Overview

What is Nussknacker

Nussknacker is a low-code visual tool for domain experts to define and run real-time decisioning algorithms instead of implementing them in the code.

In all IT systems, no matter the domain, decisions are made all the time. Which offer should a customer get? Who should receive a marketing message? Does this device need servicing? Is this a fraud?

Algorithms for making such decisions can be implemented in the code. Especially if high performance or integration of data from many sources is needed. But those algorithms often change: we have a new product we want to promote or we learn that some strange activity is not really a fraud. That requires changes in the code that would have to be made by developers.

Instead, such decision algorithms can be run by Nussknacker, where business experts can define and change them, without the need to trouble IT.

Nussknacker can make those decisions by processing event streams or in a request-response model, providing horizontal scalability and high availability. That way it fits various use cases in microservice and/or event driven architectures.

Why Nussknacker

An essential part of Nussknacker is a visual design tool for decision algorithms. It allows not-so-technical users – analysts or business people – to define decision logic in an imperative, easy to follow and understand way. Once authored, with a click of a button, scenarios are deployed for execution. And can be changed and redeployed anytime there’s a need.

Nussknacker supports two processing modes: streaming and request-response. In streaming mode it uses Kafka as its primary interface: input streams of data and output streams of decisions. In request-response mode it exposes HTTP endpoints with OpenAPI definitions. And since input events or requests are often not enough to make a decision, Nussknacker can enrich them with data from databases and OpenAPI endpoints.

Nussknacker can be used with its own, lightweight, Kubernetes-based engine. It provides scalability and high availability, while being straightforward to set up and maintain. However, in advanced streaming use cases, when aggregations are needed, Nussknacker can execute decision scenarios on Flink – one of the most advanced platforms for stream processing. More detailed engines comparison can be found here.

Scenario authoring with Nussknacker