Unofficial Scroll ZK EVM Code Review

1. Unofficial Scroll ZK EVM Code Review https://linktr.ee/alexcj96
2. Summary - Why ZK EVM works? - Architecture - Tech stack comparaison - Arithmetization - Trace generation - Gate configuration - Circuit tools - Some opcode gadgets - Public input circuit - Synthesize - Combining with halo2 - Observation
3. Why ZK EVM works? ❖ EVM is a State Machine ❖ Public-key cryptography ➢ Verify txs all represent users' intention ❖ Blockchain consensus ➢ Verifier ➢ Previous state root ❖ MPT ➢ Verify initial state ➢ Verify new root ❖ ZK ➢ Succinctness ➢ Lookup Arguments ❖ Ethereum as a DA Layer
4. Architecture
5. Tech stack comparaison
6. Arithmetization
7. Trace generation - flow (scroll has simplified this)
8. Trace generation - types (simplified)
9. Gate configuration - flow
10. Gate configuration - gadgets Add cb constraints etc
11. Gate configuration - lookup
12. Circuit tools - cell manager
13. Circuit tools - constraint builder
14. Circuit tools - constraint builder
15. Circuit tools - utils
16. Some opcode gadgets - AddSub
17. Some opcode gadgets - ReturnRevert (simplified)
18. Public input circuit
19. Public input circuit
20. Synthesize
21. Combining with halo2
22. Combining with halo2
23. Observation - Scroll doesn’t support self destruct EVM opcode - Scroll’s MPT tree uses poseidon circuit - Scroll uses chain_id and block_number to calculate block_hash!!! - Scroll still uses SuperCircuit which is very zk-unfriendly - Don’t read PSE’s code, it’s not production ready!!! - …
24. Thanks!