mise/Shim

• What Is a Shim in mise? Shims | mise-en-place

  • Overview

    • A shim is a tiny executable that masquerades as the tool you want to run (e.g. node, prettier). Each shim is a symlink to the mise binary that intercepts your shell call, figures out which version of the tool should run, loads the declared mise/Environment changes, and then delegates execution. See Shims in the mise docs.

  • Context

    • mise/activate rewrites Shell/PATH on every prompt; this is great for interactive shells but unavailable to non-interactive environments like CI, IDEs, or scripts. Shims offer a static directory of stand-ins that works even when the shell cannot evaluate mise activate. See Shims vs PATH activation.
    • By default, shims live in ~/.local/share/mise/shims. Adding this directory to PATH (or using mise activate --shims) makes every installed tool appear globally available. See mise activate --shims.

  • Key Principles

    • One shim per binary – every bin file provided by a tool gets its own shim at install time.
    • Environment on demand – mise/Config/mise.toml/env load only when a shim runs; they are not present for unrelated commands. See Shims: Environment.
    • Reshim after changes – installing via managers that mise cannot detect (e.g. yarn, pnpm) may require a manual mise reshim to regenerate the shim set. See mise reshim command.

  • Mechanism

    • Creation – mise install (or any tool install) drops binaries, then writes matching shims; mise reshim can recreate them later. See Shims: Creation.
    • Resolution flow
      • 1. You run node.
      • 2. Shell finds ~/.local/share/mise/shims/node.
      • 3. Shim runs mise, which selects the correct node version for the current directory and executes it.
      • 4. Subsequent child processes inherit the full PATH so they don't trigger mise again.
    • Symlink anatomy
      • sh

        ls -l ~/.local/share/mise/shims/node
        # ~/.local/share/mise/shims/node -> ~/.local/bin/mise

  • Examples

    • Listing versions via a shim path
      • sh

        ~/.local/share/mise/shims/node -v   # v20.0.0
        ~/.local/share/mise/shims/prettier -v  # 3.1.0

    • Force-update shims after a global npm i -g
      • sh

        mise reshim           # recreates all shims

      • See mise reshim documentation.

  • Misconceptions

    • "Shims give me every mise feature." Not quite: hooks, some env-vars, and which accuracy are limited under shims. See Shims: Limitations.
    • "which node shows the real binary." It shows the shim; use mise which node to see the resolved path. See FAQ: which node.
    • "Shims always outperform mise activate." Both pay a small cost—activate on each prompt, shim on each invocation; impact depends on workflow. See Shims: Performance.

  • Related

    • Shims vs PATH activation – trade-offs and limitations
    • mise reshim command – manual shim regeneration
    • mise activate --shims – add shim dir to PATH automatically