diff --git a/src/builder-utils.c b/src/builder-utils.c
index 01d981b5..51bb7f1d 100644
--- a/src/builder-utils.c
+++ b/src/builder-utils.c
@@ -51,6 +51,11 @@ G_DEFINE_AUTO_CLEANUP_CLEAR_FUNC (yaml_parser_t, yaml_parser_delete)
 G_DEFINE_AUTO_CLEANUP_CLEAR_FUNC (yaml_document_t, yaml_document_delete)
 #endif
 
+typedef struct {
+  int opath_fd;
+  char *name;
+} LocaleFile;
+
 char *
 builder_uri_to_filename (const char *uri)
 {
@@ -283,78 +288,347 @@ directory_is_empty (const char *path)
   return empty;
 }
 
+static void
+locale_file_free (gpointer p)
+{
+  LocaleFile *lf = p;
+  glnx_close_fd (&lf->opath_fd);
+  g_free (lf->name);
+  g_free (lf);
+}
+
 static gboolean
-migrate_locale_dir (GFile      *source_dir,
-                    GFile      *separate_dir,
-                    const char *subdir,
-                    GError    **error)
+collect_dir_names (int         dfd,
+                   GPtrArray **out_names,
+                   GError    **error)
 {
-  g_autoptr(GFileEnumerator) dir_enum = NULL;
-  GFileInfo *next;
-  GError *temp_error = NULL;
+  g_auto(GLnxDirFdIterator) iter = { 0, };
+  g_autoptr(GPtrArray) names = g_ptr_array_new_with_free_func (g_free);
+  struct stat dir_st;
+  struct dirent *dent;
 
-  dir_enum = g_file_enumerate_children (source_dir, "standard::name,standard::type",
-                                        G_FILE_QUERY_INFO_NOFOLLOW_SYMLINKS,
-                                        NULL, NULL);
-  if (!dir_enum)
-    return TRUE;
+  if (!glnx_dirfd_iterator_init_at (dfd, ".", FALSE, &iter, error))
+    return FALSE;
+
+  if (fstat (iter.fd, &dir_st) < 0)
+    return glnx_throw_errno_prefix (error, "fstat dir");
 
-  while ((next = g_file_enumerator_next_file (dir_enum, NULL, &temp_error)))
+  while (TRUE)
     {
-      g_autoptr(GFileInfo) child_info = next;
-      g_autoptr(GFile) locale_subdir = NULL;
+      glnx_autofd int opath_fd = -1;
+      struct stat st;
+
+      if (!glnx_dirfd_iterator_next_dent_ensure_dtype (&iter, &dent, NULL, error))
+        return FALSE;
 
-      if (g_file_info_get_file_type (child_info) == G_FILE_TYPE_DIRECTORY)
+      if (dent == NULL)
+        break;
+
+      if (dent->d_type != DT_DIR)
+        continue;
+
+      opath_fd = openat (iter.fd, dent->d_name,
+                         O_PATH | O_NOFOLLOW | O_CLOEXEC);
+      if (opath_fd < 0)
         {
-          g_autoptr(GFile) child = NULL;
-          const char *name = g_file_info_get_name (child_info);
-          g_autofree char *language = g_strdup (name);
-          g_autofree char *relative = NULL;
-          g_autofree char *target = NULL;
-          char *c;
-
-          c = strchr (language, '@');
-          if (c != NULL)
-            *c = 0;
-          c = strchr (language, '_');
-          if (c != NULL)
-            *c = 0;
-          c = strchr (language, '.');
-          if (c != NULL)
-            *c = 0;
-
-          /* We ship english and C locales always */
-          if (strcmp (language, "C") == 0 ||
-              strcmp (language, "en") == 0)
+          if (G_IN_SET (errno, ENOENT, EACCES))
             continue;
+          return glnx_throw_errno_prefix (error, "openat %s", dent->d_name);
+        }
 
-          child = g_file_get_child (source_dir, g_file_info_get_name (child_info));
+      if (fstat (opath_fd, &st) < 0)
+        return glnx_throw_errno_prefix (error, "fstat %s", dent->d_name);
 
-          relative = g_build_filename (language, subdir, name, NULL);
-          locale_subdir = g_file_resolve_relative_path (separate_dir, relative);
-          if (!flatpak_mkdir_p (locale_subdir, NULL, error))
-            return FALSE;
+      if (!S_ISDIR (st.st_mode))
+        continue;
 
-          if (!flatpak_cp_a (child, locale_subdir, NULL,
-                             FLATPAK_CP_FLAGS_MERGE | FLATPAK_CP_FLAGS_MOVE,
-                             NULL, NULL, error))
-            return FALSE;
+      g_ptr_array_add (names, g_strdup (dent->d_name));
+    }
 
-          target = g_build_filename ("../../share/runtime/locale", relative, NULL);
+  *out_names = g_steal_pointer (&names);
+  return TRUE;
+}
 
-          if (!g_file_make_symbolic_link (child, target,
-                                          NULL, error))
-            return FALSE;
+static gboolean
+migrate_lc_dir (int          src_dfd,
+                const char  *lc_name,
+                int          dst_dfd,
+                GError     **error)
+{
+  glnx_autofd int lc_src_dfd = -1;
+  glnx_autofd int lc_dst_dfd = -1;
+  g_auto(GLnxDirFdIterator) iter = { 0, };
+  g_autoptr(GPtrArray) files = g_ptr_array_new_with_free_func (locale_file_free);
+  struct stat dir_st;
+  struct dirent *dent;
+
+  if (!glnx_opendirat (src_dfd, lc_name, FALSE, &lc_src_dfd, error))
+    return FALSE;
+
+  if (!glnx_ensure_dir (dst_dfd, lc_name, 0755, error))
+    return FALSE;
+
+  lc_dst_dfd = openat (dst_dfd, lc_name,
+                       O_DIRECTORY | O_NOFOLLOW | O_CLOEXEC);
+  if (lc_dst_dfd < 0)
+    return glnx_throw_errno_prefix (error, "openat LC dir %s", lc_name);
+
+  if (!glnx_dirfd_iterator_init_at (lc_src_dfd, ".", FALSE, &iter, error))
+    return FALSE;
+
+  if (fstat (iter.fd, &dir_st) < 0)
+    return glnx_throw_errno_prefix (error, "fstat LC dir %s", lc_name);
+
+  while (TRUE)
+    {
+      glnx_autofd int opath_fd = -1;
+      struct stat st;
+      LocaleFile *lf;
+
+      if (!glnx_dirfd_iterator_next_dent_ensure_dtype (&iter, &dent, NULL, error))
+        return FALSE;
+
+      if (dent == NULL)
+        break;
 
+      if (dent->d_type != DT_REG)
+        continue;
+
+      opath_fd = openat (iter.fd, dent->d_name,
+                         O_PATH | O_NOFOLLOW | O_CLOEXEC);
+      if (opath_fd < 0)
+        {
+          if (G_IN_SET (errno, ENOENT, EACCES))
+            continue;
+          return glnx_throw_errno_prefix (error, "openat %s", dent->d_name);
         }
+
+      if (fstat (opath_fd, &st) < 0)
+        return glnx_throw_errno_prefix (error, "fstat %s", dent->d_name);
+
+      if (!S_ISREG (st.st_mode))
+        continue;
+
+      lf = g_new0 (LocaleFile, 1);
+      lf->opath_fd = g_steal_fd (&opath_fd);
+      lf->name = g_strdup (dent->d_name);
+      g_ptr_array_add (files, lf);
+    }
+
+  for (size_t i = 0; i < files->len; i++)
+    {
+      LocaleFile *lf = g_ptr_array_index (files, i);
+      glnx_autofd int src_fd = -1;
+      glnx_autofd int dst_fd = -1;
+
+      src_fd = glnx_fd_reopen (lf->opath_fd, O_RDONLY, error);
+      if (src_fd < 0)
+        return FALSE;
+
+      dst_fd = openat (lc_dst_dfd, lf->name,
+                       O_WRONLY | O_CREAT | O_TRUNC | O_NOFOLLOW | O_CLOEXEC, 0644);
+      if (dst_fd < 0)
+        return glnx_throw_errno_prefix (error, "openat dest %s", lf->name);
+
+      if (glnx_regfile_copy_bytes (src_fd, dst_fd, -1) < 0)
+        return glnx_throw_errno_prefix (error, "copying locale file %s", lf->name);
+
+      if (unlinkat (lc_src_dfd, lf->name, 0) < 0)
+        return glnx_throw_errno_prefix (error, "unlinkat %s", lf->name);
+    }
+
+  if (unlinkat (src_dfd, lc_name, AT_REMOVEDIR) < 0)
+    {
+      if (errno == ENOTEMPTY)
+        return TRUE;
+      return glnx_throw_errno_prefix (error, "unlinkat LC dir %s", lc_name);
+    }
+
+  return TRUE;
+}
+
+static gboolean
+migrate_lang_dir (int          source_dfd,
+                  const char  *lang_name,
+                  int          separate_dfd,
+                  const char  *subdir,
+                  GError     **error)
+{
+  glnx_autofd int child_dfd = -1;
+  glnx_autofd int locale_subdir_dfd = -1;
+  g_autofree char *language = g_strdup (lang_name);
+  g_autofree char *target = NULL;
+  g_autoptr(GPtrArray) lc_dirs = NULL;
+  char *c;
+
+  c = strchr (language, '@');
+  if (c != NULL)
+    *c = 0;
+  c = strchr (language, '_');
+  if (c != NULL)
+    *c = 0;
+  c = strchr (language, '.');
+  if (c != NULL)
+    *c = 0;
+
+  const char *components[] = { language, subdir, lang_name, NULL };
+
+  if (!builder_ensure_dirs_at (separate_dfd, components, &locale_subdir_dfd, error))
+    return FALSE;
+
+  if (!glnx_opendirat (source_dfd, lang_name, FALSE, &child_dfd, error))
+    return FALSE;
+
+  if (!collect_dir_names (child_dfd, &lc_dirs, error))
+    return FALSE;
+
+  for (size_t i = 0; i < lc_dirs->len; i++)
+    {
+      if (!migrate_lc_dir (child_dfd, g_ptr_array_index (lc_dirs, i),
+                           locale_subdir_dfd, error))
+        return FALSE;
+    }
+
+  {
+    g_auto(GLnxDirFdIterator) file_iter = { 0, };
+    g_autoptr(GPtrArray) direct_files = g_ptr_array_new_with_free_func (locale_file_free);
+    struct dirent *fdent;
+
+    if (!glnx_dirfd_iterator_init_at (child_dfd, ".", FALSE, &file_iter, error))
+      return FALSE;
+
+    while (TRUE)
+      {
+        glnx_autofd int opath_fd = -1;
+        struct stat st;
+        LocaleFile *lf;
+
+        if (!glnx_dirfd_iterator_next_dent_ensure_dtype (&file_iter, &fdent, NULL, error))
+          return FALSE;
+
+        if (fdent == NULL)
+          break;
+
+        if (fdent->d_type != DT_REG)
+          continue;
+
+        opath_fd = openat (file_iter.fd, fdent->d_name,
+                           O_PATH | O_NOFOLLOW | O_CLOEXEC);
+        if (opath_fd < 0)
+          {
+            if (G_IN_SET (errno, ENOENT, EACCES))
+              continue;
+            return glnx_throw_errno_prefix (error, "openat %s", fdent->d_name);
+          }
+
+        if (fstat (opath_fd, &st) < 0)
+          return glnx_throw_errno_prefix (error, "fstat %s", fdent->d_name);
+
+        if (!S_ISREG (st.st_mode))
+          continue;
+
+        lf = g_new0 (LocaleFile, 1);
+        lf->opath_fd = g_steal_fd (&opath_fd);
+        lf->name = g_strdup (fdent->d_name);
+        g_ptr_array_add (direct_files, lf);
+      }
+
+    for (size_t i = 0; i < direct_files->len; i++)
+      {
+        LocaleFile *lf = g_ptr_array_index (direct_files, i);
+        glnx_autofd int src_fd = -1;
+        glnx_autofd int dst_fd = -1;
+
+        src_fd = glnx_fd_reopen (lf->opath_fd, O_RDONLY, error);
+        if (src_fd < 0)
+          return FALSE;
+
+        dst_fd = openat (locale_subdir_dfd, lf->name,
+                         O_WRONLY | O_CREAT | O_TRUNC | O_NOFOLLOW | O_CLOEXEC, 0644);
+        if (dst_fd < 0)
+          return glnx_throw_errno_prefix (error, "openat dest %s", lf->name);
+
+        if (glnx_regfile_copy_bytes (src_fd, dst_fd, -1) < 0)
+          return glnx_throw_errno_prefix (error, "copying locale file %s", lf->name);
+
+        if (unlinkat (child_dfd, lf->name, 0) < 0)
+          return glnx_throw_errno_prefix (error, "unlinkat %s", lf->name);
+      }
+  }
+
+  target = g_build_filename ("../../share/runtime/locale",
+                             language, subdir, lang_name, NULL);
+
+  if (unlinkat (source_dfd, lang_name, AT_REMOVEDIR) < 0)
+    {
+      if (errno == ENOTEMPTY)
+        return TRUE;
+      return glnx_throw_errno_prefix (error, "unlinkat LC dir %s", lang_name);
     }
 
-  if (temp_error != NULL)
+  if (symlinkat (target, source_dfd, lang_name) < 0)
+    return glnx_throw_errno_prefix (error, "symlinkat %s", lang_name);
+
+  return TRUE;
+}
+
+static gboolean
+migrate_locale_dir (int         root_dfd,
+                    const char *source_rel,
+                    int         separate_dfd,
+                    const char *subdir,
+                    GError    **error)
+{
+  glnx_autofd int chase_fd = -1;
+  glnx_autofd int source_dfd = -1;
+  g_autoptr(GPtrArray) lang_dirs = NULL;
+
+  chase_fd = glnx_chaseat (root_dfd, source_rel,
+                           GLNX_CHASE_RESOLVE_BENEATH | GLNX_CHASE_MUST_BE_DIRECTORY,
+                           error);
+  if (chase_fd < 0)
     {
-      g_propagate_error (error, temp_error);
+      if (g_error_matches (*error, G_IO_ERROR, G_IO_ERROR_NOT_FOUND) ||
+          g_error_matches (*error, G_IO_ERROR, G_IO_ERROR_NOT_DIRECTORY))
+        {
+          g_clear_error (error);
+          return TRUE;
+        }
       return FALSE;
     }
 
+  source_dfd = openat (chase_fd, ".", O_RDONLY | O_DIRECTORY | O_NOFOLLOW | O_CLOEXEC);
+  if (source_dfd < 0)
+    return glnx_throw_errno_prefix (error, "failed to reopen locale dir %s", source_rel);
+
+  if (!collect_dir_names (source_dfd, &lang_dirs, error))
+    return FALSE;
+
+  for (size_t i = 0; i < lang_dirs->len; i++)
+    {
+      const char *lang_name = g_ptr_array_index (lang_dirs, i);
+      g_autofree char *language = g_strdup (lang_name);
+      char *c;
+
+      c = strchr (language, '@');
+      if (c != NULL)
+        *c = 0;
+      c = strchr (language, '_');
+      if (c != NULL)
+        *c = 0;
+      c = strchr (language, '.');
+      if (c != NULL)
+        *c = 0;
+
+      /* We ship english and C locales always */
+      if (strcmp (language, "C") == 0 ||
+          strcmp (language, "en") == 0)
+        continue;
+
+      if (!migrate_lang_dir (source_dfd, lang_name, separate_dfd, subdir, error))
+        return FALSE;
+    }
+
   return TRUE;
 }
 
@@ -395,18 +669,22 @@ gboolean
 builder_migrate_locale_dirs (GFile   *root_dir,
                              GError **error)
 {
-  g_autoptr(GFile) separate_dir = NULL;
-  g_autoptr(GFile) lib_locale_dir = NULL;
-  g_autoptr(GFile) share_locale_dir = NULL;
+  glnx_autofd int root_dfd = -1;
+  glnx_autofd int separate_dfd = -1;
+  const char *separate_components[] = { "share", "runtime", "locale", NULL };
 
-  lib_locale_dir = g_file_resolve_relative_path (root_dir, "lib/locale");
-  share_locale_dir = g_file_resolve_relative_path (root_dir, "share/locale");
-  separate_dir = g_file_resolve_relative_path (root_dir, "share/runtime/locale");
+  if (!glnx_opendirat (AT_FDCWD,
+                       flatpak_file_get_path_cached (root_dir),
+                       FALSE, &root_dfd, error))
+    return FALSE;
+
+  if (!builder_ensure_dirs_at (root_dfd, separate_components, &separate_dfd, error))
+    return FALSE;
 
-  if (!migrate_locale_dir (lib_locale_dir, separate_dir, "lib", error))
+  if (!migrate_locale_dir (root_dfd, "lib/locale", separate_dfd, "lib", error))
     return FALSE;
 
-  if (!migrate_locale_dir (share_locale_dir, separate_dir, "share", error))
+  if (!migrate_locale_dir (root_dfd, "share/locale", separate_dfd, "share", error))
     return FALSE;
 
   return TRUE;
diff --git a/tests/meson.build b/tests/meson.build
index eda0e2d1..30c3a198 100644
--- a/tests/meson.build
+++ b/tests/meson.build
@@ -16,6 +16,7 @@ test_names = [
   'test-builder-cleanup',
   'test-builder-licence-paths',
   'test-builder-src-date-epoch',
+  'test-builder-locale-migration',
 ]
 
 tap_test = find_program(
diff --git a/tests/test-builder-locale-migration.sh b/tests/test-builder-locale-migration.sh
new file mode 100755
index 00000000..d832df15
--- /dev/null
+++ b/tests/test-builder-locale-migration.sh
@@ -0,0 +1,186 @@
+#!/bin/bash
+#
+# Copyright (C) 2026 Boudhayan Bhattacharya <bbhtt@bbhtt.in>
+#
+# This library is free software; you can redistribute it and/or
+# modify it under the terms of the GNU Lesser General Public
+# License as published by the Free Software Foundation; either
+# version 2 of the License, or (at your option) any later version.
+#
+# This library is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+# Lesser General Public License for more details.
+#
+# You should have received a copy of the GNU Lesser General Public
+# License along with this library; if not, write to the
+# Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+# Boston, MA 02111-1307, USA.
+
+set -euo pipefail
+
+. $(dirname $0)/libtest.sh
+
+skip_without_fuse
+
+echo "1..3"
+
+setup_repo
+install_repo
+setup_sdk_repo
+install_sdk_repo
+
+cd "$TEST_DATA_DIR"
+
+run_build () {
+    local manifest=$1
+    ${FLATPAK_BUILDER} --force-clean appdir "$manifest" >&2
+}
+
+cat > test-locale-migration.json <<'EOF'
+{
+    "app-id": "org.test.locale_migration",
+    "runtime": "org.test.Platform",
+    "sdk": "org.test.Sdk",
+    "modules": [{
+        "name": "test",
+        "buildsystem": "simple",
+        "build-commands": [
+            "mkdir -p /app/share/locale/de/LC_MESSAGES",
+            "echo 'de translation' > /app/share/locale/de/LC_MESSAGES/test.mo",
+            "mkdir -p /app/share/locale/C/LC_MESSAGES",
+            "echo 'C locale' > /app/share/locale/C/LC_MESSAGES/test.mo",
+            "mkdir -p /app/share/locale/en/LC_MESSAGES",
+            "echo 'en locale' > /app/share/locale/en/LC_MESSAGES/test.mo",
+            "mkdir -p /app/lib/locale/ru/LC_MESSAGES",
+            "echo 'ru translation' > /app/lib/locale/ru/LC_MESSAGES/test.mo",
+            "mkdir -p /app/share/locale/sr@latin/LC_MESSAGES",
+            "echo 'sr latin' > /app/share/locale/sr@latin/LC_MESSAGES/test.mo",
+            "mkdir -p /app/share/locale/pt_BR/LC_MESSAGES",
+            "echo 'pt_BR translation' > /app/share/locale/pt_BR/LC_MESSAGES/test.mo",
+            "mkdir -p /app/share/locale/de.utf8/LC_MESSAGES",
+            "echo 'de utf8' > /app/share/locale/de.utf8/LC_MESSAGES/test.mo",
+            "mkdir -p /app/share/locale/ko/LC_MESSAGES",
+            "echo 'app1' > /app/share/locale/ko/LC_MESSAGES/app1.mo",
+            "echo 'app2' > /app/share/locale/ko/LC_MESSAGES/app2.mo",
+            "mkdir -p /app/share/locale/es/LC_MESSAGES",
+            "echo 'es share' > /app/share/locale/es/LC_MESSAGES/test.mo",
+            "mkdir -p /app/lib/locale/es/LC_CTYPE",
+            "echo 'es lib' > /app/lib/locale/es/LC_CTYPE/test.mo",
+            "mkdir -p /app/share/locale/sv"
+        ]
+    }]
+}
+EOF
+
+run_build test-locale-migration.json
+
+# share/locale is migrated to share/runtime/locale/<lang>
+assert_has_symlink appdir/files/share/locale/de
+assert_symlink_has_content appdir/files/share/locale/de 'share/runtime/locale/de'
+assert_has_file appdir/files/share/runtime/locale/de/share/de/LC_MESSAGES/test.mo
+assert_file_has_content appdir/files/share/runtime/locale/de/share/de/LC_MESSAGES/test.mo 'de translation'
+
+# lib/locale is migrated to share/runtime/locale/<lang>
+assert_has_symlink appdir/files/lib/locale/ru
+assert_symlink_has_content appdir/files/lib/locale/ru 'share/runtime/locale/ru'
+assert_has_file appdir/files/share/runtime/locale/ru/lib/ru/LC_MESSAGES/test.mo
+assert_file_has_content appdir/files/share/runtime/locale/ru/lib/ru/LC_MESSAGES/test.mo 'ru translation'
+
+# C and en locales are not migrated
+assert_has_dir appdir/files/share/locale/C
+assert_has_file appdir/files/share/locale/C/LC_MESSAGES/test.mo
+assert_file_has_content appdir/files/share/locale/C/LC_MESSAGES/test.mo 'C locale'
+
+assert_has_dir appdir/files/share/locale/en
+assert_has_file appdir/files/share/locale/en/LC_MESSAGES/test.mo
+assert_file_has_content appdir/files/share/locale/en/LC_MESSAGES/test.mo 'en locale'
+
+# '@' stripped: sr@latin -> sr
+assert_has_symlink appdir/files/share/locale/sr@latin
+assert_has_file appdir/files/share/runtime/locale/sr/share/sr@latin/LC_MESSAGES/test.mo
+assert_file_has_content appdir/files/share/runtime/locale/sr/share/sr@latin/LC_MESSAGES/test.mo 'sr latin'
+
+# '_' stripped: pt_BR -> pt
+assert_has_symlink appdir/files/share/locale/pt_BR
+assert_symlink_has_content appdir/files/share/locale/pt_BR 'share/runtime/locale/pt'
+assert_has_file appdir/files/share/runtime/locale/pt/share/pt_BR/LC_MESSAGES/test.mo
+assert_file_has_content appdir/files/share/runtime/locale/pt/share/pt_BR/LC_MESSAGES/test.mo 'pt_BR translation'
+
+# '.' stripped: de.utf8 -> de
+assert_has_symlink appdir/files/share/locale/de.utf8
+assert_has_file appdir/files/share/runtime/locale/de/share/de.utf8/LC_MESSAGES/test.mo
+assert_file_has_content appdir/files/share/runtime/locale/de/share/de.utf8/LC_MESSAGES/test.mo 'de utf8'
+
+# multiple files in a single locale dir are migrated
+assert_has_symlink appdir/files/share/locale/ko
+assert_has_file appdir/files/share/runtime/locale/ko/share/ko/LC_MESSAGES/app1.mo
+assert_file_has_content appdir/files/share/runtime/locale/ko/share/ko/LC_MESSAGES/app1.mo 'app1'
+assert_has_file appdir/files/share/runtime/locale/ko/share/ko/LC_MESSAGES/app2.mo
+assert_file_has_content appdir/files/share/runtime/locale/ko/share/ko/LC_MESSAGES/app2.mo 'app2'
+
+# same language in share/locale and lib/locale is merged
+assert_has_symlink appdir/files/share/locale/es
+assert_has_file appdir/files/share/runtime/locale/es/share/es/LC_MESSAGES/test.mo
+assert_file_has_content appdir/files/share/runtime/locale/es/share/es/LC_MESSAGES/test.mo 'es share'
+assert_has_symlink appdir/files/lib/locale/es
+assert_has_file appdir/files/share/runtime/locale/es/lib/es/LC_CTYPE/test.mo
+assert_file_has_content appdir/files/share/runtime/locale/es/lib/es/LC_CTYPE/test.mo 'es lib'
+
+# empty locale dir creates empty migration dir
+assert_has_dir appdir/files/share/locale/sv
+assert_has_dir appdir/files/share/runtime/locale/sv
+
+echo "ok locale dirs migrated"
+
+
+cat > test-locale-disabled.json <<'EOF'
+{
+    "app-id": "org.test.locale_migration_disabled",
+    "runtime": "org.test.Platform",
+    "sdk": "org.test.Sdk",
+    "separate-locales": false,
+    "modules": [{
+        "name": "test",
+        "buildsystem": "simple",
+        "build-commands": [
+            "mkdir -p /app/share/locale/de/LC_MESSAGES",
+            "echo 'de translation' > /app/share/locale/de/LC_MESSAGES/test.mo"
+        ]
+    }]
+}
+EOF
+
+run_build test-locale-disabled.json
+
+assert_has_dir appdir/files/share/locale/de
+assert_has_file appdir/files/share/locale/de/LC_MESSAGES/test.mo
+assert_file_has_content appdir/files/share/locale/de/LC_MESSAGES/test.mo 'de translation'
+assert_not_has_dir appdir/files/share/runtime/locale
+
+echo "ok locale dirs migration is disabled on separate-locales false"
+
+cat > test-locale-migration-runtime.json <<'EOF'
+{
+    "app-id": "org.test.locale_migration_runtime",
+    "runtime": "org.test.Platform",
+    "sdk": "org.test.Sdk",
+    "build-runtime": true,
+    "modules": [{
+        "name": "test",
+        "buildsystem": "simple",
+        "build-commands": [
+            "mkdir -p /usr/share/locale/pl/LC_MESSAGES",
+            "echo 'pl translation' > /usr/share/locale/pl/LC_MESSAGES/test.mo"
+        ]
+    }]
+}
+EOF
+
+run_build test-locale-migration-runtime.json
+
+assert_has_symlink appdir/usr/share/locale/pl
+assert_has_file appdir/usr/share/runtime/locale/pl/share/pl/LC_MESSAGES/test.mo
+assert_file_has_content appdir/usr/share/runtime/locale/pl/share/pl/LC_MESSAGES/test.mo 'pl translation'
+
+echo "ok locale dirs migration works with runtime"