diff --git a/.gitignore b/.gitignore
index 25e5a08..cab97ec 100644
--- a/.gitignore
+++ b/.gitignore
@@ -24,3 +24,4 @@
 ollama_backends.json
 .python/
 cpython-*.tar.gz
+docker-compose-linux-*
diff --git a/deploy/README.md b/deploy/README.md
index e4ec795..7a3c63b 100644
--- a/deploy/README.md
+++ b/deploy/README.md
@@ -16,14 +16,17 @@
 
 What `install.sh` does (idempotent — safe to re-run, e.g. after `git pull`):
 
-1. Checks prerequisites: Docker + compose plugin, and a Python ≥ 3.11.
+1. Checks prerequisites: Docker, and a Python ≥ 3.11.
    If the system has none (Ubuntu 18.04 ships 3.6, 22.04 ships 3.10 — and
    the system python must never be replaced), the script fetches a
    standalone CPython build into `.python/` inside the repo — self-contained,
    needs only glibc ≥ 2.17, so it runs on any distro, old or new. The
    downloaded tarball is kept next to the repo root and reused on re-runs;
    for an offline server, drop the tarball next to `install.sh` beforehand
-   and it will be picked up instead of downloading.
+   and it will be picked up instead of downloading. Same for the docker
+   compose plugin: if the host doesn't have `docker compose` (18.04's docker
+   packages predate it), the script installs the compose v2 binary itself
+   into `/usr/local/lib/docker/cli-plugins/`.
 2. Provisions `.env` — on the `deploy` branch it already ships with the
    deployment defaults (web UI off, auth off, Ollama Cloud, profile
    `navi_code`); the script generates the DB password in place of the
diff --git a/deploy/install.sh b/deploy/install.sh
index 4363ade..3d9c0b7 100755
--- a/deploy/install.sh
+++ b/deploy/install.sh
@@ -90,8 +90,42 @@
 if ! command -v docker >/dev/null; then
     err "docker not found — install Docker (https://docs.docker.com/engine/install/) first"; exit 1
 fi
+
+# compose v2: use the existing plugin, or auto-install it (single static
+# binary; works on any distro with docker CLI >= 18.09). System-wide path —
+# so `sudo docker compose` sees it too. Pre-downloaded binary next to
+# install.sh wins on offline servers.
 if ! $SUDO docker compose version >/dev/null 2>&1; then
-    err "docker compose (v2 plugin) not available"; exit 1
+    say "docker compose v2 not found — installing the plugin"
+    case "$(uname -m)" in
+        x86_64)       COMPOSE_ASSET="docker-compose-linux-x86_64" ;;
+        aarch64|arm64) COMPOSE_ASSET="docker-compose-linux-aarch64" ;;
+        *) err "unsupported architecture for compose: $(uname -m)"; exit 1 ;;
+    esac
+    $SUDO mkdir -p /usr/local/lib/docker/cli-plugins
+    DEST="/usr/local/lib/docker/cli-plugins/docker-compose"
+    if [ -f "$REPO_DIR/$COMPOSE_ASSET" ]; then
+        $SUDO cp "$REPO_DIR/$COMPOSE_ASSET" "$DEST"
+    else
+        URL="https://github.com/docker/compose/releases/latest/download/$COMPOSE_ASSET"
+        if command -v curl >/dev/null; then
+            $SUDO curl -fsSL --retry 3 -o "$DEST" "$URL" || { err "compose download failed: $URL"; exit 1; }
+        elif command -v wget >/dev/null; then
+            $SUDO wget -q -O "$DEST" "$URL" || { err "compose download failed: $URL"; exit 1; }
+        else
+            err "no curl/wget on the host. Download on another machine:"
+            err "  $URL"
+            err "put the file next to install.sh and re-run."
+            exit 1
+        fi
+    fi
+    $SUDO chmod +x "$DEST"
+    if ! $SUDO docker compose version >/dev/null 2>&1; then
+        err "compose plugin installed but docker doesn't pick it up —"
+        err "the docker CLI is probably older than 18.09 (no plugin support)."
+        err "Report the output of: docker --version"
+        exit 1
+    fi
 fi
 echo "OK: python ($($PYBIN --version 2>&1)), docker + compose"