' +
'\n' +
'- ABI doesn’t implement\n' +
'introspection
\n' +
'
\n' +
'\n' +
'- EIP 165
\n' +
'
\n' +
'\n' +
'- E.g. “does this contract implement\n' +
'ERC20, or ERC223?”
\n' +
'
\n' +
'\n' +
'- Solidity should have this\n' +
'in-built.
\n' +
'
\n' +
'\n' +
'- Should be built into the API spec\n' +
'and compiler.
\n' +
'
\n' +
'\n' +
'- Inheritance:
\n' +
'
\n' +
'\n' +
'- Interface or abstract contract –\n' +
'e.g. Solidity automatically creates getters for state functions ––\n' +
'collides with
\n' +
'- Contract which implements an\n' +
'interface – public or external for abstract functions – they\n' +
'collide
\n' +
'
\n' +
'\n' +
'- ERCs – there is not a formal way to\n' +
'describe the interface for contracts.
\n' +
'
\n' +
'\n' +
'- Have a standard repo –– this will\n' +
'lead to a canonical ABI definition –– can have semantic rules\n' +
'around this. Could run some specific unit tests against
\n' +
'
\n' +
'\n' +
'- How do you handle\n' +
'testing?
\n' +
'
\n' +
'\n' +
'- Testrpc has gotten better\n' +
'––
\n' +
'
\n' +
'\n' +
'- Increases the speed at which you\n' +
'can dev.
\n' +
'
\n' +
'\n' +
'- Blockstream is really cool. Written\n' +
'by Mica (from Augur?), under the EthereumJS lib.
\n' +
'- Good dealing with block re-orgs and\n' +
'changes in state.
\n' +
'- Continuous Integration:
\n' +
'
\n' +
'\n' +
'- Doesn’t really work for smart\n' +
'contracts.
\n' +
'- We just use testrpc.
\n' +
'- Neufund was different than\n' +
'0x:
\n' +
'
\n' +
'\n' +
'- Neufund was a trustee for tokens ––\n' +
'it was centralized by definition.
\n' +
'- This made it simpler: I could\n' +
'create “open-ended” contracts –– a switch statement, that the\n' +
'default would send to another proxy contract.
\n' +
'- But wouldn’t be able to do this\n' +
'with 0x –– e.g. if we wanted to add Shnorr signatures –– because\n' +
'it’s a governance / security issues.
\n' +
'
\n' +
'\n' +
'- How do you handle smart contract\n' +
'verification and security?
\n' +
'
\n' +
'\n' +
'- Code audits before\n' +
'deployment
\n' +
'- Want to add a formal verification\n' +
'tool to our deployment tool.
\n' +
'
\n' +
'\n' +
'- By analyzing the code, you can find\n' +
'patterns.
\n' +
'
\n' +
'\n' +
'- I manually did an audit in v0 of\n' +
'0x:
\n' +
'
\n' +
'\n' +
'- Make sure all functions have a\n' +
'“Read -> Write -> External Call” pattern, so you don’t have\n' +
'any race conditions.
\n' +
'
\n' +
'\n' +
'- Other bounties?
\n' +
'
\n' +
'\n' +
'- Rest of the bounties from\n' +
'Remco
\n' +
'- State-watching –– built-in\n' +
'diff’ing of state trees
\n' +
'
\n' +
'\n' +
'- Should be implemented in the\n' +
'Ethereum clients – Geth and Rust.
\n' +
'- They want this feature for\n' +
'OrderWatcher.
\n' +
'
\n' +
'\n' +
'- EIP process is\n' +
'suboptimal:
\n' +
'
\n' +
'\n' +
'- Lacks in consensus-building.\n' +
'There’s vocal people who don’t have good ideas; there’s a lot of\n' +
'noise.
\n' +
'- To improve: committee-based\n' +
'approach (reputable stakeholders from reputable projects who get\n' +
'together?).
\n' +
'- Problems are getting solved at the\n' +
'wrong abstraction level.
\n' +
'
\n' +
'\n' +
'- E.g. NFT standards.
\n' +
'
\n' +
'\n' +
'- Neufund was largest Solidity\n' +
'project before –– tokenized equity.
\n' +
'
\n' +
'\n' +
'- You want a EuroToken. You don’t\n' +
'want your company valuated in Ether.
\n' +
'- What if blockchain forks; which\n' +
'token is actually tied to the company?
\n' +
'
\n' +
'\n' +
'- Bounty approach gives many\n' +
'different styles within the codebase.
\n' +
'
\n' +
'\n' +
'- This is a problem; e.g. OpenSSL\n' +
'codebase after Masters / PhDs.
\n' +
'
\n' +
'',
},
];
export default data;