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How to avoid negative time spans

Dr. Roland Kuhn

Dr. Roland Kuhn

CTO and co-founder at Actyx

The main advantage of an event-based system like Actyx is that you have a lot of flexibility on how to make even more use of your data when adding new use-cases. This is achieved by combining the event streams of existing apps with new apps and new business logic. One issue that frequently arises in these scenarios is that further use, for example in business intelligence tools, exposes a phenomenon that we simply call “negative time spans”.

In this article I explain all about the how and why — the main takeaway is that you should make really sure to use NTP on all nodes.

Pond 2.7.0 Released

Benjamin Sieffert, Wolfgang Werner

Distributed Systems Engineer, Developer Advocate

We're happy to announce we've released Pond version 2.7.0 on npm!

Prior to this version, the pond takes snapshots every 1024 events, provided the first event to include in the snapshot is older than an hour. This threshold can now be configured as Pond default and for individual fish; the default behavior matches the one in previous versions.

How do I know when someone else is ready?

Dr. Roland Kuhn

Dr. Roland Kuhn

CTO and co-founder at Actyx

Actyx builds on the local-first cooperation paradigm, where the autonomy of individual computing devices is of high importance: this is the foundation for creating a system that always works — as long as you have a running computer in your hand, that computer remains maximally useful.

Striving for this autonomy also poses some interesting questions: how do I know that someone else has received the information I just logged? Or the decision I just made? Working together requires two-way communication in many cases, which we explore in this article.

Pond 2.5.0 Released

Benjamin Sieffert

Benjamin Sieffert

Distributed Systems Engineer at Actyx

Today we are glad to announce the release of Pond version 2.5.0 on npm!

This release contains a whole new set of functions, which operate on events directly – no Fish required. Read on for a quick overview.

Snapshot management in Actyx Pond

Wolfgang Werner

Developer Advocate

In event-sourced systems, state snapshots are used to alleviate the costs of computing state from event streams. Snapshots are essential to keep processing overhead and latency in check when working with long-lived and/or high traffic models.

The Actyx Pond ships with reasonable defaults for creating and retaining snapshots. However, in certain cases, snapshots may grow too large. This post outlines how to segment state and compress snapshots to avoid this.