     }
     
     private func plugin(forIdentifier id: DependencyID) -> Pluggable? {
-        let found = startedPlugins.filter { (plugin) -> Bool in
-            if plugin.identifier.lowercased() == id.lowercased() {
-                return true
-            }
-            return false
-        }
-        
-        if found.count > 1 {
-            assertionFailure("found more than one plugin with id \(id)!")
-        } else if found.count == 1 {
-            return found[0]
-        }
-        
-        return nil
+        return startedPluginsLookup[id.lowercased()]
     }
     
     private func start(plugin: Pluggable) {


@objc open class Supervisor: UIResponder {
    public private(set) var startedPlugins = [Pluggable]()
    public var navigator: SupervisorNavigator?
    
    private var proposedPlugins = [Pluggable]()

            
            plugin.startup(self)
            startedPlugins.append(plugin)
            let lowercasedIdentifier = plugin.identifier.lowercased()
            guard startedPluginsLookup[lowercasedIdentifier] == nil else {
                assertionFailure("tried to started more than one plugin with id \(plugin.identifier)!")
                return
            }
            startedPluginsLookup[plugin.identifier.lowercased()] = plugin
            print("started: \(plugin.identifier)")
        }
    }
