diff --git a/package.json b/package.json
index 4df7cc4..a6d810f 100644
--- a/package.json
+++ b/package.json
@@ -1,6 +1,6 @@
 {
 	"name": "fire-lib-js",
-	"version": "0.2.10",
+	"version": "0.2.11",
 	"author": "Sören Meier <info@soerenmeier.ch>",
 	"type": "module",
 	"scripts": {
diff --git a/src/util/nonconcurrent.js b/src/util/nonconcurrent.js
new file mode 100644
index 0000000..818fb0d
--- /dev/null
+++ b/src/util/nonconcurrent.js
@@ -0,0 +1,27 @@
+/// synchronisation point
+export default class NonConcurrent {
+	constructor() {
+		this.listeners = [];
+		this.running = false;
+	}
+
+	// returns an object where you need to call ready once done
+	async start() {
+		if (this.running) {
+			await new Promise(resolve => {
+				this.listeners.push(resolve);
+			});
+		}
+
+		this.running = true;
+
+		return {
+			ready: () => {
+				this.running = false;
+				const resolve = this.listeners.shift();
+				if (resolve)
+					resolve();
+			}
+		};
+	}
+}
\ No newline at end of file