diff --git a/.chezmoiscripts/run_after_99-next-step.sh b/.chezmoiscripts/run_after_99-next-step.sh
new file mode 100755
index 0000000..bab0e29
--- /dev/null
+++ b/.chezmoiscripts/run_after_99-next-step.sh
@@ -0,0 +1,27 @@
+#!/bin/sh
+# Say what to run next, using a path that actually works right now.
+#
+# `dotup` lands in ~/.local/bin, and Ubuntu's stock ~/.profile does add that to
+# PATH -- but behind `[ -d "$HOME/.local/bin" ]`, evaluated once, at login. On
+# a fresh box the directory does not exist when you log in, so it is not on
+# PATH; this apply then creates it; and the shell you are sitting in never
+# re-reads .profile. The result is that `dotup` is "command not found" in
+# exactly the session that just installed it, and works fine in the next one.
+#
+# That cannot be fixed from inside a child process -- nothing here can alter
+# the PATH of the shell that invoked it. What it can do is stop the user
+# guessing: print the absolute path, which always works, and say why the bare
+# name does not yet.
+#
+# Silent once PATH is sorted out, so a routine `chezmoi update` says nothing.
+set -eu
+
+command -v dotup >/dev/null 2>&1 && exit 0
+[ -x "$HOME/.local/bin/dotup" ] || exit 0
+
+printf '\n' >&2
+printf 'Next:  ~/.local/bin/dotup\n' >&2
+printf '\n' >&2
+printf 'Type the path in full. `dotup` on its own will not be found until you\n' >&2
+printf 'open a new shell -- ~/.profile only adds ~/.local/bin to PATH if the\n' >&2
+printf 'directory already existed when you logged in, and it did not.\n' >&2
diff --git a/.chezmoiscripts/run_before_00-require-git.sh b/.chezmoiscripts/run_before_00-require-git.sh
new file mode 100755
index 0000000..a4f44ea
--- /dev/null
+++ b/.chezmoiscripts/run_before_00-require-git.sh
@@ -0,0 +1,64 @@
+#!/bin/sh
+# git has to exist before chezmoi fetches the six git-repo externals.
+#
+# The documented first command is
+#
+#     sh -c "$(curl -fsLS get.chezmoi.io)" -- init --apply <url>
+#
+# and on a stock box it used to fail here:
+#
+#     chezmoi: .config/tmux/plugins/tpm: exec: "git": executable file not found
+#
+# chezmoi itself is a static download and installs fine. git is a different
+# matter: Ubuntu Server cloud images, the Ubuntu docker image and WSL Ubuntu all
+# ship curl and none of them ship git. So the front door of the whole system
+# did not open on the most ordinary kind of fresh machine there is.
+#
+# `run_before_` is the fix rather than a README note, because chezmoi runs these
+# before every other target -- externals included. Verified, not assumed: a
+# probe script printed "git ABSENT here" and the external failed immediately
+# after, in that order.
+#
+# This exits in microseconds on every machine that already has git, which after
+# the first apply is all of them.
+set -eu
+
+command -v git >/dev/null 2>&1 && exit 0
+
+printf 'chezmoi: git is required for the shell externals and is not installed.\n' >&2
+
+# Root needs no sudo; a non-root user without sudo cannot do this at all, and
+# should be told rather than shown a package manager error.
+if [ "$(id -u)" -eq 0 ]; then
+	SUDO=
+elif command -v sudo >/dev/null 2>&1; then
+	SUDO=sudo
+else
+	printf 'chezmoi: cannot install it -- not root and no sudo. Install git and re-run:\n' >&2
+	printf 'chezmoi:   chezmoi init --apply <url>\n' >&2
+	exit 1
+fi
+
+printf 'chezmoi: installing git...\n' >&2
+if   command -v apt-get >/dev/null 2>&1; then
+	${SUDO} env DEBIAN_FRONTEND=noninteractive apt-get update -qq || :
+	${SUDO} env DEBIAN_FRONTEND=noninteractive apt-get install -y -qq git
+elif command -v dnf     >/dev/null 2>&1; then ${SUDO} dnf install -y git
+elif command -v yum     >/dev/null 2>&1; then ${SUDO} yum install -y git
+elif command -v pacman  >/dev/null 2>&1; then ${SUDO} pacman -Sy --noconfirm git
+elif command -v zypper  >/dev/null 2>&1; then ${SUDO} zypper --non-interactive install git
+elif command -v apk     >/dev/null 2>&1; then ${SUDO} apk add --no-cache git
+elif command -v brew    >/dev/null 2>&1; then brew install git
+elif [ "$(uname -s)" = Darwin ]; then
+	# On macOS `git` is a stub that triggers the Command Line Tools installer,
+	# which is a GUI dialog -- there is nothing useful to do unattended.
+	printf 'chezmoi: run `xcode-select --install`, then re-run chezmoi init --apply.\n' >&2
+	exit 1
+else
+	printf 'chezmoi: no package manager I recognise. Install git and re-run.\n' >&2
+	exit 1
+fi
+
+command -v git >/dev/null 2>&1 \
+	|| { printf 'chezmoi: git still not on PATH after installing it.\n' >&2; exit 1; }
+printf 'chezmoi: git %s installed.\n' "$(git --version | awk '{print $3}')" >&2