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April 28, 2020
Cadence Cup Round 3: Resources Owning Other Resources
Cadence Cup Round 3: Resources Owning Other Resources

Cadence Cup Round 3 is Here.

Welcome back to Cadence Cup. Round 1 brought some wacky NFT minting action, where the winning project was a Shadowrun inspired game in Cadence that used resources in surprising ways: users created characters that could hold many different kinds of items, all represented by resources, and allowed other participants to create games for those characters. 

Round 2 brought some very interesting voting strategies. Among them, the thoughtfulness that went into this Art Voting contract was off the charts. Their design allowed voters to receive fractionalized ownership of the art they voted for, which could be a powerful incentive mechanism to promote broader participation and diversity in art discovery. The team is truly impressed by the amazing ideas that community has been coming up with.

As usual, it isn’t required to have completed the first or second rounds of Cadence Cup to participate in Round 3. This is your opportunity to join, show off your skills and, most importantly, your creativity! 

For this challenge, explore the possibilities of resources owning other resources. This is a unique feature native to Cadence. Resource objects can store other objects inside of them, making it possible for a resource (or account) to effectively own multiple resource objects directly (not simply a list mapping on a smart contract). This allows you to see all the objects a resource owns just by looking inside it, instead of trying to parse across a bunch of different smart contracts and ledgers. 

For example, this can be useful with an application like KittyHats, the NFTCollection that holds NFTs inside of it, or even combining resources of car parts into a customizable resource object. (@WittyKitty, @KittyPad, @Queen Cryptoria, and @Dennis created a game that did this for the first challenge and it was really cool!)

Check out the Kitty Hat tutorial to see a simple version of this in action!

Demonstrate what you can do to make the most effective and creative use of this unique feature of Cadence. This can be any kind of smart contract you want. It could be another Voting contract, NFT contract, game or anything else. Show your creativity at work!

Start Date for Round 3 Challenge: April 28, 2020

End Date for Round 3 Challenge: May 19, 2020 (11:59 PM PST)



Judges will score each project on readability, effectiveness, and creativity. The team will be there to assist you along the way. If you have any questions during this challenge, please post them in the #cadencecup channel on Discord.

Rules of Cadence Cup

The project with the highest amount of points at the end of each round wins a prize for that round.

Members of the Flow team, and sometimes prominent members of the community, will give each project a score based on: readability, effectiveness, and creativity of the contract: 5 points for legit participation, 7 points for submitting a good project, 10 points for a win.

Prizes of Cadence Cup

  • Each round, the winning project will receive a Cadence Builder Kitty
  • At the end of three rounds, the individual with the highest score will receive $2500
  • If you submit a project every round and receive a combined score of 20 and above, you'll also receive a Cadence Builder Kitty

The community is always willing to answer your questions and even give you some pointers on your idea if you need help. 

Don’t forget to share your journey on Twitter and tag us @flow_blockchain!

If you need help you can connect with us on Discord.