diff --git a/start.sh b/start.sh
index 99438bb..b497e71 100755
--- a/start.sh
+++ b/start.sh
@@ -115,6 +115,12 @@ sanitize_assignment() {
   value="${value#\'}"
   value="${value%\'}"
 
+   # Trim leading/trailing whitespace (for safety we assume env values
+   # do not intentionally start or end with spaces)
+   if command -v awk >/dev/null 2>&1; then
+     value=$(printf '%s\n' "$value" | awk '{$1=$1;print}')
+   fi
+
   echo "$value"
 }
 
@@ -271,10 +277,14 @@ update_env() {
 
 ensure_env_default() {
   local key=$1 default=$2
-  local cur
-  cur=$(ini_val "$key")
+  local raw cur
+  raw=$(ini_val "$key")
+  cur=$(sanitize_assignment "$key" "$raw")
   if [[ -z "$cur" ]]; then
     update_env "$key" "$default"
+  elif [[ "$cur" != "$raw" ]]; then
+    # Normalise the existing value if it only differed by quotes/whitespace
+    update_env "$key" "$cur"
   fi
 }
 
@@ -314,11 +324,11 @@ ensure_env_default POSTGRES_HOST "db"
 ensure_env_default POSTGRES_PORT "5432"
 ensure_env_default POSTGRES_FORWARD_PORT "13580"
 
-pg_user=$(ini_val POSTGRES_USER)
-pg_pass=$(ini_val POSTGRES_PASSWORD)
-pg_host=$(ini_val POSTGRES_HOST)
-pg_port=$(ini_val POSTGRES_PORT)
-pg_db=$(ini_val POSTGRES_DB)
+pg_user=$(sanitize_assignment POSTGRES_USER "$(ini_val POSTGRES_USER)")
+pg_pass=$(sanitize_assignment POSTGRES_PASSWORD "$(ini_val POSTGRES_PASSWORD)")
+pg_host=$(sanitize_assignment POSTGRES_HOST "$(ini_val POSTGRES_HOST)")
+pg_port=$(sanitize_assignment POSTGRES_PORT "$(ini_val POSTGRES_PORT)")
+pg_db=$(sanitize_assignment POSTGRES_DB "$(ini_val POSTGRES_DB)")
 update_env DATABASE_URL "postgresql+psycopg2://${pg_user}:${pg_pass}@${pg_host}:${pg_port}/${pg_db}"
 
 ensure_env_default FRONTEND_HTTP_PORT "13300"