What causes "Must have yarn or npm installed to run build." in Budibase/budibase?

Install Node.js (which bundles npm) from nodejs.org or via nvm, then verify `npm --version`

Must have yarn or npm installed to run build.

Error message

Must have yarn or npm installed to run build.

What it means

This is the terminal fallback in runPkgCommand: when the project provides no packageManager/lockfile signal (resolvePackageManager returns "auto"), the CLI tries npm then yarn; if neither binary is installed it cannot run any package script and throws this error.

Source

Thrown at packages/cli/src/exec.ts:113

      command === "install" ? `npm ${command}` : `npm run ${command}`
    await exec(npmCmd, dir)
    return
  }

  // Default to npm when the project has no lockfile/packageManager signal.
  if (npm) {
    const npmCmd =
      command === "install" ? `npm ${command}` : `npm run ${command}`
    await exec(npmCmd, dir)
    return
  }

  if (yarn) {
    await exec(`yarn ${command} --ignore-engines`, dir)
    return
  }

  throw new Error("Must have yarn or npm installed to run build.")
}

View on GitHub (pinned to a81a902e9a)

Solutions

Install Node.js (which bundles npm) from nodejs.org or via nvm, then verify `npm --version`
Fix PATH in the execution environment (CI step, sudo secure_path, shell profile) so node/npm are found
Add a lockfile or packageManager field so a specific manager is detected, and install that manager
If using nvm, ensure `nvm use` runs in non-interactive shells (e.g. CI) before invoking budi

Example fix

// CI before
- run: budi plugins build   # no node/npm in image
// after
- uses: actions/setup-node@v4
  with: { node-version: 20 }
- run: budi plugins build

Defensive patterns

Strategy: validation

Validate before calling

const { execSync } = require("child_process")
function assertAnyPkgManager() {
  const ok = (cmd) => { try { execSync(cmd, { stdio: "ignore" }); return true } catch { return false } }
  if (!ok("npm --version") && !ok("yarn --version")) {
    throw new Error("Install Node.js (npm) or yarn before running budi plugin commands")
  }
}

Try / catch

try {
  await runPkgCommand("build", dir)
} catch (err) {
  if ((err as Error).message === "Must have yarn or npm installed to run build.") {
    console.error("No package manager on PATH; install Node.js first")
  }
  throw err
}

Prevention

Install Node.js before using the budi CLI
If using nvm, ensure it's loaded in non-interactive shells (CI, scripts)
Check `which node`/`which npm` when running under sudo or systemd
Add a tooling preflight step in CI images

When it happens

Trigger: Running budi plugin init/build/watch or the Svelte 5 migration in a plugin directory with no packageManager field and no lockfile, on a machine where both `npm --version` and `yarn --version` fail (Node.js not installed, or PATH not including the node bin directory).

Common situations: Fresh machines/containers without Node.js; running the CLI under sudo or systemd with a stripped PATH; broken nvm setup where the default node version isn't loaded in non-interactive shells.

Related errors

AI-assisted analysis of Budibase/budibase@a81a902e9a (2026-08-29). Data as JSON: /api/errors/afde318bd11ffe4d. Report an issue: GitHub.