return map(oldPlugins, plugin -> {
            XmlNode pluginConfiguration = plugin.getConfiguration();
            if (pluginConfiguration != null) {
                return plugin.withExecutions(map(
                        plugin.getExecutions(),
                        execution -> execution.withConfiguration(
                                XmlNode.merge(execution.getConfiguration(), pluginConfiguration))));

                while (execs.putIfAbsent(id, e.withId(id)) != null) {
                    id = e.getId() + "-" + (++i);
                }
            });
            Plugin merged = cur.withExecutions(execs.values());
            plugins.put(merged, merged);
        }
    }

    private static String getExecutionId(Plugin plugin, String goal) {
        Set<String> existingIds = plugin != null