Should I Stay Or Should I Go?

He who jumps into the void owes no explanation to those who stand and watch.

Jean-Luc Godard

Money vs satisfaction. The known vs the unknown. Safe(ish) vs safe. These are the kind of trade-offs that go through my mind when I evaluate whether to stay in my current job or not.

It’s all about the money, money, money – until it’s not! Getting paid reasonably well to work in an unsatisfactory environment isn’t enough.

So what is enough 🤔? There’s been some interesting information on this subject, most recently one that struck a chord was by Fred Wilson in his post What To Work On. A checklist of his suggestions are projects that:

  • Interests
  • Motivates
  • Inspires
  • Impactful

Realistically in my current role the last three no longer apply. The last could be a yes. The available options all appear to be a yes although there’s always the risk that the vision is different from the reality.

Some more advice to help zero in on specifics are from this post and include:

  • Do you know what you want to get out of the next chapter – mmmh, specifics are tricky! I think I’d like to build my knowledge and skills in the blockchain and development world. It’s also important to gain access to people and opportunities in this industry. A sketchy final goal is to do something myself some day.
  • What are your side constraints – Ideally I want to stay in my current location, remote work would be fine. I’d like to work with professional, inspirational people that are focused and knowledgeable and are willing to let me soak up as much as I can! Getting paid well would be a bonus but I will accept below market rates for the right opportunity.
  • How much risk will I take – I guess I’m pretty open to risk really. I would probably prefer a startup because there’s more opportunity to make an impact and learn. I’m also considering being a student. Joining a post product-market fit start-up that is already scaling rapidly is the advice but I don’t think there’s many of these available right now. One of my biggest risk fears is trading one bad for another! Another is being ‘all in’ on blockchain – what if it ALL goes tits up?! I don’t think either are big enough risks to emergency stop.

As I type it becomes clear – mentally I’m already gone! I just hope I ‘go’ to the right thing. How awesome, inspirational and cool is the below quote from Preston Van Loon – that sounds like the right thing to me!

We are strong believers in Ethereum for a major reason – it is a fully permissionless blockchain that allows anyone to build unstoppable, censorship-resistant applications. In the beginning, we were all independent software engineers that shared a passion for the Ethereum blockchain, searching for the best way to contribute to its future. Now, we work full time on making the next iteration of the Ethereum project a reality. The fact that such a story is allowed to happen is a testament to the Ethereum project’s meritocracy and its community. We love to code, and being able to wake up each morning and work on fun, challenging, and meaningful problems is one of the best things anyone in this field could ask for. This is the best possible time to shape the future of Ethereum, and we’re privileged to have the support of you all to do so.
We believe in code quality, maintainability, and good design, and tests as our key pillars over anything else. Additionally, we believe there is a lack of industry best practice and sound software design in Ethereum development. A lot of the pain eth1 suffered came from reinventing many key pieces of its architecture, such as a custom json-rpc, a completely new, custom p2p library, etc. instead of adopting practices present in industry for years. An open source project needs to have longevity, and having easy readability + great tests ensures new contributors can pick up where we left off and keep the project growing at the same pace. When building the infrastructure that will maintain a major, multi-billion dollar project, every line of code we write must be considered with great care and consideration. Protocol development for Ethereum should be the opposite of what “hackathon”-style code looks like, and more importantly, we believe every developer should spend twice as much time reviewing code as writing it. We see many other projects write code that is really clever at the cost of being unintelligible to most, and that goes against our ethos. We chose Go because it is a language that prefers being clear and simple over being witty and complex, and Go as a language resonates well with our philosophy towards software engineering. Every time someone aims to make some code more clever or “concise” using fancy tricks or attempting to cram key logic into as few lines of code as possible, we avoid doing the same, as that’s not what good software should be about.
Ethereum 2.0 will eventually just be Ethereum, otherwise, the entire effort would have failed massively! We definitely see ourselves as a key team within the Ethereum community, building important tooling and infrastructure for its users, companies, and dApps building on the protocol. We have a responsibility to increase its adoption and keep improving the project over time. We believe Ethereum will keep creating a lot more valuable projects on top of it, and perhaps in the future we will create our own product on top of Ethereum itself, but with the key goal of always furthering its vision.

EthFinanace AMA Series with Prysmatic Labs

🤓 Geeking Out On Uniswap 🦄

Uniswap is a simple smart contract interface for swapping ERC20 tokens and in general it’s pretty awesome. The story behind it is really inspirational to me and just recently Hayden Adams tweeted that $10million of liquidity was added in a 24 hour period – surely pretty succesful by any measure!

Some of the features of Uniswap include:

  • Supplies on-chain liquidity to other smart contracts
  • Ease of use
  • Gas efficiency (10x less than Bancor)
  • Decentralised/censorship resistant

And just as a reminder:

Liquidity describes the degree to which an asset or security can be quickly bought or sold in the market at a price reflecting its intrinsic value.

Investopedia

Each Uniswap pool holds Eth and another token and trades are exectuted against these reserves.

By supplying tokens to the pooled reserve (being a liquidity provider) you get a proportional share of transaction fees via a liquidity token.

Prices are set automatically using eqn: x * y = k or in terms of tokens: eth_pool * token_pool = invariant.

The invariant is constant during trades but DOES change when liquidity is added or removed from pool. (So not really an invariant?!)

Liquidity Tokens

Liquidity tokens are minted to track the relative proportion of total reserves that each liquidity provider has supplied.

Fees are taken during a token swap and are added to the liquidity reserves. Since total reserves are increased without adding any additional share tokens, this increases that value of all liquidity tokens equally. This functions as a payout to liquidity providers that can be collected by burning shares. (It’s also the reason that the invariant increases at the end of every trade)

When a liquidity provider joins the pool the amount of liquidity tokens minted are calcualted by:

(Initial pool liquidity is equal to initial Eth value provided)
total_liquidity = self.totalSupply
eth_reserve = self.balance - msg.value
liquidity_minted = msg.value * total_liquidity / eth_reserve

Liqudity tokens can be burned at any time to return a proportional share of the markets liquidity to the provider:

removeLiquidity(amount...):

total_liquidity = self.totalSupply
token_reserve = self.token.balanceOf(self)
eth_amount = amount * self.balance / total_liquidity
token_amount = amount * token_reserve / total_liquidity

self.balances[msg.sender] -= amount
self.totalSupply = total_liquidity - amount
send(msg.sender, eth_amount)
return eth_amount, token_amount

Exchanging

Eth -> Token: Traders Eth is added to pool and Token is removed. So Eth amount increases, token amount decreases. Token becomes more expensive.

Token -> Eth: Traders Token is added to pool and Eth is removed. So Eth amount decreases, token amound decreases. Eth becomes more expensive.

Arbitrage

Arbitrage seems to be the key to so many DeFi applications! I think the following is nice description of what it is:

Arbitrage trading is a strategy that can be best understood as a trader that takes advantage of the price differential that exists between two markets. In the case of cryptocurrency, this price differential can be found in the differences in price of a digital asset between cryptocurrency exchanges. If a trader identified an opportunity for arbitrage trading, then they would purchase a digital asset in one exchange, and then sell it on another cryptocurrency exchange.

Mycryptopedia

To me it’s all about icentives – basically in the form of greed! There’s always someone looking to make money from an opportunity. In this case they execute a trade to make a profit but by making they trade they change the price which basically corrects it to the market price – that’s cool!

For example:

  • the global price of ETH-USD moves enough away from the pool price, an arbitrage opportunity exists and is corrected
  • When the initial liquidity is provided the exchange rate is set. If the ratio of liquidity provided isn’t realistic arbitrage traders will correct at the expense of initial liquidity provider.

Some Examples With Numbers

Invariant is set on initial deposit to a new pool. For example 10 ETH and 500 FUN are deposited into new ETH/FUN pool. Invariant is set to:

ETH_pool * FUN_pool = invariant
10 * 500 = 5000

Now for an ETH -> FUN trade:

Buyer sends 1ETH

Fee = 1 ETH / 400 = 0.0025 ETH (0.25% fee)

ETH_pool = 10 + 1 - 0.0025 = 10.9975

FUN_pool = 5000/10.9975 = 454.65 (invariant/ETH_pool)

Buyer receives: 500 - 454.65 = 45.35 FUN

Fee is added back to pool:

ETH_pool = 10.9975 + 0.0025 = 11

FUN_pool = 454.65

New invariant = 11 * 454.65 = 5001.15

Executed price = 45.35 FUN/ETH

But now price has changed:

Fee = 0.0025 ETH
ETH_pool = 11.9975
FUN_pool = 5001.15/11.9975 = 416.85
Buyer receives: 454.65 - 416.85 = 37.8

Executed price = 37.8 FUN/ETH

Price Slippage

Price slippage refers to the difference between the expected price before a transaction is executed and the actual price at which it is executed.

Bancor Support

Easiest for me to think of spot price and actual price.

A trade that is large relative to the size of the total size of the liquidity pool will cause price slippage.

Same example as above: 
ETH_pool * FUN_pool = invariant
10 * 500 = 5000

Spot price for ETH -> FUN = 500/10 = 50

1ETH Purchase: Executed price = 45.35 FUN/ETH

10ETH Purchase: Executed price = 24.969 FUN/ETH

Fee = 10 ETH / 400 = 0.025 ETH (0.25% fee)

ETH_pool = 10 + 10 - 0.025 = 19.975

FUN_pool = 5000/19.975 = 250.31

Buyer receives: 500 - 250.31 = 249.69 FUN

Fee is added back to pool:

ETH_pool = 19.975 + 0.025 = 20

FUN_pool = 250.31

New invariant = 20 * 250.31 = 5006.2

Executed price = 24.969 FUN/ETH

Final Thought

I found this comment from Vitalik on this EthResearch post interesting:

The point is not for this kind of exchange to be the only exchange; the point is for it to be one type among many. It offers the benefits of executing a complete trade in one transaction, and extreme user-friendliness even to smart contracts, which are very real benefits and will at least sometimes exceed the costs of slippage to some users. I am ok with just accepting that this kind of approach will not be acceptable to whales who want to liquidate large amounts of things; that’s not the target market.

(A lot of this stuff came from the Uniswap White paper. Photo by James Lee on Unsplash)

Solidity – How To Estimate Gas Costs

I’ve been working on optimizing the gas cost for deploying a smart contract. Turns out truffle has some pretty useful ways of estimating gas used.

Good Old Migrate

The most obvious way is to just run $ truffle migrate and see what the output says. When the project has quite a large build this can take some time so it’s not that efficient for seeing the difference some code changes make. I do find it useful to run this every now and again though just to confirm the estimates are correct.

estimateGas()

The other way I found useful is to use the estimateGas function. As is pretty self explanatory it is just an estimate and could change depending on the contract state. I found this was nice and quick to use on a truffle cli and I found two useful estimations to look at:

Contract deployment

Start the local ganache with a large gas limit:

$ ganache-cli --gasLimit 10000000 --allowUnlimitedContractSize

Start a truffle cli that connects to above chain:

$ truffle console

Estimate gas for deploying your contract:

truffle(develop)> YourContract.new.estimateGas()

Calling Contract Method

Start with the same set-up steps as above. Then:

truffle(develop)>  YourContract.testMethod.estimateGas()

And that’s it – another useful trick!

Migrating SAI to DAI

I was using Dharma.io to earn interest on my SAI (formerly DAI). I found Dharma really nice to use and originally offered a good interest rate. Recently the rate had become less competitive and I was getting concerned (maybe unneccesarily?) about the lack of comms about migrating the SAI to DAI so I decided to take matters into my own hands especially now that the DAI Savings Rate has kicked in.

When I swapped I was getting 3.22% for SAI on Dharma.io. The DAI savings rate is 4% and looks like it might get raised to 6% soon so definitely worth the swap.

  1. Visit https://migrate.makerdao.com/
  2. Unlock SAI. This calls the approve function for the token. (Nice explanation here.)
  3. This had a gas cost of 0.002637ETH, $0.35.
  4. That was it – once I checked my account I could see DAI.
  5. Not to earn some interest.
  6. Click earn savings. This navigates to https://oasis.app/save.
  7. Deploy Proxy – Setting up your proxy will bundle multiple transactions into one, saving transaction time and gas costs. This only has to be done once.
  8. Gas cost: 0.007344ETH, $0.97
  9. Now wait for 10 confirmations.
  10. Approve Oasis for DAI.
  11. 0.00055ETH, $0.07
  12. Finally deposit the DAI.
  13. 0.002713ETH, $0.36

Total cost $1.75. And now it’s quite satisfying to watch my depost earn interest in real time!

(Photo by Fabian Blank on Unsplash)