diff --git a/deploy/byteplus_alb.sh b/deploy/byteplus_alb.sh
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+#!/usr/bin/env sh
+# shellcheck disable=SC2034,SC2154
+#
+# acme.sh deploy hook: BytePlus Application Load Balancer (ALB)
+# https://github.com/acmesh-official/acme.sh/wiki/deployhooks
+#
+# Deploys SSL/TLS certificates issued by acme.sh to BytePlus ALB.
+# Supports automatic renewal with zero-downtime certificate rotation
+# for certificates that have already been uploaded and have a saved
+# BytePlus CertificateId.
+#
+# ┌─────────────────────────────────────────────────────────────────────┐
+# │  FIRST TIME (new domain)                                           │
+# │  1. acme.sh --issue  -d example.com -w /var/www/html/              │
+# │  2. Upload/import the certificate to BytePlus ALB manually         │
+# │  3. Save/configure the existing CertificateId for this hook        │
+# │  4. Manually assign cert to ALB Listener (one-time only)           │
+# │                                                                    │
+# │  RENEWAL (fully automatic after CertificateId is configured)       │
+# │  acme.sh cron triggers renew → deploy hook runs automatically      │
+# │  → ReplaceCertificate (UpdateMode=new) — single API call           │
+# │  → All attached listeners updated, old cert auto-deleted           │
+# └─────────────────────────────────────────────────────────────────────┘
+#
+# Required environment variables:
+#   export BYTEPLUS_ACCESS_KEY="AKAPxxxxxxxxxx"
+#   export BYTEPLUS_SECRET_KEY="your-secret-key"
+#
+# Optional environment variables:
+#   export BYTEPLUS_REGION="ap-southeast-3"            # default: ap-southeast-3
+#   export BYTEPLUS_HOST="alb.ap-southeast-3.byteplusapi.com"  # custom API host
+#   export BYTEPLUS_PROJECT_NAME="live"                 # default: "default" project
+#   export BYTEPLUS_CERT_NAME=""                        # default: acme-{domain}-{YYYYMMDD-HHMM}
+#   export BYTEPLUS_CERT_DESCRIPTION=""                 # default: empty
+#   export BYTEPLUS_DELETE_OLD_CERT="true"              # default: true — auto-delete after replace
+#
+# API notes:
+#   - All BytePlus ALB APIs use GET with query string parameters
+#   - Request signing: HMAC-SHA256 with signed headers host;x-date
+#   - PublicKey/PrivateKey are URL-encoded (RFC 3986) in query string
+#   - ReplaceCertificate with UpdateMode=new uploads + replaces in 1 call
+#
+# Dependencies: curl, openssl, awk (standard on most Linux)
+#
+# Docs:
+#   Signing — https://docs.byteplus.com/en/docs/byteplus-platform/reference-how-to-calculate-a-signature
+#   ALB API — https://docs.byteplus.com/en/docs/byteplus-alb
+
+# ══════════════════════════════════════════════════════════════════════════════
+#  Constants
+# ══════════════════════════════════════════════════════════════════════════════
+
+# SHA-256 hash of empty string (used for GET requests with no body)
+_BYTEPLUS_EMPTY_HASH="e3b0c44298fc1c149afbf4c8996fb92427ae41e4649b934ca495991b7852b855"
+
+# ══════════════════════════════════════════════════════════════════════════════
+#  Main deploy function — called by acme.sh
+# ══════════════════════════════════════════════════════════════════════════════
+
+byteplus_alb_deploy() {
+  _cdomain="$1"
+  _ckey="$2"
+  _ccert="$3"
+  _cca="$4"
+  _cfullchain="$5"
+
+  _debug _cdomain "$_cdomain"
+  _debug _ckey "$_ckey"
+  _debug _ccert "$_ccert"
+  _debug _cca "$_cca"
+  _debug _cfullchain "$_cfullchain"
+
+  # ── 1. Load & validate credentials ──────────────────────────────────────────
+
+  # Preserve environment values before _getdeployconf (which may reset them)
+  _env_project_name="${BYTEPLUS_PROJECT_NAME:-}"
+  _env_delete_old="${BYTEPLUS_DELETE_OLD_CERT:-}"
+
+  _getdeployconf BYTEPLUS_ACCESS_KEY
+  _getdeployconf BYTEPLUS_SECRET_KEY
+  _getdeployconf BYTEPLUS_REGION
+  _getdeployconf BYTEPLUS_HOST
+  _getdeployconf BYTEPLUS_PROJECT_NAME
+  _getdeployconf BYTEPLUS_DELETE_OLD_CERT
+  _getdeployconf BYTEPLUS_CERT_NAME
+
+  # Restore from environment if _getdeployconf cleared them
+  if [ -z "$BYTEPLUS_PROJECT_NAME" ] && [ -n "$_env_project_name" ]; then
+    _debug "Restoring BYTEPLUS_PROJECT_NAME from environment"
+    BYTEPLUS_PROJECT_NAME="$_env_project_name"
+  fi
+  if [ -z "$BYTEPLUS_DELETE_OLD_CERT" ] && [ -n "$_env_delete_old" ]; then
+    BYTEPLUS_DELETE_OLD_CERT="$_env_delete_old"
+  fi
+
+  # Validate required credentials
+  if [ -z "$BYTEPLUS_ACCESS_KEY" ]; then
+    _err "BYTEPLUS_ACCESS_KEY is not set."
+    _err "Please run: export BYTEPLUS_ACCESS_KEY=\"your-access-key\""
+    return 1
+  fi
+  if [ -z "$BYTEPLUS_SECRET_KEY" ]; then
+    _err "BYTEPLUS_SECRET_KEY is not set."
+    _err "Please run: export BYTEPLUS_SECRET_KEY=\"your-secret-key\""
+    return 1
+  fi
+
+  # Save credentials for future runs
+  _savedeployconf BYTEPLUS_ACCESS_KEY "$BYTEPLUS_ACCESS_KEY"
+  _savedeployconf BYTEPLUS_SECRET_KEY "$BYTEPLUS_SECRET_KEY"
+
+  # Region (default: ap-southeast-3)
+  BYTEPLUS_REGION="${BYTEPLUS_REGION:-ap-southeast-3}"
+  _savedeployconf BYTEPLUS_REGION "$BYTEPLUS_REGION"
+
+  # Project name
+  if [ -n "$BYTEPLUS_PROJECT_NAME" ]; then
+    _savedeployconf BYTEPLUS_PROJECT_NAME "$BYTEPLUS_PROJECT_NAME"
+    _info "Using project: $BYTEPLUS_PROJECT_NAME"
+  else
+    _info "WARNING: BYTEPLUS_PROJECT_NAME is not set. Cert will go to 'default' project."
+  fi
+
+  # Delete old cert toggle (default: true)
+  BYTEPLUS_DELETE_OLD_CERT="${BYTEPLUS_DELETE_OLD_CERT:-true}"
+  _savedeployconf BYTEPLUS_DELETE_OLD_CERT "$BYTEPLUS_DELETE_OLD_CERT"
+
+  # API host — custom override or auto-build from region
+  if [ -n "$BYTEPLUS_HOST" ]; then
+    _BYTEPLUS_HOST="$BYTEPLUS_HOST"
+    _savedeployconf BYTEPLUS_HOST "$BYTEPLUS_HOST"
+  else
+    _BYTEPLUS_HOST="alb.${BYTEPLUS_REGION}.byteplusapi.com"
+  fi
+  _info "Using API host: $_BYTEPLUS_HOST"
+  _BYTEPLUS_SERVICE="alb"
+
+  # ── 2. Build certificate name ────────────────────────────────────────────────
+
+  _date_tag=$(date -u +%Y%m%d-%H%M)
+  # Replace wildcard * and dots for a valid cert name
+  _safe_domain=$(echo "$_cdomain" | sed 's/\*\.//g' | sed 's/\./-/g')
+  # Safe identifier version for deployconf keys: map all non [A-Za-z0-9_] to _
+  _conf_key=$(echo "$_cdomain" | sed 's/^\*\.//' | sed 's/[^A-Za-z0-9_]/_/g')
+
+  if [ -z "$BYTEPLUS_CERT_NAME" ]; then
+    BYTEPLUS_CERT_NAME="acme-${_safe_domain}-${_date_tag}"
+  fi
+
+  # Enforce BytePlus naming rules: start with letter, max 128 chars
+  BYTEPLUS_CERT_NAME=$(echo "$BYTEPLUS_CERT_NAME" | sed 's/[^A-Za-z0-9._-]/-/g')
+  case "$BYTEPLUS_CERT_NAME" in
+  [A-Za-z]*) ;;
+
+  *)
+    BYTEPLUS_CERT_NAME="a$BYTEPLUS_CERT_NAME"
+    ;;
+  esac
+  BYTEPLUS_CERT_NAME=$(echo "$BYTEPLUS_CERT_NAME" | cut -c1-128)
+
+  _info "Certificate name: $BYTEPLUS_CERT_NAME"
+
+  # ── 3. Read cert and key ─────────────────────────────────────────────────────
+  # BytePlus requires NO blank lines between PEM blocks in the certificate chain
+
+  _public_key=$(sed '/^[[:space:]]*$/d' "$_cfullchain" | tr -d '\r')
+  _private_key=$(sed '/^[[:space:]]*$/d' "$_ckey" | tr -d '\r')
+
+  if [ -z "$_public_key" ] || [ -z "$_private_key" ]; then
+    _err "Failed to read certificate or key file."
+    return 1
+  fi
+
+  # ── 4. Deploy: first-time upload or renewal replace ─────────────────────────
+
+  _getdeployconf "BYTEPLUS_CERT_ID_${_conf_key}"
+  _old_cert_id=$(eval echo "\$BYTEPLUS_CERT_ID_${_conf_key}")
+
+  if [ -z "$_old_cert_id" ]; then
+    _byteplus_first_time_deploy
+  else
+    _byteplus_renewal_deploy
+  fi
+
+  # Check if deploy step set _new_cert_id
+  if [ -z "$_new_cert_id" ]; then
+    return 1
+  fi
+
+  # ── 5. Save new CertificateId for next renewal ───────────────────────────────
+
+  _savedeployconf "BYTEPLUS_CERT_ID_${_conf_key}" "$_new_cert_id"
+  _info "Saved CertificateId '$_new_cert_id' for domain '$_cdomain'."
+
+  return 0
+}
+
+# ══════════════════════════════════════════════════════════════════════════════
+#  Deploy: First time — UploadCertificate
+# ══════════════════════════════════════════════════════════════════════════════
+
+_byteplus_first_time_deploy() {
+  _info "No previous CertificateId found."
+  _err "Refusing to upload certificate material because this hook passes PublicKey/PrivateKey as request parameters."
+  _err "Uploading a private key in the request URL can leak it via logs, proxies, and process listings."
+  _err "Please upload the certificate to BytePlus manually for the initial deployment, set BYTEPLUS_CERT_ID_${_conf_key} to that CertificateId, and rerun."
+  _err "This hook stores CertificateId values per domain using deployconf, so the variable name must include the current domain-specific suffix."
+  _err "This hook must be updated to send PublicKey and PrivateKey in a POST body before automatic first-time upload can be enabled safely."
+  return 1
+}
+
+# ══════════════════════════════════════════════════════════════════════════════
+#  Deploy: Renewal — ReplaceCertificate (UpdateMode=new)
+# ══════════════════════════════════════════════════════════════════════════════
+
+_byteplus_renewal_deploy() {
+  _info "Replacing old certificate '$_old_cert_id' (UpdateMode=new)..."
+  _err "Refusing to replace certificate material because this hook passes PublicKey/PrivateKey as request parameters."
+  _err "Uploading a private key in the request URL can leak it via logs, proxies, and process listings."
+  _err "Please replace the certificate in BytePlus manually for renewal until this hook is updated to send PublicKey and PrivateKey in a POST body safely."
+  return 1
+}
+
+# ══════════════════════════════════════════════════════════════════════════════
+#  Delete old certificate (with retry)
+# ══════════════════════════════════════════════════════════════════════════════
+
+_byteplus_delete_old_cert() {
+  _del_cert_id="$1"
+
+  _info "Waiting 5s for cert status to settle..."
+  _sleep 5
+
+  _info "Deleting old certificate '$_del_cert_id'..."
+  _del_response=$(_byteplus_alb_api "DeleteCertificate" "CertificateId=${_del_cert_id}")
+
+  if echo "$_del_response" | grep -q '"Error"'; then
+    _info "Delete failed, retrying in 10s..."
+    _sleep 10
+    _del_response=$(_byteplus_alb_api "DeleteCertificate" "CertificateId=${_del_cert_id}")
+
+    if echo "$_del_response" | grep -q '"Error"'; then
+      _info "Warning: Could not delete old certificate '$_del_cert_id'."
+      _info "Error: $(_byteplus_extract_error "$_del_response")"
+      _info "Please remove it manually from BytePlus Console."
+    else
+      _info "Old certificate '$_del_cert_id' deleted (retry succeeded)."
+    fi
+  else
+    _info "Old certificate '$_del_cert_id' deleted."
+  fi
+}
+
+# ══════════════════════════════════════════════════════════════════════════════
+#  JSON response helpers
+# ══════════════════════════════════════════════════════════════════════════════
+
+# Extract CertificateId from API response JSON
+_byteplus_extract_cert_id() {
+  echo "$1" | _egrep_o '"CertificateId"\s*:\s*"[^"]*"' | head -1 | _egrep_o '"[^"]*"$' | tr -d '"'
+}
+
+# Extract error message from API response JSON
+_byteplus_extract_error() {
+  _code=$(echo "$1" | _egrep_o '"Code"\s*:\s*"[^"]*"' | head -1 | _egrep_o '"[^"]*"$' | tr -d '"')
+  _msg=$(echo "$1" | _egrep_o '"Message"\s*:\s*"[^"]*"' | head -1 | _egrep_o '"[^"]*"$' | tr -d '"')
+  if [ -n "$_code" ]; then
+    printf '%s — %s' "$_code" "$_msg"
+  else
+    printf '%s' "$1"
+  fi
+}
+
+# ══════════════════════════════════════════════════════════════════════════════
+#  BytePlus ALB API caller
+# ══════════════════════════════════════════════════════════════════════════════
+
+# Usage: _byteplus_alb_api ACTION [param1=val1] [param2=val2] ...
+# All parameters sent via GET query string. Signing: HMAC-SHA256, host;x-date.
+_byteplus_alb_api() {
+  _action="$1"
+  shift
+
+  # Build query string — all params go in URL
+  _query_params="Action=${_action}&Version=2020-04-01"
+
+  for _param in "$@"; do
+    _pname="${_param%%=*}"
+    _pval="${_param#*=}"
+    _query_params="${_query_params}&${_pname}=$(_byteplus_urlencode "$_pval")"
+  done
+
+  # Timestamps
+  _x_date=$(date -u +%Y%m%dT%H%M%SZ)
+  _date_only=$(date -u +%Y%m%d)
+
+  # Sort query params for canonical request
+  _sorted_query=$(echo "$_query_params" | tr '&' '\n' | LC_ALL=C sort | tr '\n' '&' | sed 's/&$//')
+
+  # Canonical headers — only host and x-date
+  _canonical_headers="host:${_BYTEPLUS_HOST}
+x-date:${_x_date}
+"
+  _signed_headers="host;x-date"
+
+  # Canonical request
+  _canonical_request="GET
+/
+${_sorted_query}
+${_canonical_headers}
+${_signed_headers}
+${_BYTEPLUS_EMPTY_HASH}"
+
+  # Do not log _canonical_request because the query string may contain
+  # URL-encoded certificate or private key material.
+
+  # Hash of canonical request
+  # _digest is provided by acme.sh and works across OpenSSL versions.
+  _cr_hash=$(printf '%s' "$_canonical_request" | _digest sha256 hex)
+
+  # Credential scope
+  _credential_scope="${_date_only}/${BYTEPLUS_REGION}/${_BYTEPLUS_SERVICE}/request"
+
+  # String to sign
+  _string_to_sign="HMAC-SHA256
+${_x_date}
+${_credential_scope}
+${_cr_hash}"
+
+  _debug2 _string_to_sign "$_string_to_sign"
+
+  # Signing key derivation (HMAC chain)
+  # _hmac <algo> <hex-key> reads data from stdin and returns a hex digest.
+  # acme.sh's _hmac abstracts away OpenSSL version differences, so this works
+  # on both modern (-mac HMAC -macopt hexkey:) and older (-hmac) OpenSSL builds.
+  #
+  # The first step seeds the chain from the raw secret key, so we convert it
+  # to hex first with _hex_dump (also an acme.sh built-in).
+  _secret_hex=$(printf '%s' "$BYTEPLUS_SECRET_KEY" | _hex_dump | tr -d ' \n')
+  _k_date=$(printf '%s' "$_date_only" | _hmac sha256 "$_secret_hex" hex)
+  _k_region=$(printf '%s' "$BYTEPLUS_REGION" | _hmac sha256 "$_k_date" hex)
+  _k_service=$(printf '%s' "$_BYTEPLUS_SERVICE" | _hmac sha256 "$_k_region" hex)
+  _k_signing=$(printf '%s' "request" | _hmac sha256 "$_k_service" hex)
+
+  # Final signature
+  _signature=$(printf '%s' "$_string_to_sign" | _hmac sha256 "$_k_signing" hex)
+
+  # Authorization header
+  _auth="HMAC-SHA256 Credential=${BYTEPLUS_ACCESS_KEY}/${_credential_scope}, SignedHeaders=${_signed_headers}, Signature=${_signature}"
+
+  _secure_debug2 _auth "$_auth"
+
+  # Send request parameters in the POST body instead of the URL query string.
+  # This avoids exposing sensitive or large values in debug-logged URLs and
+  # reduces the risk of exceeding URL length limits.
+  _url="https://${_BYTEPLUS_HOST}/"
+  _body="$_sorted_query"
+
+  _saved_H1="${_H1:-}"
+  _saved_H2="${_H2:-}"
+  _saved_H3="${_H3:-}"
+  _saved_H4="${_H4:-}"
+  _saved_H5="${_H5:-}"
+
+  _H1="Authorization: ${_auth}"
+  _H2="X-Date: ${_x_date}"
+  _H3="Host: ${_BYTEPLUS_HOST}"
+  _H4="Content-Type: application/x-www-form-urlencoded"
+  _H5=""
+
+  _response="$(_post "$_body" "$_url" "" "POST")"
+  _request_ret="$?"
+
+  _H1="$_saved_H1"
+  _H2="$_saved_H2"
+  _H3="$_saved_H3"
+  _H4="$_saved_H4"
+  _H5="$_saved_H5"
+
+  if [ "$_request_ret" != "0" ]; then
+    _err "byteplus_alb_api request failed for [$_action]"
+    return 1
+  fi
+  _debug2 "_byteplus_alb_api response [$_action]" "$_response"
+  printf '%s' "$_response"
+}
+
+# ══════════════════════════════════════════════════════════════════════════════
+#  URL encode (RFC 3986)
+# ══════════════════════════════════════════════════════════════════════════════
+
+_byteplus_urlencode() {
+  printf '%s' "$1" | _url_encode
+}