Persist zoxide directory history across container recreations

Zoxide stores its database at ~/.local/share/zoxide/db.zo. Without a
named volume, the 'z <fragment>' jump targets are lost on every
'docker compose up --force-recreate'.

Add devbox-zoxide named volume in docker-compose.yml and
docker-compose.shared.yml, add ~/.local/share/zoxide to the
entrypoint ownership-fix loop per AGENTS.md convention, and update
the data-persistence tables in README.md and DOCKER_HUB.md.

.env.shared.example

@@ -1,7 +1,13 @@
 # ── Shared machine setup ─────────────────────────────────────────────
-# Your corporate signum / username (REQUIRED)
-# This isolates your container, config, and data from other users.
-SIGNUM=your-signum-here
+# SIGNUM isolates your container name and named volumes from other users.
+#
+# Own-account mode (each user has their own OS login):
+#   Leave SIGNUM commented out — it defaults to your OS username ($USER).
+# SIGNUM=
+#
+# Shared-account mode (everyone logs in as the same OS user):
+#   Uncomment and set to your unique identifier.
+# SIGNUM=your-signum-here
 
 # ── Provider ─────────────────────────────────────────────────────────
 OPENCODE_PROVIDER=amazon-bedrock

DOCKER_HUB.md

@@ -228,6 +228,7 @@ Understanding what survives container restarts and what doesn't:
 | `/home/developer/.local/share/opencode` | Named volume (if configured) | ✅ Yes — Docker volume | Session history, memory, auth tokens |
 | `/home/developer/.local/state/opencode` | Named volume (if configured) | ✅ Yes — Docker volume | TUI settings (theme, toggles) |
 | `/home/developer/.cache/bash` | Named volume `devbox-shell-history` | ✅ Yes — Docker volume | Bash history (`$HISTFILE`) — survives container recreate |
+| `/home/developer/.local/share/zoxide` | Named volume `devbox-zoxide` | ✅ Yes — Docker volume | Zoxide directory history (`z <fragment>` jump targets) |
 | `/home/developer/.local/share/uv` | Named volume (if configured) | ✅ Yes — Docker volume | Python installs, uv tool installs |
 | `/home/developer/.rustup` | Named volume (if configured) | ✅ Yes — Docker volume | Rust toolchains |
 | `/home/developer/.cargo` | Named volume (if configured) | ✅ Yes — Docker volume | Cargo binaries, registry cache |
@@ -547,6 +548,10 @@ ping all agents
 
 All six agents should respond if your provider authentication is working.
 
+## Multi-User Setup
+
+This guide covers single-user setup. For running multiple opencode-devbox instances in parallel — whether each user has their own OS account or everyone shares one login — see the [Multi-user setup section](https://gitea.jordbo.se/joakimp/opencode-devbox#multi-user-setup) in the source repository. It covers volume isolation, the `docker-compose.shared.yml` layout, and the `SIGNUM` / `$USER` auto-detection mechanism.
+
 ## Source
 
 Build from source or contribute: [opencode-devbox on Gitea](https://gitea.jordbo.se/joakimp/opencode-devbox)

Dockerfile

@@ -5,7 +5,7 @@ ARG DEBIAN_VERSION=trixie-slim
 FROM debian:${DEBIAN_VERSION} AS base
 
 ARG TARGETARCH
-ARG OPENCODE_VERSION=1.14.20
+ARG OPENCODE_VERSION=1.14.21
 
 LABEL maintainer="joakimp"
 LABEL description="Portable opencode developer container"

README.md

@@ -273,11 +273,17 @@ volumes:
   - devbox-vscode:/home/developer/.vscode-server
 ```
 
-### Shared machine setup (multiple users, single OS account)
+### Multi-user setup
 
-For machines where multiple users share one OS account (e.g. a common `garage` user), a separate compose file isolates each user's config and data using a `SIGNUM` variable.
+The shared-machine compose file (`docker-compose.shared.yml`) supports two modes:
 
-Each user creates their own directory and setup:
+**Own-account mode** (each user has their own OS login — the common case):
+Leave `SIGNUM` unset in `.env`. The project name defaults to `devbox-$USER`, so each OS user automatically gets isolated container names and named volumes with zero configuration.
+
+**Shared-account mode** (everyone logs in as the same OS user, e.g. `garage`):
+Each user sets `SIGNUM=<unique-id>` in `.env` to get isolation.
+
+Setup per user:
 
 ```bash
 # Replace <signum> with your username/identifier
@@ -291,17 +297,17 @@ cp /path/to/opencode-devbox/.env.shared.example .env
 # Create per-user config directory
 mkdir -p ~/<signum>/.config/opencode
 
-# Edit .env with your signum, provider, keys, etc.
+# Edit .env — set SIGNUM only if you're in shared-account mode
 vim .env
 
 # Start
 docker compose up -d
-docker compose exec -u developer devbox-<signum> opencode
+docker compose exec -u developer devbox opencode
 ```
 
 Each user's container, config, and named volumes are fully isolated:
-- Container name: `devbox-<signum>` (no collisions)
-- Named volumes: prefixed with the project directory name (automatic per-user isolation)
+- Container name: `devbox-<signum>` (or `devbox-$USER` in own-account mode)
+- Named volumes: prefixed with the project name (`devbox-<signum>_devbox-data`, etc.) — the Docker daemon is system-wide, so directory-name prefixing alone is NOT sufficient for isolation
 - Opencode config: `~/<signum>/.config/opencode/` (per-user settings, OMOS config, etc.)
 
 See `docker-compose.shared.yml` and `.env.shared.example` for the full configuration.
@@ -460,6 +466,8 @@ Defaults you get out of the box:
 - ~/.inputrc:/home/developer/.inputrc:ro
 ```
 
+> **Single-file bind-mount caveat (all platforms):** Docker bind-mounts the file's **inode**, not its path. When editors like vim, nvim, VS Code, or `sed -i` save a file, they write to a temp file and `rename()` it over the original — creating a new inode. The container stays pinned to the old (now unlinked) inode and never sees the update. This is a kernel limitation ([Docker #15793](https://github.com/moby/moby/issues/15793)), not fixable by Docker. Append-only writes (`echo "alias foo=bar" >> file`) are safe because they modify the same inode. **Workaround:** mount the parent directory instead of the single file (e.g. `~/.config/devbox-shell:/home/developer/.config/devbox-shell:ro`) and source files from there.
+
 **Option B — customize inside the container.** Just edit `~/.bash_aliases` or `~/.inputrc` as normal. Pair this with a bind-mount or named volume on the home dir if you want the edits to survive container recreation.
 
 ### Restoring or diffing defaults
@@ -540,6 +548,7 @@ Container (Debian trixie)
 | `/home/developer/.local/share/opencode` | Named volume `devbox-data` | ✅ Yes | Session history, memory |
 | `/home/developer/.local/state/opencode` | Named volume `devbox-state` | ✅ Yes | TUI settings (theme, toggles) |
 | `/home/developer/.cache/bash` | Named volume `devbox-shell-history` | ✅ Yes | Bash history (`$HISTFILE`), survives container recreate |
+| `/home/developer/.local/share/zoxide` | Named volume `devbox-zoxide` | ✅ Yes | Zoxide directory history (`z <fragment>` jump targets) |
 | `/home/developer/.local/share/uv` | Named volume `devbox-uv` (if configured) | ✅ Yes | Python installs, uv tool installs |
 | `/home/developer/.rustup` | Named volume `devbox-rustup` (if configured) | ✅ Yes | Rust toolchains |
 | `/home/developer/.cargo` | Named volume `devbox-cargo` (if configured) | ✅ Yes | Cargo binaries, registry cache |

deploy/README.md

@@ -198,6 +198,34 @@ After editing `docker-compose.yml` on the VM to uncomment the bind mounts you ne
 
 The script reads `docker-compose.yml` on the remote VM, detects which bind mounts are active, and syncs only those directories from your local machine. It also creates the remote directories if they don't exist.
 
+### Upgrading an existing VM to a new release
+
+Each tagged release may add new named volumes or bind-mount lines to `docker-compose.yml`. Pulling a new image via `docker compose pull` grabs the new container behaviour, but compose files on the VM are user-owned and never touched by the image — you have to reconcile them yourself when upgrading across versions.
+
+**Symptom of a missed reconcile:** a new feature quietly doesn't work even though the image is correct. Example from v1.14.19c → v1.14.20: bash history persistence requires the `devbox-shell-history` named volume mounted at `/home/developer/.cache/bash`. The v1.14.20 image writes history to that path either way, but without the volume mount on the VM, writes land in the container's writable layer and vanish on every `--force-recreate`.
+
+**Upgrade ritual:**
+
+```bash
+# On the VM, before recreating the container:
+cd ~/opencode-devbox
+cp docker-compose.yml docker-compose.yml.bak-$(date +%Y%m%d-%H%M%S)
+
+# Compare against the repo version to see what's new:
+#   (from your local checkout)
+scp devbox-affection:~/opencode-devbox/docker-compose.yml /tmp/vm-compose.yml
+diff -u /tmp/vm-compose.yml ~/src/src_local/opencode-devbox/docker-compose.yml
+```
+
+For each new `volumes:` entry or mount line in the repo version that isn't in your VM's file, add it manually — preserving any local customizations you've made (image variant, read/write flags on bind mounts, etc.). Then:
+
+```bash
+docker compose config >/dev/null   # verify YAML still parses
+docker compose up -d --force-recreate
+```
+
+If you maintain the VM's compose file with no local changes, `scp` the repo version over wholesale. If you have customizations (the common case), do the diff-and-merge by hand.
+
 ### Shell defaults inside the container
 
 The image ships baked `.bash_aliases` and `.inputrc` in `/etc/skel-devbox/` — quality-of-life defaults (prefix history search on Up/Down arrows, persistent history across container recreates via the `devbox-shell-history` named volume, `[devbox]` prompt marker, sensible aliases). On first container start the entrypoint copies them to `/home/developer/` **only if the target file does not already exist**.

docker-compose.shared.yml

@@ -12,14 +12,24 @@
 #   5. mkdir -p ~/<signum>/.config/opencode
 #   6. docker compose up -d
 #
-# Named volumes are automatically isolated per user because Docker Compose
-# prefixes them with the project directory name (e.g. opencode-devbox_devbox-data).
-# Since each user runs from ~/<signum>/opencode-devbox/, volumes don't collide.
+# Volume isolation: the top-level 'name:' field derives a unique project
+# name per user, which Docker Compose uses as the prefix for all named
+# volumes. Without this, two users whose compose file lives in a directory
+# with the same basename would share volumes — the Docker daemon is
+# system-wide and doesn't scope by OS user.
+#
+# Two modes:
+#   Own-account mode (each user has their own OS login):
+#     Leave SIGNUM unset in .env — it defaults to $USER automatically.
+#   Shared-account mode (everyone logs in as the same OS user):
+#     Set SIGNUM=<unique-id> in .env so each person gets isolated volumes.
+
+name: devbox-${SIGNUM:-${USER}}
 
 services:
   devbox:
     image: joakimp/opencode-devbox:latest
-    container_name: devbox-${SIGNUM:?Set SIGNUM in .env}
+    container_name: devbox-${SIGNUM:-${USER}}
     stdin_open: true
     tty: true
     env_file:
@@ -42,6 +52,9 @@ services:
       # Persist bash history across container recreations
       - devbox-shell-history:/home/developer/.cache/bash
 
+      # Persist zoxide directory history ('z <fragment>' to jump)
+      - devbox-zoxide:/home/developer/.local/share/zoxide
+
       # Persist uv data (Python installs)
       - devbox-uv:/home/developer/.local/share/uv
 
@@ -51,4 +64,5 @@ services:
 volumes:
   devbox-data:
   devbox-shell-history:
+  devbox-zoxide:
   devbox-uv:

docker-compose.yml

@@ -8,6 +8,11 @@
 # Or for interactive one-shot:
 #   docker compose run --rm devbox
 
+# Pin the project name so named volumes survive directory renames.
+# Without this, Docker Compose derives the project name from the
+# directory basename — renaming the dir orphans all existing volumes.
+name: opencode-devbox
+
 services:
   devbox:
     image: joakimp/opencode-devbox:latest
@@ -56,9 +61,19 @@ services:
       # Without this, ~/.bash_history is lost on 'docker compose up --force-recreate'.
       - devbox-shell-history:/home/developer/.cache/bash
 
+      # Persist zoxide directory history ('z <fragment>' to jump).
+      - devbox-zoxide:/home/developer/.local/share/zoxide
+
       # Optional: override baked shell defaults with your host's rc files.
       # The image ships sensible defaults (history tuning, prefix-search on
       # Up/Down arrows, fzf/zoxide integration). Uncomment to use your own:
+      #
+      # NOTE: Single-file bind-mounts break when editors use atomic save
+      # (vim, VS Code, sed -i write a temp file then rename() over the
+      # original, creating a new inode the container never sees). This is a
+      # kernel limitation, not Docker-specific. If host edits stop appearing
+      # in the container, mount the parent directory instead — see the
+      # "Shell defaults" section in README.md.
       # - ~/.bash_aliases:/home/developer/.bash_aliases:ro
       # - ~/.inputrc:/home/developer/.inputrc:ro
 
@@ -81,6 +96,7 @@ volumes:
   devbox-data:
   devbox-state:
   devbox-shell-history:
+  devbox-zoxide:
   devbox-uv:
   # devbox-rustup:
   # devbox-cargo:

entrypoint.sh

@@ -77,6 +77,7 @@ for dir in \
   /home/"$USER_NAME"/.local/share/opencode \
   /home/"$USER_NAME"/.local/state/opencode \
   /home/"$USER_NAME"/.local/share/uv \
+  /home/"$USER_NAME"/.local/share/zoxide \
   /home/"$USER_NAME"/.cache/bash \
   /home/"$USER_NAME"/.rustup \
   /home/"$USER_NAME"/.cargo \