Digital🛢- Will you strike digital oil? — Issue #7 — The Best Joke Teller 🥁 & The Last Task

3 min readMar 17, 2022

Digital🛢(oil) is a brand-new scavenger hunt newsletter that pays you to learn about blockchains. At the end of the month you’re eligible to strike digital oil ($500 paid in USDC) if you complete all checkpoints. Solve quick (2–3 min) and simple (easy) tasks that arrive in your inbox weekly, designed to teach you how to interact with blockchains. A smart contract will select one eligible address at random every month and will send $500 in USDC to the winning address.

We have a Joke Telling Contest Winner 🥁

A few moments ago I closed voting for the joke telling contest. We have a winner!

We had a total of 14 voters, which means 14 people completed the 3rd task in Oil Strike #1. The vote transactions can be seen here on PolygonScan. The winning joke received 3 votes.

And… the winner’s Polygon address is:


I’ve shown you how to write (or transact) with a smart contract through the PolygonScan interface, but haven’t shown you how to read from the contract. In order to inspect that that address was indeed the best joke teller, you can verify that the smart contract truly selected it by going here and looking for the section 2 called bestJokeTeller. That is the the variable where the winning address is stored.

The Winning Joke

And… the winning joke was:

Batman invited all the superheroes to an evening discussing bitcoin investments, Superman didn’t go because it was a crypto-night.

The Last Task

It is now time for you to realize your last task. This task enrolls you in the raffle for the $500 in USDC. I have opened raffle enrollment in the smart contract, which also automatically closes voting. This means that no more than 14 people can enter the raffle since only that many completed Task #3.

To enter the raffle, go here and go to section 3 (enterRaffle) and click the Write button, and then confirm the transaction when Metamask pops up. I’m proud to know that I don’t need to show you step by step screenshots now because you’ve all passed the novice stage of interacting with blockchains.

I’ll give you about a week to enter the raffle. Then, I will click on drawRaffle and the smart contract will pseudorandomly select a winner who will automatically be sent the USDC prize. If all 14 eligible participants enter the raffle, you have a 7.1% chance of winning $500.

Some Bonus Content: A Primer on USDC

So, what is USDC?

USDC is a stablecoin, meaning a cryptocurrency that is pegged to the US Dollar. The coins are born in a smart contract (ERC20, in case you are familiar) on Ethereum, owned by Coinbase. The way it works is that you ask Coinbase to convert the US Dollars that you have deposited on their platform to crypto dollars that allow you to interact with smart contracts. For every dollar you “convert” (in reality Coinbase just keeps it in their treasury), they mint a new USDC coin in their smart contract and they assign it to your Ethereum address. When you want your US Dollars back, you ask them to burn the USDC you have and assign the equivalent number of US Dollars to your Coinbase account, which you can wire out when you wish.

But the USDC you send us isn’t on Ethereum; it’s on Polygon

That’s right. It turns out you can bridge USDC from Ethereum to Polygon. I won’t get into the mechanics of this, but I’ll say that in case you need to transact using USDC on Polygon you can and they are equivalent to USDC on Ethereum. Actually, if you ever want to cash out the USDC on Polygon, at the moment, the simplest way is to bridge them back to Ethereum, and then send them to an online crypto brokerage which accepts Ethereum USDC, and then ask them to send you the US Dollars. Alternatively, you can pay other people for services using USDC on Polygon by sending to their Polygon address; or you can interact with smart contracts on Polygon with your USDC. For example, you can exchange USDC for MATIC or any other currency to buy NFTs or play games on Polygon that require upfront investments (like buying an NFT to play).

One of My Tweets

My thoughts on Web3 and the centralized vs decentralized discussion:

See you next week for the reveal of the prize winner!






Early. Ethereum dev and founder @nft_registry . Podcast host @0xCryptoLatinos . Business director. Former ios dev & satcom engineer. @GeorgiaTech ee & @mit