Real bug behind 0.27.0-fork.5 and fork.7 shipping stale linux binaries.
Docker compose interpolates \${VAR} (and \$VAR) at YAML parse time
against the host shell — including inside `command:` blocks. So:
PID1=\$! ← compose sees \$! → host has no `!` var → ""
wait \$PID1 ... ← compose sees \$PID1 → "" → becomes `wait `
SRC="...\$TARGET..." ← \$TARGET still works (set in `environment:`)
cp "\$SRC" "..." ← \$SRC eaten → empty → cp errors silently
Result: the per-PID error check I added in dbf272c never fired
because both lines were `wait` (no args) — which waits for ALL
children and exits with the LAST one's status, not each individually.
A failing arm64 build couldn't fail the script.
Fix: escape every script-local \$ as \$\$. Docker compose translates
\$\$ → literal \$ when materializing the command for the container,
and the in-container shell then expands \$VAR correctly.
Verified by `docker compose config` showing the resolved command
contains \$\$PID1 / \$\$SRC etc (which becomes \$PID1 / \$SRC in the
container's bash).
leeguooooo
947d150561