Parallel work with git worktrees instead of stash-and-switch

Goal

Work on two or more branches at the same time, each in its own directory with its own build state, without cloning again and without repeatedly stashing and switching.

Prerequisites

A git repository (its checkout is the "main worktree"). Disk space for additional checkouts. Tooling that does not hard-code a single repository path: editor projects, virtual environments, build directories.

Steps

1. Create a worktree for an existing branch: git worktree add ../repo-review feature/x. For a new branch: git worktree add -b fix/login ../repo-fix. The documentation notes that git worktree add <path> alone creates a branch named after the last path component, and that -d creates a throwaway checkout with a detached HEAD.
2. Work in the new directory as in any checkout. The documentation describes the new tree as a "linked worktree" that shares everything with the repository except per-worktree files such as HEAD and the index; refs under refs/ are shared, pseudo-refs such as HEAD are per worktree.
3. Set up whatever the tooling keeps outside git: dependency installs, .env copies, build directories. Untracked files are not shared between worktrees.
4. List what exists with git worktree list (--porcelain for scripts). git refuses to create a worktree for a branch that is already checked out elsewhere unless --force is given, so use one branch per worktree.
5. When finished: git worktree remove ../repo-fix (it refuses an unclean tree unless forced), then delete the branch if merged. If a directory was deleted by hand, git worktree prune removes the stale administrative files; git worktree repair reconnects trees that were moved.
6. For settings that must differ per worktree, enable extensions.worktreeConfig and use git config --worktree, as the documentation describes.

Expected result

Several directories, each on its own branch, sharing one object store and one set of remotes; switching context is cd, and a long test run in one worktree does not block edits in another.

Limits and test basis

Semantics follow the cited git-worktree documentation. Worktrees containing submodules cannot be moved with git worktree move. Because everything except per-worktree files is shared, hooks and repository configuration apply to all worktrees. Tools that cache by path (language servers, container mounts, IDE indexes) may need separate configuration, and disk use grows with each worktree. No performance measurement is claimed.