Add PowerShell as an optional default shell

CHANGELOG.md

@@ -1,5 +1,15 @@
 # Changelog
 
+## Unreleased
+
+### Added
+
+- Setup offers PowerShell 7 (`pwsh`) as an alternative default shell, installed
+  from Microsoft's GitHub release `.deb` after its release-asset SHA-256 is
+  verified. A managed `~/.config/powershell/profile.ps1` mirrors the bashrc
+  (starship, zoxide, mise, aliases) and a `~/.squarebox-use-pwsh` marker hands
+  interactive logins off to pwsh, matching the existing Zsh/Fish flow.
+
 ## v1.2.1 — 2026-07-31
 
 v1.2.0 was built as a draft Candidate but was never published after final

CLAUDE.md

@@ -91,7 +91,7 @@ Key rules:
 
 - Preserve old Selection on prompt cancellation; intentional empty selection is distinct.
 - Commit Selection/aliases from successful observed installs, not requested values.
-- Keep Bash, Zsh, and Fish derived configuration synchronized after section reruns.
+- Keep Bash, Zsh, Fish, and PowerShell derived configuration synchronized after section reruns.
 - Respect explicit user configuration during migrations (for example tmux mouse off).
 - Runtime APT must work with the read-only timezone mount and show actionable failures.
 - `sqrbx-learn` and its command logger are not shipped in the default v1.1 Box.
@@ -137,9 +137,10 @@ Managed-home volume copies. Bind mounts remain host-managed and are skipped;
 a symlink destination is rejected with a visible startup failure. Never follow
 a persistent-home symlink as root.
 
-Bash is default. Experimental Zsh/Fish are selected with markers in the Managed
-home and must initialize Starship, Zoxide, the `fzf`/`ff` command path, aliases,
-and mise. The packaged Ctrl+R/Ctrl+T/Alt+C/** bindings are a Bash-only contract.
+Bash is default. Experimental Zsh/Fish/PowerShell are selected with markers in
+the Managed home and must initialize Starship, Zoxide, the `fzf`/`ff` command
+path, aliases, and mise. The packaged Ctrl+R/Ctrl+T/Alt+C/** bindings are a
+Bash-only contract.
 
 ## Security posture
 

README.md

@@ -304,7 +304,7 @@ Installed during first-run setup. Choose any combination, or none:
 ### Shell (Experimental)
 
 By default, squarebox uses Bash. During first-run setup you can opt in to
-**Zsh** or **Fish** instead.
+**Zsh**, **Fish**, or **PowerShell** instead.
 
 **Zsh** installs:
 
@@ -324,14 +324,24 @@ autosuggestions and syntax highlighting built in. The generated
 AI/editor/TUI/SDK selections are translated from their bash files into
 `~/.config/fish/conf.d/squarebox-selections.fish` at setup time.
 
-> **Experimental:** the marker file `~/.squarebox-use-zsh` (or
-> `~/.squarebox-use-fish`) causes `~/.bashrc` to `exec` the chosen shell on
-> every interactive login, so the next shell start picks up the new shell.
-> Set `SQUAREBOX_NO_ZSH=1` or `SQUAREBOX_NO_FISH=1` to force bash for a single
-> session, or re-run `sqrbx-setup shell` to switch back permanently. Tooling
-> is primarily tested against bash, so a few edge cases may need polish —
-> please file an issue if you hit one. SDK shims are wired into all three
-> shells via `mise activate {bash,zsh,fish}`.
+**PowerShell** installs PowerShell 7 (`pwsh`) from Microsoft's official
+[GitHub release](https://github.com/PowerShell/PowerShell/releases) `.deb`
+(asset SHA-256 verified against the release metadata before install). The
+generated `~/.config/powershell/profile.ps1` mirrors the default bashrc in
+PowerShell-native syntax — starship, zoxide, and mise activate, plus the
+standard aliases as functions (PowerShell `Set-Alias` cannot attach
+arguments); AI/editor/TUI selections are translated from their bash files into
+`~/.config/powershell/squarebox-selections.ps1` at setup time.
+
+> **Experimental:** the marker file `~/.squarebox-use-zsh`,
+> `~/.squarebox-use-fish`, or `~/.squarebox-use-pwsh` causes `~/.bashrc` to
+> `exec` the chosen shell on every interactive login, so the next shell start
+> picks up the new shell. Set `SQUAREBOX_NO_ZSH=1`, `SQUAREBOX_NO_FISH=1`, or
+> `SQUAREBOX_NO_PWSH=1` to force bash for a single session, or re-run
+> `sqrbx-setup shell` to switch back permanently. Tooling is primarily tested
+> against bash, so a few edge cases may need polish — please file an issue if
+> you hit one. SDK shims are wired into all four shells via
+> `mise activate {bash,zsh,fish,powershell}`.
 
 ### SDKs
 

demo/setup-demo.sh

@@ -143,7 +143,7 @@ done <<< "$selected"
 echo
 section_header "Shell"
 selected=$(gum choose --header "Select the default shell:" \
-    "bash" "zsh (experimental)" "fish (experimental)") || true
+    "bash" "zsh (experimental)" "fish (experimental)" "powershell (experimental)") || true
 [ -n "$selected" ] && run_with_spinner "Configuring ${selected}..." 0.7
 
 echo

dotfiles/bashrc

@@ -79,4 +79,12 @@ if [ -f ~/.squarebox-use-fish ] && [ -z "${SQUAREBOX_IN_FISH:-}" ] && [ -z "${SQ
 	exec fish -l
 fi
 
+# Hand off to PowerShell if the user opted in via setup.sh (experimental).
+# SQUAREBOX_IN_PWSH guards against re-exec loops; SQUAREBOX_NO_PWSH lets
+# users force bash for one shell without removing the marker.
+if [ -f ~/.squarebox-use-pwsh ] && [ -z "${SQUAREBOX_IN_PWSH:-}" ] && [ -z "${SQUAREBOX_NO_PWSH:-}" ] && command -v pwsh >/dev/null 2>&1; then
+	export SQUAREBOX_IN_PWSH=1
+	exec pwsh -l
+fi
+
 [ -x /usr/local/lib/squarebox/motd.sh ] && /usr/local/lib/squarebox/motd.sh

scripts/e2e-test.sh

@@ -306,6 +306,11 @@ suite_setup_editors() {
 	else
 		tap_fail "3.12c no fish marker for bash selection"
 	fi
+	if [ ! -e ~/.squarebox-use-pwsh ]; then
+		tap_ok "3.12d no pwsh marker for bash selection"
+	else
+		tap_fail "3.12d no pwsh marker for bash selection"
+	fi
 
 	# 4.4 EDITOR set to first selected editor (micro)
 	run_test_grep "4.4 EDITOR set to micro" "micro" cat ~/.squarebox-editor-aliases

scripts/squarebox-entrypoint.sh

@@ -132,6 +132,10 @@ box_reconcile_needed() {
 		command -v fish >/dev/null 2>&1 || return 0
 		[ -f "$managed_home/.config/fish/config.fish" ] || return 0
 	fi
+	if selection_contains "$state/shell" pwsh; then
+		command -v pwsh >/dev/null 2>&1 || return 0
+		[ -f "$managed_home/.config/powershell/profile.ps1" ] || return 0
+	fi
 	return 1
 }
 

scripts/squarebox-setup.sh

@@ -36,7 +36,7 @@ usage() {
 	  tuis           TUI tools (lazygit, gh-dash, yazi, elio)
 	  multiplexers   Terminal multiplexers (tmux, zellij, herdr)
 	  sdks           SDKs (node, python, go, dotnet, rust)
-	  shell          Default shell (bash, zsh/fish — experimental)
+	  shell          Default shell (bash, zsh/fish/pwsh — experimental)
 
 	${BOLD}Examples:${RESET}
 	  sqrbx-setup ai editors       Re-run AI assistant and editor selection