diff --git a/functions.sh b/functions.sh
index 6ce72d0..a78f40f 100644
--- a/functions.sh
+++ b/functions.sh
@@ -1,18 +1,18 @@
 #!/usr/bin/env bash
 
 CERT_DIR=~/.letsencrypt_drupal
-TMP_DIR=/tmp/letsencrypt_drupal
+TMP_DIR=/tmp/letsencrypt_drupal_${PROJECT_NAME}
 FILE_BASECONFIG=${TMP_DIR}/baseconfig
 FILE_DRUSH_ALIAS=${TMP_DIR}/drush_alias
 FILE_DRUPAL_VERSION=${TMP_DIR}/drupal_version
 FILE_PROJECT_ROOT=${TMP_DIR}/project_root
+LOCK_FILENAME=/tmp/cert_renew_lock_${PROJECT_NAME}
 
 #---------------------------------------------------------------------
 acquire_lock_or_exit()
 {
   # Check we are not running already: http://mywiki.wooledge.org/BashFAQ/045
-  # @ToDo: Platform specific lock.
-  exec 8>/tmp/cert_renew_lock
+  exec 8>${LOCK_FILENAME}
   if ! flock -n 8  ; then
     logline "Another instance of this script running.";
     exit 1
diff --git a/letsencrypt_drupal.sh b/letsencrypt_drupal.sh
index ab383dd..6785998 100755
--- a/letsencrypt_drupal.sh
+++ b/letsencrypt_drupal.sh
@@ -11,15 +11,23 @@
 # ** 7|8
 # * Path to project root
 # ** Must contain letsencrypt_drupal folder. See readme.
+# * Switches for Dehydrated
+# ** Pass through these command line args to Dehydrated. OK if blank.
 
 # Basic variables.
 DRUSH_ALIAS="$1"
 DRUPAL_VERSION="$2"
 PROJECT_ROOT="$3"
+DEHYDRATED_SWITCHES="$4"
 
 DRUSH_ALIAS_NO_AT="${DRUSH_ALIAS/@/}"
+
+# We need to export these variables so functions.sh can use them.
+export PROJECT_NAME=$(echo "$DRUSH_ALIAS_NO_AT" | cut -d'.' -f1)
+export PROJECT_ENV=$(echo "$DRUSH_ALIAS_NO_AT" | cut -d'.' -f2)
+
 CURRENT_DIR="$( cd "$( dirname "${BASH_SOURCE[0]}" )" && pwd )"
-DEHYDRATED="https://github.com/lukas2511/dehydrated.git"
+DEHYDRATED="https://github.com/dehydrated-io/dehydrated.git"
 
 FILE_DOMAINSTXT=${PROJECT_ROOT}/letsencrypt_drupal/domains_${DRUSH_ALIAS_NO_AT}.txt
 FILE_CONFIG=${PROJECT_ROOT}/letsencrypt_drupal
@@ -102,7 +110,7 @@ main() {
   echo ${DRUPAL_VERSION} > ${FILE_DRUPAL_VERSION}
   echo ${PROJECT_ROOT} > ${FILE_PROJECT_ROOT}
 
-  ${CURRENT_DIR}/dehydrated/dehydrated --config ${FILE_BASECONFIG} --cron --accept-terms
+  ${CURRENT_DIR}/dehydrated/dehydrated --config ${FILE_BASECONFIG} --cron --accept-terms ${DEHYDRATED_SWITCHES}
 }
 
 self_update