The previous SIGNUM variable was required (${SIGNUM:?...}), which
broke for users with their own OS accounts who shouldn't need to set
anything manually. Replace with ${SIGNUM:-${USER}} so:
- Own-account mode: leave SIGNUM unset in .env — project name and
container name default to devbox-$USER automatically. Each OS
user gets isolated volumes with zero configuration.
- Shared-account mode: set SIGNUM=<id> in .env as before.
Both container_name and the top-level name: field use the same
fallback, so volumes and container names stay consistent.
Updated .env.shared.example to document both modes with the SIGNUM
line commented out by default (own-account is the common case).
The Docker daemon is system-wide — named volumes are prefixed by the
compose project name, which defaults to the basename of the directory
holding docker-compose.yml. Two users whose compose file lives under
a directory with the same name (e.g. ~/alice/opencode-devbox and
~/bob/opencode-devbox) would silently share volumes, corrupting each
other's opencode data, bash history, and TUI settings.
Add an explicit top-level 'name: devbox-${SIGNUM}' so the project
name (and therefore all volume prefixes) is unique per user. The old
comment claiming directory-name prefixing was sufficient was wrong —
it only works if directory basenames differ, which isn't guaranteed
on multi-user hosts or when users follow the same setup instructions.
Two changes that address a longstanding frustration: bash history is
lost on every container recreate, and the container's ~/.bashrc and
~/.inputrc are stock Debian (no history tuning, no prefix search on
arrow keys, no integrations).
Added a named volume 'devbox-shell-history' mounted at ~/.cache/bash
with HISTFILE pointing there; history now survives 'docker compose up
--force-recreate'. The volume is added to both docker-compose.yml and
docker-compose.shared.yml, and ~/.cache/bash is registered in the
entrypoint ownership-fix loop per the AGENTS.md convention.
Baked rootfs/home/developer/.bash_aliases (sourced automatically by
Debian's default ~/.bashrc) and rootfs/home/developer/.inputrc into
the image. They give new containers: 100k-entry timestamped dedup
history with per-prompt flush, Up/Down arrow prefix history search,
case-insensitive coloured completion, aliases that prefer eza and
bat when present, git shortcuts, interactive rm/mv/cp, zoxide and
fzf (via 'fzf --bash') integration, and a [devbox] prompt marker.
The fzf integration uses 'fzf --bash' because we install fzf from
GitHub releases, not apt — the apt-path key-bindings aren't present.
Users who prefer their host's own shell config can uncomment two
commented bind-mount lines in docker-compose.yml to shadow the
baked defaults.
For machines where multiple users share one OS account. Each user gets
isolated containers, config, and named volumes by running docker compose
from their own directory with a unique SIGNUM in .env.
joakimp