diff --git a/package-lock.json b/package-lock.json
new file mode 100644
index 0000000..3c607f9
--- /dev/null
+++ b/package-lock.json
@@ -0,0 +1,26 @@
+{
+	"name": "@haxelib/tink_state",
+	"lockfileVersion": 3,
+	"requires": true,
+	"packages": {
+		"": {
+			"name": "@haxelib/tink_state",
+			"hasInstallScript": true,
+			"dependencies": {
+				"lix": "^15.10.1"
+			}
+		},
+		"node_modules/lix": {
+			"version": "15.12.1",
+			"resolved": "https://registry.npmjs.org/lix/-/lix-15.12.1.tgz",
+			"integrity": "sha512-8cYNMYttFY6Pl18jGspIQBvhUP7ScjBOaoV025K1oWrRMhNNBep2NsEimBQq0u/Bcq2q3K58LWH1nr50aej6DA==",
+			"hasInstallScript": true,
+			"bin": {
+				"haxe": "bin/haxeshim.js",
+				"haxelib": "bin/haxelibshim.js",
+				"lix": "bin/lix.js",
+				"neko": "bin/nekoshim.js"
+			}
+		}
+	}
+}
diff --git a/src/tink/state/Observable.hx b/src/tink/state/Observable.hx
index 732632d..090aa9d 100644
--- a/src/tink/state/Observable.hx
+++ b/src/tink/state/Observable.hx
@@ -77,8 +77,11 @@ abstract Observable<T>(ObservableObject<T>) from ObservableObject<T> to Observab
   public function combine<A, R>(that:Observable<A>, f:T->A->R):Observable<R>
     return Observable.auto(() -> f(value, that.value));
 
-  public function nextTime(?options:{ ?butNotNow: Bool, ?hires:Bool }, check:T->Bool):Future<T>
-    return getNext(options, v -> if (check(v)) Some(v) else None);
+  public function nextTime(?options:{ ?butNotNow: Bool, ?hires:Bool }, ?condition:T->Bool):Future<T>
+    return getNext(options,
+      if (condition == null) Some
+      else v -> if (condition(v)) Some(v) else None
+    );
 
   public function getNext<R>(?options:{ ?butNotNow: Bool, ?hires:Bool }, select:T->Option<R>):Future<R> {
     var ret = Future.trigger(),
@@ -360,4 +363,4 @@ class ObservableTools {
   static public function flatten<T>(o:Observable<Observable<T>>)
     return Observable.auto(() -> Observable.lift(o).value.value);
 
-}
\ No newline at end of file
+}
diff --git a/tests.hxml b/tests.hxml
index 705f647..26f6852 100644
--- a/tests.hxml
+++ b/tests.hxml
@@ -1,6 +1,7 @@
+-cp src
 -cp tests
 -D no-deprecation-warnings
 -lib tink_unittest
 -main RunTests
 
--lib deep_equal
\ No newline at end of file
+-lib deep_equal
diff --git a/tests/TestBasic.hx b/tests/TestBasic.hx
index 2b4ee10..8f23719 100644
--- a/tests/TestBasic.hx
+++ b/tests/TestBasic.hx
@@ -1,7 +1,7 @@
 package;
 
-import tink.state.Scheduler.direct;
 import tink.state.*;
+import tink.state.Scheduler.direct;
 
 using tink.CoreApi;
 
@@ -126,6 +126,11 @@ class TestBasic {
 
     asserts.assert(fired == 4);
 
+    await(o.nextTime({ hires: true, }));
+    set(0);
+
+    asserts.assert(fired == 5);
+
     return asserts.done();
   }
 
@@ -152,7 +157,7 @@ class TestBasic {
 
     return asserts.done();
   }
-  
+
   public function mapAsync() {
     final s = new State(0);
     final o:Observable<Int> = s;