diff --git a/src/libostree/ostree-deployment-private.h b/src/libostree/ostree-deployment-private.h
index ad77317d79..000c0bbc8d 100644
--- a/src/libostree/ostree-deployment-private.h
+++ b/src/libostree/ostree-deployment-private.h
@@ -47,6 +47,7 @@ struct _OstreeDeployment
   char *csum;
   int deployserial;
   char *bootcsum;
+  char **additional_initrds;
   int bootserial;
   OstreeBootconfigParser *bootconfig;
   GKeyFile *origin;
@@ -56,4 +57,9 @@ struct _OstreeDeployment
 
 void _ostree_deployment_set_bootcsum (OstreeDeployment *self, const char *bootcsum);
 
+void _ostree_deployment_set_additional_initrds (OstreeDeployment *self,
+                                                char **additional_initrds);
+char**
+_ostree_deployment_get_additional_initrds (OstreeDeployment *self);
+
 G_END_DECLS
diff --git a/src/libostree/ostree-deployment.c b/src/libostree/ostree-deployment.c
index 70e1bc4928..6de1f0f43b 100644
--- a/src/libostree/ostree-deployment.c
+++ b/src/libostree/ostree-deployment.c
@@ -158,6 +158,20 @@ _ostree_deployment_set_bootcsum (OstreeDeployment *self,
   self->bootcsum = g_strdup (bootcsum);
 }
 
+void
+_ostree_deployment_set_additional_initrds (OstreeDeployment *self,
+                                           char            **additional_initrds)
+{
+  g_strfreev (self->additional_initrds);
+  self->additional_initrds = g_strdupv (additional_initrds);
+}
+
+char**
+_ostree_deployment_get_additional_initrds (OstreeDeployment *self)
+{
+  return self->additional_initrds;
+}
+
 /**
  * ostree_deployment_clone:
  * @self: Deployment
@@ -238,6 +252,7 @@ ostree_deployment_finalize (GObject *object)
   g_free (self->bootcsum);
   g_clear_object (&self->bootconfig);
   g_clear_pointer (&self->origin, g_key_file_unref);
+  g_strfreev (self->additional_initrds);
 
   G_OBJECT_CLASS (ostree_deployment_parent_class)->finalize (object);
 }
diff --git a/src/libostree/ostree-sysroot-cleanup.c b/src/libostree/ostree-sysroot-cleanup.c
index ffad413080..b4a3b4e3d2 100644
--- a/src/libostree/ostree-sysroot-cleanup.c
+++ b/src/libostree/ostree-sysroot-cleanup.c
@@ -298,6 +298,8 @@ cleanup_old_deployments (OstreeSysroot       *self,
     g_hash_table_new_full (g_str_hash, g_str_equal, g_free, NULL);
   g_autoptr(GHashTable) active_boot_checksums =
     g_hash_table_new_full (g_str_hash, g_str_equal, g_free, NULL);
+  g_autoptr(GHashTable) active_additional_initrds =
+    g_hash_table_new (g_str_hash, g_str_equal); /* borrows from deployment's bootconfig */
   for (guint i = 0; i < self->deployments->len; i++)
     {
       OstreeDeployment *deployment = self->deployments->pdata[i];
@@ -306,6 +308,11 @@ cleanup_old_deployments (OstreeSysroot       *self,
       /* Transfer ownership */
       g_hash_table_replace (active_deployment_dirs, deployment_path, deployment_path);
       g_hash_table_replace (active_boot_checksums, bootcsum, bootcsum);
+
+      OstreeBootconfigParser *bootconfig = ostree_deployment_get_bootconfig (deployment);
+      GPtrArray *initrds = ostree_bootconfig_parser_get_additional_initrds (bootconfig);
+      for (guint i = 0; i < initrds->len; i++)
+        g_hash_table_add (active_additional_initrds, (char*)glnx_basename (initrds->pdata[i]));
     }
 
   /* Find all deployment directories, both active and inactive */
@@ -349,6 +356,42 @@ cleanup_old_deployments (OstreeSysroot       *self,
         return FALSE;
     }
 
+  /* Clean up additional initrds */
+  glnx_autofd int overlays_dfd =
+    glnx_opendirat_with_errno (self->sysroot_fd, _OSTREE_SYSROOT_INITRAMFS_OVERLAYS, FALSE);
+  if (overlays_dfd < 0)
+    {
+      if (errno != ENOENT)
+        return glnx_throw_errno_prefix (error, "opendirat(overlays)");
+    }
+  else
+    {
+      g_autoptr(GPtrArray) initrds_to_delete = g_ptr_array_new_with_free_func (g_free);
+      g_auto(GLnxDirFdIterator) dfd_iter = { 0, };
+      if (!glnx_dirfd_iterator_init_at (overlays_dfd, ".", TRUE, &dfd_iter, error))
+        return FALSE;
+      while (TRUE)
+        {
+          struct dirent *dent;
+          if (!glnx_dirfd_iterator_next_dent_ensure_dtype (&dfd_iter, &dent, cancellable, error))
+            return FALSE;
+          if (dent == NULL)
+            break;
+
+          /* there shouldn't be other file types there, but let's be conservative */
+          if (dent->d_type != DT_REG)
+            continue;
+
+          if (!g_hash_table_lookup (active_additional_initrds, dent->d_name))
+            g_ptr_array_add (initrds_to_delete, g_strdup (dent->d_name));
+        }
+      for (guint i = 0; i < initrds_to_delete->len; i++)
+        {
+          if (!ot_ensure_unlinked_at (overlays_dfd, initrds_to_delete->pdata[i], error))
+            return FALSE;
+        }
+    }
+
   return TRUE;
 }
 
diff --git a/src/libostree/ostree-sysroot-deploy.c b/src/libostree/ostree-sysroot-deploy.c
index 0a5b5001ca..e35b31bb8e 100644
--- a/src/libostree/ostree-sysroot-deploy.c
+++ b/src/libostree/ostree-sysroot-deploy.c
@@ -1854,6 +1854,48 @@ install_deployment_kernel (OstreeSysroot   *sysroot,
         }
     }
 
+  g_autoptr(GPtrArray) additional_initrds = NULL;
+  for (char **it = _ostree_deployment_get_additional_initrds (deployment); it && *it; it++)
+    {
+      char *initrd = *it;
+
+      /* Additional initrds are not part of the bootcsum dir; they're not part of the tree
+       * proper. Instead they're in /boot/ostree/initramfs-overlays/ named by their csum.
+       * Doing it this way allows sharing the same bootcsum dir for multiple deployments
+       * with the only change being in additional initrds. */
+
+      g_autofree char *checksum =
+        ot_checksum_file_at (AT_FDCWD, initrd, G_CHECKSUM_SHA256, cancellable, error);
+      if (checksum == NULL)
+        return glnx_prefix_error (error, "Checksumming %s", initrd);
+
+      g_autofree char *destpath =
+        g_strdup_printf ("/" _OSTREE_SYSROOT_BOOT_INITRAMFS_OVERLAYS "/%s.img", checksum);
+      const char *rel_destpath = destpath + 1;
+
+      /* allocate an array and only create the dir if we actually have initrds */
+      if (additional_initrds == NULL)
+        {
+          additional_initrds = g_ptr_array_new_with_free_func (g_free);
+
+          const char *parent = dirname (strdupa (rel_destpath));
+          if (!glnx_shutil_mkdir_p_at (boot_dfd, parent, 0755, cancellable, error))
+            return FALSE;
+        }
+
+      if (!glnx_fstatat_allow_noent (boot_dfd, rel_destpath, &stbuf, 0, error))
+        return FALSE;
+
+      if (errno == ENOENT)
+        {
+          if (!install_into_boot (repo, sepolicy, AT_FDCWD, initrd, boot_dfd, rel_destpath,
+                                  cancellable, error))
+            return FALSE;
+        }
+
+      g_ptr_array_add (additional_initrds, g_steal_pointer (&destpath));
+    }
+
   g_autofree char *contents = NULL;
   if (!glnx_fstatat_allow_noent (deployment_dfd, "usr/lib/os-release", &stbuf, 0, error))
     return FALSE;
@@ -1933,6 +1975,12 @@ install_deployment_kernel (OstreeSysroot   *sysroot,
       g_autofree char * initrd_boot_relpath =
         g_strconcat ("/", bootcsumdir, "/", kernel_layout->initramfs_namever, NULL);
       ostree_bootconfig_parser_set (bootconfig, "initrd", initrd_boot_relpath);
+
+      if (additional_initrds)
+        {
+          for (guint i = 0; i < additional_initrds->len; i++)
+            ostree_bootconfig_parser_add_initrd (bootconfig, additional_initrds->pdata[i]);
+        }
     }
   else
     {
@@ -2711,6 +2759,7 @@ sysroot_initialize_deployment (OstreeSysroot     *self,
 
   _ostree_deployment_set_bootcsum (new_deployment, kernel_layout->bootcsum);
   _ostree_deployment_set_bootconfig_from_kargs (new_deployment, opts->override_kernel_argv);
+  _ostree_deployment_set_additional_initrds (new_deployment, opts->additional_initrds);
 
   if (!prepare_deployment_etc (self, repo, new_deployment, deployment_dfd,
                                cancellable, error))
@@ -3111,6 +3160,9 @@ ostree_sysroot_stage_tree_with_options (OstreeSysroot     *self,
   if (opts->override_kernel_argv)
     g_variant_builder_add (builder, "{sv}", "kargs",
                            g_variant_new_strv ((const char *const*)opts->override_kernel_argv, -1));
+  if (opts->additional_initrds)
+    g_variant_builder_add (builder, "{sv}", "additional-initrds",
+                           g_variant_new_strv ((const char *const*)opts->additional_initrds, -1));
 
   const char *parent = dirname (strdupa (_OSTREE_SYSROOT_RUNSTATE_STAGED));
   if (!glnx_shutil_mkdir_p_at (AT_FDCWD, parent, 0755, cancellable, error))
diff --git a/src/libostree/ostree-sysroot-private.h b/src/libostree/ostree-sysroot-private.h
index fa1e53361c..a3f7ce68a4 100644
--- a/src/libostree/ostree-sysroot-private.h
+++ b/src/libostree/ostree-sysroot-private.h
@@ -87,6 +87,9 @@ struct OstreeSysroot {
 #define _OSTREE_SYSROOT_DEPLOYMENT_RUNSTATE_FLAG_DEVELOPMENT "unlocked-development"
 #define _OSTREE_SYSROOT_DEPLOYMENT_RUNSTATE_FLAG_TRANSIENT "unlocked-transient"
 
+#define _OSTREE_SYSROOT_BOOT_INITRAMFS_OVERLAYS "ostree/initramfs-overlays"
+#define _OSTREE_SYSROOT_INITRAMFS_OVERLAYS "boot/" _OSTREE_SYSROOT_BOOT_INITRAMFS_OVERLAYS
+
 gboolean
 _ostree_sysroot_ensure_writable (OstreeSysroot      *self,
                                  GError            **error);
diff --git a/src/libostree/ostree-sysroot.c b/src/libostree/ostree-sysroot.c
index b211fea723..9c7b41522a 100644
--- a/src/libostree/ostree-sysroot.c
+++ b/src/libostree/ostree-sysroot.c
@@ -966,8 +966,10 @@ _ostree_sysroot_reload_staged (OstreeSysroot *self,
       /* Parse it */
       g_autoptr(GVariant) target = NULL;
       g_autofree char **kargs = NULL;
+      g_autofree char **additional_initrds = NULL;
       g_variant_dict_lookup (staged_deployment_dict, "target", "@a{sv}", &target);
       g_variant_dict_lookup (staged_deployment_dict, "kargs", "^a&s", &kargs);
+      g_variant_dict_lookup (staged_deployment_dict, "additional-initrds", "^a&s", &additional_initrds);
       if (target)
         {
           g_autoptr(OstreeDeployment) staged =
@@ -979,6 +981,8 @@ _ostree_sysroot_reload_staged (OstreeSysroot *self,
           if (!load_origin (self, staged, NULL, error))
             return FALSE;
 
+          _ostree_deployment_set_additional_initrds (staged, additional_initrds);
+
           self->staged_deployment = g_steal_pointer (&staged);
           self->staged_deployment_data = g_steal_pointer (&staged_deployment_data);
           /* We set this flag for ostree_deployment_is_staged() because that API
diff --git a/src/libostree/ostree-sysroot.h b/src/libostree/ostree-sysroot.h
index 45d6d63cc4..3092b60bd0 100644
--- a/src/libostree/ostree-sysroot.h
+++ b/src/libostree/ostree-sysroot.h
@@ -190,7 +190,8 @@ typedef struct {
   gboolean unused_bools[8];
   int unused_ints[8];
   char **override_kernel_argv;
-  gpointer unused_ptrs[7];
+  char **additional_initrds;
+  gpointer unused_ptrs[6];
 } OstreeSysrootDeployTreeOpts;
 
 _OSTREE_PUBLIC