9 releases (4 breaking)

0.4.0 Jul 31, 2018
0.3.0 Jul 4, 2018
0.2.1 Jul 2, 2018
0.2.0 Apr 25, 2018
0.0.0 Jan 26, 2018

#2 in WebAssembly

Download history 2274/week @ 2018-08-05 2624/week @ 2018-08-12 2176/week @ 2018-08-19 1224/week @ 2018-08-26 932/week @ 2018-09-02 1090/week @ 2018-09-09 1206/week @ 2018-09-16 1270/week @ 2018-09-23 1208/week @ 2018-09-30 950/week @ 2018-10-07 1008/week @ 2018-10-14 927/week @ 2018-10-21 823/week @ 2018-10-28

8,054 downloads per month
Used in 2 crates (1 directly)



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WASM interpreter (previously lived in parity-wasm)

Primary purpose of wasmi is to be used with parity (ethereum-like contracts in wasm) and with Polkadot. However, wasmi is designed to be as flexible as possible and might be suited well for other purposes.

At the moment, the API is rather low-level (especially, in the part related to host functions). But some high-level API is on the roadmap.


wasmi is primarily distributed under the terms of both the MIT license and the Apache License (Version 2.0), at your choice.

See LICENSE-APACHE, and LICENSE-MIT for details.

Build & Test

As wasmi contains a git submodule, you need to use --recursive for cloning or to checkout the submodule explicitly, otherwise the testing would fail.

git clone https://github.com/paritytech/wasmi.git --recursive
cd wasmi
cargo build
cargo test


Unless you explicitly state otherwise, any contribution intentionally submitted for inclusion in wasmi by you, as defined in the Apache-2.0 license, shall be dual licensed as above, without any additional terms or conditions.