What causes "'apt-get install -s' exited with code ${code}:\n${stderr || stdout}" in microsoft/playwright?

Run `sudo apt-get update` to refresh package lists, then re-run the Playwright dependency install.

microsoft/playwright · error · Error

'apt-get install -s' exited with code ${code}:\n${stderr ||

Error message

'apt-get install -s' exited with code ${code}:\n${stderr || stdout}

What it means

Thrown by reportMissingDependenciesLinux when `apt-get install -s` launches but exits with a non-zero code. The simulation (dry-run) failed, so Playwright cannot determine which packages are missing; stderr or stdout is included to show apt-get's complaint.

Source

Thrown at packages/playwright-core/src/server/registry/dependencies.ts:134

  const { command, args, elevatedPermissions } = await transformCommandsForRoot(commands);
  if (elevatedPermissions)
    console.log('Switching to root user to install dependencies...'); // eslint-disable-line no-console
  const child = childProcess.spawn(command, args, { stdio: 'inherit' });
  await new Promise<void>((resolve, reject) => {
    child.on('exit', (code: number) => code === 0 ? resolve() : reject(new Error(`Installation process exited with code: ${code}`)));
    child.on('error', reject);
  });
}

async function reportMissingDependenciesLinux(packages: string[]) {
  // `apt-get install -s` simulates the install: it does not need root and does not
  // modify the system. Stdout includes one `Inst <package> ...` line per package
  // that would be installed (i.e. that is currently missing).
  const { code, stdout, stderr, error } = await spawnAsync('apt-get', ['install', '-s', '--no-install-recommends', ...packages], {});
  if (error)
    throw new Error(`Failed to run 'apt-get install -s' to simulate dependency install: ${error.message}`);
  if (code !== 0)
    throw new Error(`'apt-get install -s' exited with code ${code}:\n${stderr || stdout}`);
  const missingPackages: string[] = [];
  for (const line of stdout.split('\n')) {
    const match = /^Inst (\S+) /.exec(line);
    if (match)
      missingPackages.push(match[1]);
  }
  if (!missingPackages.length) {
    console.log('All system dependencies are installed.'); // eslint-disable-line no-console
    return;
  }
  // eslint-disable-next-line no-console
  console.log(`Missing system dependencies (${missingPackages.length}):\n${missingPackages.sort().map(p => `  ${p}`).join('\n')}`);
  process.exitCode = 1;
}

export async function validateDependenciesWindows(sdkLanguage: string, windowsExeAndDllDirectories: string[]) {
  const directoryPaths = windowsExeAndDllDirectories;
  const lddPaths: string[] = [];

View on GitHub (pinned to c8fc3bf8d3)

Solutions

Run `sudo apt-get update` to refresh package lists, then re-run the Playwright dependency install.
Inspect the captured stderr/stdout in the error to find which package or repository is failing and fix the apt sources.
If on a derivative distro, ensure its repositories actually carry the packages Playwright needs, or switch to the official Playwright image.

Example fix

sudo apt-get update
sudo npx playwright install-deps
# or rebuild image layer that caches an out-of-date index

Defensive patterns

Strategy: validation

Validate before calling

import { execSync } from 'node:child_process';
try { execSync('apt-get install -s --no-install-recommends <pkg>', { stdio: 'pipe' }); }
catch (e) { console.warn('apt cache may be stale: run apt-get update'); }

Try / catch

try {
  await installDeps();
} catch (e) {
  if (/apt-get install -s.*exited with code/.test(e.message)) {
    await run('sudo', ['apt-get', 'update']);
    await installDeps(); // one retry after refreshing the index
  } else throw e;
}

Prevention

Run apt-get update in CI before installing Playwright deps.
Rebuild Docker layers that cache stale apt indexes.
Ensure apt sources/mirrors are reachable behind proxies.

When it happens

Trigger: apt-get is present but the simulation fails: package lists are out of date (run apt-get update needed), a referenced package is unavailable in configured repositories, repositories are misconfigured, or dpkg is in a broken state.

Common situations: Stale apt cache in a Docker image built from a cached layer; disabled/unreachable apt mirrors behind a corporate proxy; a partially upgraded system with held/broken packages; an older image whose package names changed.

Related errors

AI-assisted analysis of microsoft/playwright@c8fc3bf8d3 (2026-08-12). Data as JSON: /api/errors/78f96facb4f7ea16. Report an issue: GitHub.