DioxusLabs/dioxus · error · anyhow::Error

esbuild failed: {stderr}

Error message

esbuild failed: {stderr}

What it means

For JS/TS assets, dx shells out to the esbuild binary as a subprocess. If the process runs but exits non-zero, its captured stderr is re-raised as 'esbuild failed: {stderr}'. (A failure to spawn the binary would produce 'Failed to run esbuild' instead, so this error means esbuild itself rejected the input.)

Source

Thrown at packages/cli/src/opt/js.rs:85

    }

    if lexer::js_is_module(js_options, source) {
        cmd.arg("--bundle");
        cmd.arg("--format=esm");
        // Don't try to resolve URL-based imports at build time — let the
        // browser fetch them at runtime. Without these externals, esbuild
        // errors out on patterns like `import x from "https://cdn/lib.js"`.
        cmd.arg("--external:https://*");
        cmd.arg("--external:http://*");
    }

    tracing::debug!("Running esbuild: {:?}", cmd);

    let output = cmd.output().context("Failed to run esbuild")?;

    if !output.status.success() {
        let stderr = String::from_utf8_lossy(&output.stderr);
        anyhow::bail!("esbuild failed: {stderr}");
    }

    Ok(())
}

pub(crate) fn hash_js(
    _js_options: &JsAssetOptions,
    source: &Path,
    hasher: &mut impl std::hash::Hasher,
) -> anyhow::Result<()> {
    hash_file_contents(source, hasher)
}

pub use lexer::*;
mod lexer {
    //! Detect whether a JavaScript source file uses ES module syntax.
    //!
    //! This is a token-level scanner inspired by Guy Bedford's `es-module-lexer`

View on GitHub (pinned to 393d190a80)

Solutions

1. Read the esbuild stderr embedded in the message — it names the file, line, and problem
2. Reproduce outside dx by running esbuild on the same file with the same flags to iterate quickly
3. Fix the import/parse error, or mark the problematic dependency external
4. If you suspect a version mismatch, install esbuild 0.27.3 on PATH and run it manually to confirm behavior

# Reproduce esbuild's verdict on the asset before dx build
esbuild --bundle assets/app.js --outfile=/dev/null --external:https://* --external:http://*

When it happens

Trigger: esbuild rejecting a JS/TS asset: unresolved relative imports, syntax it cannot parse, or remote http(s) imports when the external flags do not cover the pattern; the subprocess's stderr is passed through verbatim.

Common situations: Importing CDN URLs with schemes not covered by --external:https://* / --external:http://*; TS syntax unsupported by the pinned esbuild 0.27.3; broken relative paths after moving asset files.

Related errors

• esbuild not found on PATH and downloads are disabled
• No esbuild binary available for this platform
• esbuild binary not found in archive (expected one of {}). Fo
• Failed to run linker
• Failed to execute rustc command

AI-assisted analysis of DioxusLabs/dioxus@393d190a80 (2026-08-16). Data as JSON: /api/errors/036f2bb05aef5988. Report an issue: GitHub.