diff --git a/server-start.sh b/server-start.sh
new file mode 100755
index 0000000..04c316a
--- /dev/null
+++ b/server-start.sh
@@ -0,0 +1,75 @@
+#!/bin/bash
+# simtrace2-pysniff-server startup script
+#
+# Usage: ./server-start.sh [--capture gsmtap|direct] [--port PORT] [--db PATH] [--gsmtap-port PORT]
+#
+# Options set via environment variables act as defaults; CLI flags override them.
+
+set -euo pipefail
+shopt -s nullglob
+
+PROJECT_DIR="$(cd "$(dirname "$0")" && pwd)"
+
+CAPTURE="${CAPTURE:-gsmtap}"
+PORT="${PORT:-8081}"
+DB="${DB:-}"
+GSMTAP_PORT="${GSMTAP_PORT:-4729}"
+
+while [[ $# -gt 0 ]]; do
+    case "$1" in
+        --capture)       CAPTURE="$2"; shift 2 ;;
+        --port)          PORT="$2"; shift 2 ;;
+        --db)            DB="$2"; shift 2 ;;
+        --gsmtap-port)   GSMTAP_PORT="$2"; shift 2 ;;
+        *)               EXTRA_ARGS+=("$1"); shift ;;
+    esac
+done
+
+if [[ "$CAPTURE" == "direct" ]]; then
+    bad_perms=0
+
+    for devdir in /sys/bus/usb/devices/*/; do
+        [[ -f "${devdir}busnum" ]] || continue
+        [[ -f "${devdir}devnum" ]] || continue
+        [[ -f "${devdir}uevent" ]] || continue
+
+        vid=$(grep -oP 'PRODUCT=\K[a-f0-9]+' "${devdir}uevent" 2>/dev/null || true)
+        [[ "$vid" == "1d50" ]] || continue
+
+        busnum=$(<"${devdir}busnum")
+        devnum=$(<"${devdir}devnum")
+        node=$(printf '/dev/bus/usb/%03d/%03d' "$busnum" "$devnum")
+
+        if [[ ! -e "$node" ]]; then
+            continue
+        fi
+
+        if [[ -w "$node" ]]; then
+            break
+        fi
+
+        bad_perms=1
+        echo "Permission denied on $node" >&2
+    done
+
+    if [[ $bad_perms -eq 1 ]]; then
+        echo "" >&2
+        echo "Install the udev rule (then reconnect the device):" >&2
+        echo "──────────────────────────────────────────────────" >&2
+        echo "  sudo cp '$PROJECT_DIR/70-simtrace2-pysniff.rules' /etc/udev/rules.d/" >&2
+        echo "  sudo udevadm control --reload-rules" >&2
+        echo "  sudo udevadm trigger" >&2
+        echo "──────────────────────────────────────────────────" >&2
+        exit 3
+    fi
+fi
+
+ARGS=()
+ARGS+=(--capture "$CAPTURE")
+ARGS+=(--port "$PORT")
+[[ -n "$DB" ]] && ARGS+=(--db "$DB")
+[[ "$CAPTURE" == "gsmtap" ]] && ARGS+=(--gsmtap-port "$GSMTAP_PORT")
+ARGS+=("${EXTRA_ARGS[@]}")
+
+echo "Starting simtrace2-pysniff-server..." >&2
+exec env PYTHONPATH="$PROJECT_DIR" python3 -m simtrace2_pysniff.server "${ARGS[@]}"