--- name: pnpm-global-virtual-store description: Global virtual store for shared node_modules across checkouts, git-worktree multi-agent setups, and isolated global packages --- # Global Virtual Store, Git Worktrees & Global Packages ## Global virtual store By default each project has its own `node_modules/.pnpm` virtual store containing hard links to the content-addressable store. With the **global virtual store** enabled, pnpm keeps one shared virtual store at `/links/` (find it via `pnpm store path`), and each project's `node_modules` contains only **symlinks** into it. ```yaml title="pnpm-workspace.yaml" enableGlobalVirtualStore: true ``` ``` # Default (per-project .pnpm with hard links) project-a/node_modules/lodash -> .pnpm/lodash@4.17.21/node_modules/lodash # Global virtual store (symlink to shared location) project-a/node_modules/lodash -> /links/@/lodash/4.17.21//node_modules/lodash project-b/node_modules/lodash -> /links/@/lodash/4.17.21//node_modules/lodash # same target ``` - **Package identity = hash of the dependency graph.** Two projects with the same `lodash@4.17.21` and the same transitive tree point at the exact same directory (NixOS-style). Different peers ⇒ separate entries. - **Near-zero per-project cost** and **instant installs** once a version is in the store. - In **pnpm v11** it is the default for `pnpm dlx`/`pnx` and global installs; for **project** installs it is still **opt-in/experimental**. ### Limitations - **CI:** auto-disabled (no warm cache to benefit from). - **Trust:** the store is shared writable state — only for mutually trusting projects/users/jobs; protect the path with filesystem permissions. - **ESM hoisting:** relies on `NODE_PATH`, which Node ignores for ESM imports. If ESM deps import undeclared packages, resolution fails. Fix with `packageExtensions` or the `@pnpm/plugin-esm-node-path` config dependency. ## Git worktrees for multi-agent development Git worktrees let you check out many branches simultaneously, each in its own directory, sharing one `.git` object store. Combined with the global virtual store, every worktree gets a fully functional `node_modules` that is almost free on disk — ideal for running multiple AI agents in parallel. ```sh # Bare repo as the hub, one worktree per branch/agent git clone --bare https://github.com/your-org/your-monorepo.git your-monorepo cd your-monorepo git worktree add ./main main git worktree add ./feature-auth feat/auth git worktree add ./fix-api fix/api-error ``` ```yaml title="pnpm-workspace.yaml" packages: - 'packages/*' enableGlobalVirtualStore: true ``` ```sh cd main && pnpm install # first install fills the global store cd ../feature-auth && pnpm install # subsequent worktrees: nearly instant, just symlinks ``` Each worktree has its own `node_modules` tree (so agents can install different versions on different branches without conflict), but all package contents come from the one shared store. Remove a worktree with `git worktree remove ./feature-auth`. > The pnpm repo itself uses this setup and ships helper scripts (`pnpm worktree:new `). Assumes all worktrees/agents share the same trust boundary. ## Global packages (v11 isolated installs) `pnpm add -g` was redesigned in v11 for isolation. Each globally installed package (or group) gets its own install directory with its own `package.json`, `node_modules/`, and lockfile, so global tools can't break each other via peer/hoisting conflicts. Installs are stored at `{pnpmHomeDir}/global/v11/{hash}/` and share the global virtual store. ```sh pnpm add -g typescript prettier # space-separated = separate isolated installs each pnpm add -g eslint,prettier # comma-separated = ONE shared install group pnpm remove -g eslint # removes only eslint's group pnpm add -g --allow-build=esbuild esbuild # pre-approve build scripts pnpm list -g # always works at depth 0 pnpm bin -g # global bin dir = $PNPM_HOME/bin ``` - `pnpm install -g` (no args) is **not** supported — use `pnpm add -g `. - Binaries live in `$PNPM_HOME/bin` (not `$PNPM_HOME` directly). Run `pnpm setup` after upgrading to put it on PATH. - Register a local package's bins globally with `pnpm add -g .` (replaces `pnpm link --global`). - `pnpm list -g --depth=` (n>0) only works for a single install group. ## Key Points - `enableGlobalVirtualStore: true` ⇒ `node_modules` is symlinks into one shared, hash-addressed store. - Best for many checkouts of the same repo (git worktrees, parallel agents); auto-disabled in CI. - Watch out for ESM packages importing undeclared deps (NODE_PATH limitation). - v11 global installs are isolated per package; comma-list to share a group; bins live in `$PNPM_HOME/bin`.