What it is

pump.io is a social server and stream server written in JavaScript for Node.js, and it lives in the open-source ActivityStreams and social networking ecosystem. The project provides an ActivityStreams API, uses activitystrea.ms JSON as the main data and command format, and includes a web interface. Its documented purpose is to let a person post something and have followers see it, while also exposing social data in a machine-readable form.

The concrete problem it solves is the need for a reusable social layer inside an application or experiment. Instead of building a stream model from scratch, a project can use pump.io to represent posts, follow relationships, lists, and other activity-stream content. The README states that it is useful for activity stream functionality in an existing app and for experimenting with social software.

Key capabilities

• The server exposes an ActivityStreams API, with the interface defined in the API.md file.
• It uses activitystrea.ms JSON as the main data and command format for social objects and operations.
• It supports posting short or long text, bookmarks, images, video, audio, events, and geo checkins.
• It supports following friends and creating lists of people.
• It includes a web UI for interacting with the stream server.
• The topic list indicates decentralization and federation as project concerns.
• It is distributed as an Apache-2.0 licensed Node.js package named pump.io.

Who uses it and how

• Developers use pump.io as a backend when they need activity stream functionality for an existing app.
• Self-hosters use it as a social server where users post items and followers see those items.
• Experimenters use the web UI and ActivityStreams format to study social software behavior.
• Community operators may use the project when they care about decentralization and federation, as indicated by the topics.
• Client developers can build against the documented API and the activitystrea.ms JSON data format.

Getting started

The README points to the pump.io npm package and to ReadTheDocs for technical documentation, so the typical path is to install the Node.js package and follow the documented setup instructions. The README also links to the project homepage and GitHub wiki for policies and further information.

When to use it — and when not to

Use pump.io when you need an open-source ActivityStreams social server for a custom application, a self-hosted stream, or an experiment. Do not choose it if you expect a managed hosted service, because the provided facts mention no hosted option. A self-hoster must operate the Node.js service and may need to account for 679 open issues, missing contributor metadata, and operational requirements that are not specified in the README excerpt.