Ancient included pnpm 8.15.6 fails out of the box on modern pnpm-workspace.yaml without packages #2149

Companion StackBlitz issue to pnpm issues pnpm/pnpm#14018, pnpm/pnpm#14030 and pnpm/pnpm#15649

Describe the bug

StackBlitz WebContainers include the very old pnpm version 8.15.6, which fails on a valid modern pnpm-workspace.yaml without a packages field with the error message  ERR_PNPM_INVALID_WORKSPACE_CONFIGURATION  packages field missing or empty

The packages field has been optional since pnpm 10.5.0 (released in Feb 2025), so repositories using modern pnpm configuration can fail automatically when opened in StackBlitz.

Link to the blitz that caused the error

https://stackblitz.com/edit/github-fuwsaec6?file=pnpm-workspace.yaml

Steps to reproduce

1. Visit the reproduction URL above
2. Observe that pnpm (default installed version on StackBlitz: 8.15.6) fails immediately with the following error message 💥

   ~/projects/github-fuwsaec6
   ❯ pnpm install
    ERR_PNPM_INVALID_WORKSPACE_CONFIGURATION  packages field missing or empty

3. Check the included pnpm version and observe that StackBlitz is using pnpm 8.15.6

   ~/projects/github-fuwsaec6 1s
   ❯ pnpm --version
   8.15.6

Attempts to upgrade this version using commands from the pnpm docs fail:

1. Attempt to install pnpm by following the Using npm section on the Installation docs page, and observe that the installer fails because tar is unavailable 💥

   ~/projects/github-fuwsaec6
   ❯ npx get-pnpm
   Need to install the following packages:
   get-pnpm@0.0.3
   Ok to proceed? (y) y
   
   ==> Downloading pnpm 11.22.0
   This installer needs the `tar` command, which was not found on your PATH.

2. Attempt to install pnpm 11 directly using npm, and observe that npm cannot write to its default global installation directory /usr/local/lib/node_modules 💥

   ~/projects/github-fuwsaec6 12s
   ❯ npm install --global pnpm@11
   npm error code EACCES
   npm error syscall mkdir
   npm error path /usr/local/lib/node_modules/pnpm
   npm error errno -13
   npm error Error {
   npm error   code: 'EACCES',
   npm error   errno: -13,
   npm error   path: '/usr/local/lib/node_modules/pnpm',
   npm error   syscall: 'mkdir',
   npm error   message: "EACCES: permission denied, mkdir '/usr/local/lib/node_modules/pnpm'",
   npm error   stack: "Error: EACCES: permission denied, mkdir '/usr/local/lib/node_modules/pnpm'"
   npm error }
   npm error
   npm error The operation was rejected by your operating system.
   npm error It is likely you do not have the permissions to access this file as the current user
   npm error
   npm error If you believe this might be a permissions issue, please double-check the
   npm error permissions of the file and its containing directories, or try running
   npm error the command again as root/Administrator.
   npm error A complete log of this run can be found in: /home/.npm/_logs/2026-08-19T16_31_38_032Z-debug-0.log

Installing a usable version of pnpm 10 (pnpm 11 and pnpm 12 do not run on StackBlitz) requires these workarounds:

1. Install pnpm 10 using npm, working around the read-only global installation directory by installing into the home directory

   ~/projects/github-fuwsaec6 1s
   ❯ npm install --global --prefix "$HOME/.local" pnpm@10
   
   added 1 package in 2s
   
   1 package is looking for funding
     run `npm fund` for details

2. Attempt to run the installed pnpm 10, and observe pnpm can print its version but pnpm install fails because the project .npmrc does not exist (also reported as issue pnpm/pnpm#14030) 💥

   ~/projects/github-fuwsaec6
   ❯ "$HOME/.local/bin/pnpm" --version
   10.34.5
   
   ~/projects/github-fuwsaec6
   ❯ "$HOME/.local/bin/pnpm" install
    ENOENT  ENOENT: no such file or directory, open '/home/projects/github-fuwsaec6/.npmrc'

3. Create the missing optional project .npmrc, retry the install, and observe that the failure now originates from /home/.pnpm/.pnpmfile.cjs 💥

   ~/projects/github-fuwsaec6
   ❯ touch .npmrc
   
   ~/projects/github-fuwsaec6
   ❯ "$HOME/.local/bin/pnpm" install
    WARN  Ignoring broken lockfile at /home/projects/github-fuwsaec6/node_modules/.pnpm: ENOENT: no such file or directory, open '/home/projects/github-fuwsaec6/node_modules/.pnpm/lock.yaml'
    ERR_INVALID_ARG_TYPE  The "path" argument must be of type string or an instance of Buffer or URL. Received undefined
   
   This error happened while installing a direct dependency of /home/projects/github-fuwsaec6
   
   pnpm [ERR_INVALID_ARG_TYPE]: The "path" argument must be of type string or an instance of Buffer or URL. Received undefined
       at Object.mkdirSync (https://githubfuwsaec6-0c1d-unyik1or.w-credentialless-staticblitz.com/builtins.2896b7f3.js:31:16060)
       at eval (/home/.pnpm/.pnpmfile.cjs:1:4125)
       at async fetcher (/home/.local/lib/node_modules/pnpm/dist/pnpm.cjs:116247:16)
       at async run (/home/.local/lib/node_modules/pnpm/dist/pnpm.cjs:115579:23)

4. Inspect StackBlitz's global pnpm configuration and observe that it configures /home/.pnpm/.pnpmfile.cjs

   ~/projects/github-fuwsaec6
   ❯ cat /home/.npmrc
   update-notifier=false
   
   # pnpm options
   ignore-dep-scripts=true
   prefer-symlinked-executables=true
   verify-store-integrity=false
   global-pnpmfile=~/.pnpm/.pnpmfile.cjs

5. Retry with --ignore-pnpmfile to bypass StackBlitz's global .pnpmfile.cjs, and observe that the install succeeds

   ~/projects/github-fuwsaec6
   ❯ "$HOME/.local/bin/pnpm" --ignore-pnpmfile install
    WARN  Ignoring broken lockfile at /home/projects/github-fuwsaec6/node_modules/.pnpm: ENOENT: no such file or directory, open '/home/projects/github-fuwsaec6/node_modules/.pnpm/lock.yaml'
   Lockfile is up to date, resolution step is skipped
   Packages: +369
   ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
   Progress: resolved 369, reused 0, downloaded 369, added 369, done
   
   dependencies:
   + ansis 4.3.1
   + randomcolor 0.6.2
   
   devDependencies:
   + @types/node 26.1.2
   + @types/randomcolor 0.5.9
   + @types/styled-components 5.1.36
   + eslint 10.8.1
   + eslint-config-upleveled 10.0.2
   + prettier 3.9.6
   + typescript 6.0.3
   
   Done in 7.8s using pnpm v10.34.5

Expected behavior

StackBlitz includes a supported pnpm version that supports modern pnpm-workspace.yaml configuration, including files without a packages field, so pnpm projects install out of the box without StackBlitz-specific workarounds

Parity with Local

• I have run the project in my local machine and I could not reproduce the issue.

Screenshots

(included inline above)

Platform

• OS: macOS Tahoe 26.5.2 (25F84)
• Browser: Chrome
• Version: 151.0.7922.138 (macOS)

Additional context

Related issues:

• Jan 2025: stackblitz/core issue from @Mister-Hope requesting pnpm 9/10 support support pnpm v9/v10 core#3237

cc @SamVerschueren if this should be reported some other way or in stackblitz/core, let me know