From 6280dda44382635caada04f1bbd5aeb5e9d1c63f Mon Sep 17 00:00:00 2001
From: Leon Timmermans <fawaka@gmail.com>
Date: Tue, 8 Apr 2025 21:56:05 +0200
Subject: [PATCH 1/2] Don't regenerate mymeta if dynamic_config==0

---
 lib/Module/Build/Base.pm | 20 ++++++++++++--------
 1 file changed, 12 insertions(+), 8 deletions(-)

diff --git a/lib/Module/Build/Base.pm b/lib/Module/Build/Base.pm
index 10b653f9..8ed9f4af 100644
--- a/lib/Module/Build/Base.pm
+++ b/lib/Module/Build/Base.pm
@@ -1927,14 +1927,18 @@ sub create_mymeta {
 
   my $mymeta_obj;
   if ($meta_obj) {
-    # if we have metadata, just update it
-    my %updated = (
-      %{ $meta_obj->as_struct({ version => 2.0 }) },
-      prereqs => $self->_normalize_prereqs,
-      dynamic_config => 0,
-      generated_by => "Module::Build version $Module::Build::VERSION",
-    );
-    $mymeta_obj = CPAN::Meta->new( \%updated, { lazy_validation => 0 } );
+    if ($meta_obj->dynamic_config == 0) {
+      $mymeta_obj = $meta_obj;
+    } else {
+      # if we have metadata, just update it
+      my %updated = (
+        %{ $meta_obj->as_struct({ version => 2.0 }) },
+        prereqs => $self->_normalize_prereqs,
+        dynamic_config => 0,
+        generated_by => "Module::Build version $Module::Build::VERSION",
+      );
+      $mymeta_obj = CPAN::Meta->new( \%updated, { lazy_validation => 0 } );
+    }
   }
   else {
     $mymeta_obj = $self->_get_meta_object(quiet => 0, dynamic => 0, fatal => 1, auto => 0);

From 99cd1c87bb2b9a6dc3f2dc8402223cbc6130411b Mon Sep 17 00:00:00 2001
From: Leon Timmermans <fawaka@gmail.com>
Date: Tue, 8 Apr 2025 22:05:51 +0200
Subject: [PATCH 2/2] Add prereqs in meta_merge to mymeta

---
 lib/Module/Build/Base.pm | 15 ++++++++++++++-
 1 file changed, 14 insertions(+), 1 deletion(-)

diff --git a/lib/Module/Build/Base.pm b/lib/Module/Build/Base.pm
index 8ed9f4af..cc5aec2a 100644
--- a/lib/Module/Build/Base.pm
+++ b/lib/Module/Build/Base.pm
@@ -1931,9 +1931,22 @@ sub create_mymeta {
       $mymeta_obj = $meta_obj;
     } else {
       # if we have metadata, just update it
+      my $prereqs = $self->_normalize_prereqs;
+      if (my $merge = $self->meta_merge) {
+        unless ($merge->{'meta-spec'} && ($merge->{'meta-spec'}{version} // '1.4') eq '2') {
+          require CPAN::Meta::Converter;
+          $merge = CPAN::Meta::Converter->new($merge)->upgrade_fragment;
+        }
+        if ($merge->{prereqs}) {
+          my $left = CPAN::Meta::Prereqs->new($prereqs);
+          my $right = CPAN::Meta::Prereqs->new($merge->{prereqs});
+          $prereqs = $left->with_merged_prereqs($right)->as_string_hash;
+        }
+      }
+
       my %updated = (
         %{ $meta_obj->as_struct({ version => 2.0 }) },
-        prereqs => $self->_normalize_prereqs,
+        prereqs => $prereqs,
         dynamic_config => 0,
         generated_by => "Module::Build version $Module::Build::VERSION",
       );