What is SewUp

• Rust
• Open source at Github
• Contract Dev as Backend

Is contract good enough

for  Web 3?

Where is the gap

• Security
• Too low level
• Too many domain knowledge

How to Sew Up

• Security
• Too low level
• Too many domain knowledge

Rust

Contract Dev as Backend

Rust in Contract

• ewasm-rust-api
• Version 0.11.0 (2019 Nov 27)

Pain point eWasm with Rust

• Not really Rusty API

  • Result

  • Option

• Operating in low-level

  • operate on Bytes32

  • Manually handle functional signature
• Not easy to test with cargo test

This is C

pub enum CallResult {
    Successful,
    Failure,
    Revert,
    Unknown,
}

This is Rust

pub enum CallError {
    Failure,
    Revert,
    Unknown,
}

fn call() -> CallResult;

fn call() -> Result<(), CallError>;

Please read things behind the wordings!

The goal of Sewup

ewasm-rust-api

sewup

• Rusty API

  • Result

  • Option

  • Error

• high level operation

  • like handle KV db

  • functional signature macro
  • no more byte operation
• Easy to test with cargo test

• Customize error
• Good error message
• Easy to use

match your funtion

Rust style result

structure

bytes

string

store without touching Bytes32

Keep working

• Function Inputs (v0.0.2)
• Function outputs (v0.0.2)
• Update mutated Bytes32(Raw) only

• from contract caller
  • runtime inputs
• from contract developer
  • compile time inputs
• tools for generate input data

• Rusty
  • return a Result
• Non-Rusty
  • return T for Result<T>
• Return
  • from main
  • from handler

Last but not least

Blockchain bring TRUST to the world

Rust is the stem of TRUST

Thanks for listening

Star the project if you like it

https://github.com/second-state/SewUp

There are also help want issues and good first issues

Interested in VM?

WasmEdge is welcom to contribute

https://github.com/WasmEdge/WasmEdge

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