This document provides an overview of StarkNet, a validity rollup platform that enables fast and scalable transactions on Ethereum. It discusses availability rollups and their tradeoffs between speed and inclusiveness. It introduces StarkNet's use of ZK-STARK proofs to enable fast, inclusive transactions while maintaining security. It also provides details on developing applications for StarkNet using the Cairo programming language, examples of projects being built on StarkNet, and resources for learning more.

1. Fun with ERC721 on StarkNet
Henri Lieutaud / Developer advocate
January 2022
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@henrilieutaud | @starkwareltd

2. Availability rollups primer

3. Slow, inclusive
Fast, exclusive
Current State of Affairs
Trust Big Computer Verify (all transactions), don’t trust

4. Increase Scale (gas/block limit) Fraud Proof Rollups (Arbitrum, Optimism)
Fast, exclusive
Trust Big Computer Trust a few Big Computers
Fast, semi inclusive

5. Validity Proofs (StarkNet, zkSync)
Big computer to generate proof
Expensive, semi inclusive (~mining) Fast, inclusive
Small computer to verify proof
ZK-STARK
proof

6. *With respect to size of computation
Privacy (Zero Knowledge, ZK)
Prover’s private inputs are shielded
Scalability
Exponentially small verifier running time*
Nearly linear prover running time*
Prover verifier
v
π
ZK-STARK Proofs
Verify (all transactions), don’t trust

7. *With respect to size of computation
Privacy (Zero Knowledge, ZK)
Prover’s private inputs are shielded
Scalability
Exponentially small verifier running time*
Nearly linear prover running time*
Prover
Verify STARK proof, don’t trust
π, Statenew
ZK-STARK
v
v
v
v
v
v
π, Statenew
π, Statenew
π, Statenew
π, Statenew
π, Statenew
π, Statenew
ZK-STARK Proofs

8. Two L2 Offerings
Largest L2 by TPS
(¼ Ethereum’s, on the rise)
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@henrilieutaud | @starkwareltd

9. $270B 65M $1.25B
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Launched - June 2020
10M
NFTs Minted
Tx Settled
600K
NFT Mints/Proof
Total Value Locked
Cumulative Trading
486
Gas/tx
As of December 9, 2021
@henrilieutaud | @starkwareltd

10. Launched November 29, since then:
● StarkNet Developer Discord exploding:
○ 20K users, 3K joined last week
○ 2K weekly active users
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● 20+ teams building dApps, including:
○ 3 AMMs
○ Games, NFT projects
○ Voting, bridges, and more
Ethereum-style permissionless interaction with the network

11. Developing on StarkNet

12. Cairo
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● Specially designed, provable language, dedicated for Smart Contracts
● Cairo is not bounded by the EVM
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Syntax tutorial on GitHub
➔ Coming soon: Solidity -> Cairo transpiler

13. Standard implementations
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● Open Zeppelin - developing a set of boiler plate smart contracts for Cairo
○ Today - use an implementation included in therepo (courtesy of Oasis)
● Cairo standards reuse Solidity standards - naming convention for external functions
Boiler plate smart contracts are great or StarkNet onboarding!

14. Importing functions
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● The importing pattern is not enforced by the compiler, and is being discussed by the community
○ Base contracts define core functions. They have no external functions and no constructor
○ Front end contracts import internal functions from base contracts, and wrap them in
external functions
Impot Functions Inherit Functions

15. Account abstraction
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@henrilieutaud | @starkwareltd
● Transactions on StarkNet are different than Ethereum - they do not have an originator (“From”)
● They are sent to an “entry point” - an “account smart contract” in charge of:
○ Authenticating the user
○ Replay protection
○ Funds protection
○ Allows many different UX to be built upon
● This is not currently enforced
○ transactions can be sent to any contract, while the sender is seen as 0 by the receiver

16. Integrated Development Environments
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3 main tools to interact with StarkNet:
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*All three are under development and require duct tape here and there
Today’s tutorial is based on Nile
HardHat
(Javascript)
StarkNet
CLI
Nile
(Python)

17. briq
The NFT building protocol

18. this but
literally

19. use use your NFTs in a growing metaverse
build
continue to create by disassembling NFTs back into briqs
your own NFTs with briqs

21. - Online briq builder available
- ERC721 briq & set contracts
deployed on StarkNet mainnet &
testnet
- +1k NFT creations, 2.5K followers
briq alpha
first NFT project deployed
on StarkNet mainnet

22. - Difficult language but generally
good feedback from the compiler
- Math-heavy logic is particularly
tricky because of field
- Ecosystem is growing nicely
- Devnet wallet, Nile, …
- Lots of public interest
Feedback
first NFT project deployed
on StarkNet mainnet

23. Github: github/briqNFT
Twitter: @briqNFT
Sylve: @sylvechv
Lancelot: @wraitii

24. Getting to work

25. ERC721 Workshop
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Your objective - gather points.
Follow these steps to collect all points
1. Read the ReadMe for a high level understanding
2. Read the valuator.cairo code for a low level understanding
3. Use the ERC721 code and customize it
4. Deploy your contract
5. Submit your contract address to the evaluator
6. Ask the evaluator to correct your contract
7. Check for points
@henrilieutaud | @starkwareltd
Go to Github:

26. Thanks!
January 2022
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@henrilieutaud | @starkwareltd
Henri Lieutaud / Developer Advocate

27. To go further
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Jobs
- Dapp Developer at Shard labs.
- Open source developer at Open Zeppelin.
- Cairo engineers at Immutable.
- Chainlink integration team.
- Blockchain software engineer at JellyFi.
Resources on StarkNet
- Official Cairo documentation
- Community links - list of examples
curated by the StarkWare team
- Awesome StarkNet - a curated list of
resources by Georgios Konstantopoulos
Cool stuff built on StarkNet
- Physics simulation by @guiltygyoza
- briq V1 contracts
- Qasr, an ETH <> StarkNet NFT bridge
- Tictactoe by @guiltygyoza
@henrilieutaud | @starkwareltd