diff --git a/REFERENCE.md b/REFERENCE.md
index 9e53411f..3aada6ab 100644
--- a/REFERENCE.md
+++ b/REFERENCE.md
@@ -49,6 +49,12 @@ file on an haproxy load balancer.
 * `haproxy::mailer::collect_exported`
 * `haproxy::service`: HAProxy service
 
+### Functions
+
+* [`haproxy::generate_error_message`](#haproxy--generate_error_message): Function created to generate error message. Any string as error message can be passed and the function can be called in epp templates.
+* [`haproxy::sort_bind`](#haproxy--sort_bind)
+* [`haproxy::validate_ip_addr`](#haproxy--validate_ip_addr)
+
 ## Classes
 
 ### <a name="haproxy"></a>`haproxy`
@@ -714,6 +720,7 @@ The following parameters are available in the `haproxy::defaults` defined type:
 
 * [`options`](#-haproxy--defaults--options)
 * [`sort_options_alphabetic`](#-haproxy--defaults--sort_options_alphabetic)
+* [`merge_options`](#-haproxy--defaults--merge_options)
 * [`instance`](#-haproxy--defaults--instance)
 
 ##### <a name="-haproxy--defaults--options"></a>`options`
@@ -733,6 +740,16 @@ Defaults to true.
 
 Default value: `true`
 
+##### <a name="-haproxy--defaults--merge_options"></a>`merge_options`
+
+Data type: `Boolean`
+
+Whether to merge the user-supplied `options` hash with the
+`default_options` values set in params.pp. Merging allows to change
+or add options without having to recreate the entire hash.
+
+Default value: `$haproxy::params::merge_options`
+
 ##### <a name="-haproxy--defaults--instance"></a>`instance`
 
 Data type: `String`
@@ -2010,3 +2027,61 @@ Optional. Defaults to 'haproxy'
 
 Default value: `'haproxy'`
 
+## Functions
+
+### <a name="haproxy--generate_error_message"></a>`haproxy::generate_error_message`
+
+Type: Ruby 4.x API
+
+Function created to generate error message. Any string as error message can be passed and the function can
+be called in epp templates.
+
+#### `haproxy::generate_error_message(String $error_message)`
+
+Function created to generate error message. Any string as error message can be passed and the function can
+be called in epp templates.
+
+Returns: `Any`
+
+##### `error_message`
+
+Data type: `String`
+
+
+
+### <a name="haproxy--sort_bind"></a>`haproxy::sort_bind`
+
+Type: Ruby 4.x API
+
+The haproxy::sort_bind function.
+
+#### `haproxy::sort_bind(Hash $bind)`
+
+The haproxy::sort_bind function.
+
+Returns: `Array`
+
+##### `bind`
+
+Data type: `Hash`
+
+
+
+### <a name="haproxy--validate_ip_addr"></a>`haproxy::validate_ip_addr`
+
+Type: Ruby 4.x API
+
+The haproxy::validate_ip_addr function.
+
+#### `haproxy::validate_ip_addr(String $virtual_ip)`
+
+The haproxy::validate_ip_addr function.
+
+Returns: `Boolean`
+
+##### `virtual_ip`
+
+Data type: `String`
+
+
+
diff --git a/manifests/defaults.pp b/manifests/defaults.pp
index 636d33fc..a3bb838c 100644
--- a/manifests/defaults.pp
+++ b/manifests/defaults.pp
@@ -16,12 +16,18 @@
 #   Sort options either alphabetic or custom like haproxy internal sorts them.
 #   Defaults to true.
 #
+# @param merge_options
+#   Whether to merge the user-supplied `options` hash with the
+#   `default_options` values set in params.pp. Merging allows to change
+#   or add options without having to recreate the entire hash.
+#
 # @param instance
 #   Optional. Defaults to 'haproxy'.
 #
 define haproxy::defaults (
   Hash    $options                  = {},
   Boolean $sort_options_alphabetic  = true,
+  Boolean $merge_options            = $haproxy::params::merge_options,
   String  $instance                 = 'haproxy',
 ) {
   if $instance == 'haproxy' {
@@ -36,9 +42,16 @@
   include haproxy::globals
   $_sort_options_alphabetic = pick($sort_options_alphabetic, $haproxy::globals::sort_options_alphabetic)
 
+  $defaults_options = pick($options, $haproxy::params::defaults_options)
+  if $merge_options {
+    $_defaults_options = $haproxy::params::defaults_options + $defaults_options
+  } else {
+    $_defaults_options = $defaults_options
+  }
+
   $parameters = {
     '_sort_options_alphabetic' => $_sort_options_alphabetic,
-    'options'                  => $options,
+    'options'                  => $_defaults_options,
     'name'                     => $name,
   }
 
diff --git a/spec/defines/defaults_spec.rb b/spec/defines/defaults_spec.rb
index 302b8e41..47ed6e44 100644
--- a/spec/defines/defaults_spec.rb
+++ b/spec/defines/defaults_spec.rb
@@ -25,7 +25,8 @@
   context 'with a single option' do
     let(:params) do
       {
-        options: { 'balance' => 'roundrobin' }
+        options: { 'balance' => 'roundrobin' },
+        merge_options: false
       }
     end
 
@@ -37,4 +38,37 @@
       )
     }
   end
+
+  context 'with merge defaults true' do
+    let(:params) do
+      {
+        options: { 'balance' => 'roundrobin' }
+      }
+    end
+
+    defaults_output = <<~EXPECTEDOUTPUT
+
+
+      defaults test
+        balance roundrobin
+        log global
+        maxconn 8000
+        option redispatch
+        retries 3
+        stats enable
+        timeout http-request 10s
+        timeout queue 1m
+        timeout connect 10s
+        timeout client 1m
+        timeout server 1m
+        timeout check 10s
+    EXPECTEDOUTPUT
+    it {
+      is_expected.to contain_concat__fragment('haproxy-test_defaults_block').with(
+        'order' => '25-test',
+        'target' => '/tmp/haproxy.cfg',
+        'content' => defaults_output,
+      )
+    }
+  end
 end