The error described below is produced when attempting to compile the node upgraded to v3. The Cargo.toml files indeed specify the js feature; the issue occurs when compiling packages within Cargo.lock, which include the getrandom package. As getrandom is the direct dependency of those packages, I am not sure how to specify js feature for them as well. Please let me know what can be done to resolve this issue.

Compiling getrandom v0.2.6 error: the wasm32-unknown-unknown target is not supported by default, you may need to enable the "js" feature. For more information see: https://docs.rs/getrandom/#webassembly-support --> /Users/raid/.cargo/registry/src/github.com-1ecc6299db9ec823/getrandom-0.2.6/src/lib.rs:235:9 | 235 | / compile_error!("the wasm32-unknown-unknown target is not supported by
236 | | default, you may need to enable the "js" feature.
237 | | For more information see:
238 | | https://docs.rs/getrandom/#webassembly-support"); | |________________________________________________________________________^

  • I’m voting to close this question because no more active.
    – AurevoirXavier
    Aug 29, 2022 at 1:49

1 Answer 1


I would assume that this error comes from the new try-runtime feature, which wasn't correctly added to the substrate-node-template.

At least when I run cargo check --all-features on a fresh substrate-node-template then it returns cannot find trait TryRuntime in crate frame_try_runtime.

I fixed this by going into runtime/Cargo.toml and adding the following. This would exclude the standard library to properly work with WASM.

std = [

Please double check if you have the following package in your runtime/Cargo.toml with default-features = false:

frame-try-runtime = { ..., default-features = false, git = "https://github.com/paritytech/substrate.git", ... }

Make sure that you don't have the try-runtime-cli dependency in runtime/Cargo.toml.

If this doesn't help, then please try to give additional information about how to reproduce the error. Which substrate-node-template version did you run?

  • I created a pull request for this here.
    – Chralt
    May 24, 2022 at 20:03
  • Also look at this
    – Chralt
    May 24, 2022 at 20:47

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