diff --git a/common.c b/common.c
index da937a1..cf950c8 100644
--- a/common.c
+++ b/common.c
@@ -2074,6 +2074,7 @@ static void
 config_load (struct config *self, struct config_item *root)
 {
 	hard_assert (root->type == CONFIG_ITEM_OBJECT);
+	if (self->root)  config_item_destroy (self->root);
 	self->root = root;
 
 	struct str_map_iter iter;
diff --git a/degesch.c b/degesch.c
index 96d0dc1..f2a23c9 100644
--- a/degesch.c
+++ b/degesch.c
@@ -2017,7 +2017,7 @@ error:
 }
 
 static void
-serialize_configuration (struct app_context *ctx, struct str *output)
+serialize_configuration (struct config_item *root, struct str *output)
 {
 	str_append (output,
 		"# " PROGRAM_NAME " " PROGRAM_VERSION " configuration file\n"
@@ -2028,7 +2028,7 @@ serialize_configuration (struct app_context *ctx, struct str *output)
 		"# Everything is in UTF-8.  Any custom comments will be overwritten.\n"
 		"\n");
 
-	config_item_write (ctx->config.root, true, output);
+	config_item_write (root, true, output);
 }
 
 // --- Terminal output ---------------------------------------------------------
@@ -7110,9 +7110,9 @@ str_vector_sort (struct str_vector *self)
 
 static void
 dump_matching_options
-	(struct app_context *ctx, const char *mask, struct str_vector *output)
+	(struct config_item *root, const char *mask, struct str_vector *output)
 {
-	config_dump (ctx->config.root, output);
+	config_dump (root, output);
 	str_vector_sort (output);
 
 	// Filter out results by wildcard matching
@@ -7133,7 +7133,7 @@ save_configuration (struct app_context *ctx)
 {
 	struct str data;
 	str_init (&data);
-	serialize_configuration (ctx, &data);
+	serialize_configuration (ctx->config.root, &data);
 
 	struct error *e = NULL;
 	char *filename = write_configuration_file (&data, &e);
@@ -8379,7 +8379,7 @@ handle_command_set_assign_item (struct app_context *ctx,
 	{
 		struct str_vector tmp;
 		str_vector_init (&tmp);
-		dump_matching_options (ctx, key, &tmp);
+		dump_matching_options (ctx->config.root, key, &tmp);
 		log_global_status (ctx, "Option changed: #s", tmp.vector[0]);
 		str_vector_free (&tmp);
 	}
@@ -8436,7 +8436,7 @@ handle_command_set (struct handler_args *a)
 
 	struct str_vector all;
 	str_vector_init (&all);
-	dump_matching_options (ctx, option, &all);
+	dump_matching_options (ctx->config.root, option, &all);
 
 	bool result = true;
 	if (!all.len)
@@ -10781,8 +10781,6 @@ load_configuration (struct app_context *ctx)
 
 	if (root)
 	{
-		config_item_destroy (ctx->config.root);
-		ctx->config.root = NULL;
 		config_load (&ctx->config, root);
 		log_global_status (ctx, "Configuration loaded");
 	}
@@ -11206,6 +11204,71 @@ init_poller_events (struct app_context *ctx)
 
 #ifdef TESTING
 
+static void
+on_test_config_foo_change (struct config_item *item)
+{
+	*(bool *) item->user_data = item->value.boolean;
+}
+
+static struct config_schema g_config_test[] =
+{
+	{ .name      = "foo",
+	  .comment   = "baz",
+	  .type      = CONFIG_ITEM_BOOLEAN,
+	  .default_  = "off",
+	  .on_change = on_test_config_foo_change },
+	{ .name      = "bar",
+	  .type      = CONFIG_ITEM_INTEGER,
+	  .validate  = config_validate_nonnegative,
+	  .default_  = "1" },
+	{ .name      = "foobar",
+	  .type      = CONFIG_ITEM_STRING,
+	  .default_  = "\"qux\"" },
+	{}
+};
+
+static void
+test_config_load (struct config_item *subtree, void *user_data)
+{
+	config_schema_apply_to_object (g_config_test, subtree, user_data);
+}
+
+static void
+test_config (void)
+{
+	struct config config;
+	config_init (&config);
+
+	bool b = true;
+	config_register_module (&config, "top", test_config_load, &b);
+	config_load (&config, config_item_object ());
+	config_schema_call_changed (config.root);
+	hard_assert (b == false);
+
+	struct config_item *invalid = config_item_integer (-1);
+	hard_assert (!config_item_set_from (config_item_get (config.root,
+		"top.bar", NULL), invalid, NULL));
+	config_item_destroy (invalid);
+
+	struct str s;
+	str_init (&s);
+	serialize_configuration (config.root, &s);
+	config_load (&config, config_item_parse (s.str, s.len, false, NULL));
+	str_free (&s);
+
+	struct str_vector v;
+	str_vector_init (&v);
+	dump_matching_options (config.root, "*foo*", &v);
+	hard_assert (v.len == 2);
+	hard_assert (!strcmp (v.vector[0], "top.foo = off"));
+	hard_assert (!strcmp (v.vector[1], "top.foobar = \"qux\""));
+	str_vector_free (&v);
+
+	config_free (&config);
+}
+
+// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
+
 static void
 test_aliases (void)
 {
@@ -11223,18 +11286,16 @@ test_aliases (void)
 static void
 test_wrapping (void)
 {
-	struct str_vector v;
-	str_vector_init (&v);
-
 	static const char *message = " foo bar foobar fóóbárbáz";
 	static const char *split[] =
 		{ " foo", "bar", "foob", "ar", "fó", "ób", "árb", "áz" };
 
+	struct str_vector v;
+	str_vector_init (&v);
 	hard_assert (wrap_message (message, 4, &v, NULL));
 	hard_assert (v.len == N_ELEMENTS (split));
 	for (size_t i = 0; i < N_ELEMENTS (split); i++)
 		hard_assert (!strcmp (v.vector[i], split[i]));
-
 	str_vector_free (&v);
 }
 
@@ -11250,6 +11311,7 @@ main (int argc, char *argv[])
 {
 	struct test test;
 	test_init (&test, argc, argv);
+	test_add_simple (&test, "/config",      NULL, test_config);
 	test_add_simple (&test, "/aliases",     NULL, test_aliases);
 	test_add_simple (&test, "/wrapping",    NULL, test_wrapping);
 	test_add_simple (&test, "/utf8-prefix", NULL, test_utf8_prefix);