Akka - Build powerful reactive, concurrent, and distributed applications in Java and Scala
Envoy - Visitor registration that's changing how guests are greeted in companies around the world.
RxJS - Reactive Extensions for Javascript
The Receptionist - The Receptionost is a visitor managemnt solution that has visitor logging system to track visitor traffic.
Tokio - Application and Data, Languages & Frameworks, and Concurrency Frameworks
Teamgo - Create a safer workplace for your visitors and employees. Teamgo visitor management captures sign-ins, prints badges, sends arrival notifications and emergency alerts.