Provides a way of reading a real Starknet State, so you can re-execute an existing transaction in any of the Starknet networks in an easy way

• Linux or macOS (aarch64 included) only for now
• LLVM 19 with MLIR
• Rust 1.78.0 or later, since cairo-native makes use of the u128 abi change.
• Git

Run the following make target to install dependencies:

make deps

It will automatically install LLVM 19 with MLIR on macos, if you are using linux you must do it manually. On debian, you can use apt.llvm.org, or build it from source.

This project is integrated with Cairo Native, see Cairo Native Setup to set it up correctly

Some environment variable are needed, you can automatically set them by sourcing env.sh. If the script doesn't adjust to your specific environment you can cp it into .env or .envrc and modify it.

# Cairo Native
export LLVM_SYS_191_PREFIX=/path/to/llvm-19
export MLIR_SYS_190_PREFIX=/path/to/llvm-19
export TABLEGEN_190_PREFIX=/path/to/llvm-19
export CAIRO_NATIVE_RUNTIME_LIBRARY=/path/to/cairo_native/target/release/libcairo_native_runtime.a
# RPC
export RPC_ENDPOINT_MAINNET=rpc.endpoint.mainnet.com
export RPC_ENDPOINT_TESTNET=rpc.endpoint.testnet.com

Once you have installed dependencies and set the needed environment variables, you can build the project and run the tests:

make build
make test

Starknet Replay is currenlty integrated with Cairo Native, which makes the execution of sierra programs possible through native machine code. To use it, the following needs to be setup:

• On mac with brew, running make deps should have installed LLVM 19 with MLIR, otherwise, you must install it manually. On Debian, you can use apt.llvm.org, or build it from source.

• The LLVM_SYS_191_PREFIX, MLIR_SYS_190_PREFIX and TABLEGEN_190_PREFIX environment variable needs to point to said installation. In macOS, run:

  export LLVM_SYS_190_PREFIX=/opt/homebrew/opt/llvm@19
  export MLIR_SYS_191_PREFIX=/opt/homebrew/opt/llvm@19
  export TABLEGEN_190_PREFIX=/opt/homebrew/opt/llvm@19
  

  and you're set.

Afterwards, compiling with the feature flag cairo-native will enable native execution. You can check out some example test code that uses it under tests/cairo_native.rs.

Currently cairo-native with AOT needs a runtime library in a known place. For this you need to compile the cairo-native-runtime crate and point the following environment variable to a folder containing the dynamic library. The path must be an absolute path.

CAIRO_NATIVE_RUNTIME_LIBRARY=/absolute/path/to/cairo-native/target/release/libcairo_native_runtime.a

If you don't do this you will get a linker error when using AOT.

You can use the replay crate to execute transactions or blocks via the CLI. For example:

* cargo run tx 0x04ba569a40a866fd1cbb2f3d3ba37ef68fb91267a4931a377d6acc6e5a854f9a mainnet 648461
* cargo run block mainnet 648655
* cargo run block-range 90000 90002 mainnet

To run benchmarks with the replay crate, you can use either bench-block-range or bench-tx commands. These make sure to cache all needed information (including cairo native compilation) before the actual execution. To use it you must compile the binary under the benchmark flag.

* cargo run --features benchmark bench-tx 0x04ba569a40a866fd1cbb2f3d3ba37ef68fb91267a4931a377d6acc6e5a854f9a mainnet 648461 1
* cargo run --features benchmark bench-block-range 90000 90002 mainnet 1

These commands are like tx and block-range commands, but with the number of runs to execute as their last argument.

This projects uses tracing with env-filter, so logging can be modified by the RUST_LOG environment variable. By default, only info events from the replay crate are shown.

As an example, to show only error messages from the replay crate, run:

RUST_LOG=replay=error cargo run block mainnet 648461

To compare Native execution with the VM, you can use the state_dump feature. It will save to disk the execution info and state diff of every contract executed.

• If executing Native, the dumps will be saved at: state_dumps/native/block{block_number}/{tx_hash}.json
• If paired with only_cairo_vm feature, the dumps will be saved at: state_dumps/vm/block{block_number}/{tx_hash}.json

To compare the outputs, you can use the following scripts. Some of them required delta (modern diff).

• cmp_state_dumps.sh. Prints which transactions match with the VM and which differ.

  > ./scripts/cmp_state_dumps.sh
  diff:  0x636326f93a16be14b36b7e62c546370d81d285d1f5398e13d5348fa03a00d05.json
  match: 0x6902da2a7ef7f7ab2e984c0cdfa94c535dedd7cc081c91f04b9f87a9805411b.json
  diff:  0x75ae71b0aaba9454965d2077d53f056ffd426481bad709831e8d76d50f32dbe.json
  match: 0x7895207d7d46df77f5b0de6b647cd393b9fc7bb18c52b6333c6ea852cf767e.json
  match: 0x2335142d7b7938eeb4512fbf59be7ec2f2284e6533c14baf51460c8de427dc7.json
  match: 0x26f6d10918250f16cddaebb8b69c5cececf9387d4a152f4d9197e1c03c40626.json
  
  Finished comparison
  - Matching: 4
  - Diffing:  16

• delta_state_dumps.sh. It opens delta to review the differences between VM and Native with each transaction.

  > ./scripts/delta_state_dumps.sh