diff --git a/.scripts/tmux-powerline.sh b/.scripts/tmux-powerline.sh
new file mode 100755
index 0000000..5a1d76d
--- /dev/null
+++ b/.scripts/tmux-powerline.sh
@@ -0,0 +1,28 @@
+#!/bin/sh
+# Load powerline's tmux bindings, if powerline is installed at all.
+#
+# tmux.conf used to source
+#   /usr/lib/python3.11/site-packages/powerline/bindings/tmux/powerline.conf
+# which pins a Python minor version into a path. That breaks on every Python
+# upgrade and had already broken everywhere: beastix is on 3.14, and shron had
+# the line commented out entirely until a checkout replaced its tmux.conf with
+# a copy carrying the dead path. Every tmux session there then opened with
+#   No such file or directory: /usr/lib/python3.11/...
+#
+# Resolving the path from the module itself keeps it correct across upgrades,
+# and every step is allowed to fail quietly so a machine without powerline -
+# the Mac has neither it nor tmux - simply gets nothing.
+set -u
+
+command -v powerline-daemon >/dev/null 2>&1 || exit 0
+command -v python3 >/dev/null 2>&1 || exit 0
+
+powerline-daemon -q 2>/dev/null || exit 0
+
+dir=$(python3 -c 'import os, powerline; print(os.path.dirname(powerline.__file__))' 2>/dev/null) || exit 0
+[ -n "$dir" ] || exit 0
+
+conf="$dir/bindings/tmux/powerline.conf"
+[ -r "$conf" ] || exit 0
+
+tmux source-file "$conf"
diff --git a/tmux.conf b/tmux.conf
index 701c08c..1f3d659 100644
--- a/tmux.conf
+++ b/tmux.conf
@@ -143,8 +143,10 @@ bind S split-window -v
 #https://github.com/thewtex/tmux-mem-cpu-load
 #set -g status-interval 2
 #set -g status-right "#(tmux-mem-cpu-load 2) #H"
-run-shell "powerline-daemon -q"
-source '/usr/lib/python3.11/site-packages/powerline/bindings/tmux/powerline.conf'
+# powerline, resolved at runtime rather than pinned to a Python version.
+# See .scripts/tmux-powerline.sh - the old hardcoded path was already wrong on
+# every machine and made tmux print an error on every start.
+run-shell "$HOME/.scripts/tmux-powerline.sh"
 
 # disable mouse control by default - change 'off' to 'on' to enable by default.
 setw -g mouse off