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    Comunica is a knowledge graph querying framework.
    This page provides more details about its goals and motivations.

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    Watch a Webinar recording to learn more about Comunica.

    Flexible querying of Linked Data

    Linked Data on the Web exists in many shapes and forms. Linked Data can be published using plain RDF files in various syntaxes, such as JSON-LD, Turtle, HTML+RDFa, and more. Next to that, different forms of queryable Web interfaces exist, such as SPARQL endpoints and Triple Pattern Fragments (TPF) interfaces. If we want to query Linked Data from the Web, we need to be able to cope with this heterogeneity.

    Comunica is a quering framework that has been designed to handle different types of Linked Data interfaces in a flexible manner. Its primary goal is executing SPARQL queries over one or more interfaces.

    Comunica is a meta-query engine

    Comunica should not be seen as a query engine. Instead, Comunica is a meta query engine using which query engines can be created. It does this by providing a set of modules that can be wired together in a flexible manner.

    While we provide default configurations of Comunica to easily get started with querying, anyone can configure their own query engine. This fine-tuning of Comunica to suit your own needs, and avoiding the overhead of modules that are not needed.

    For and on the Web

    We strongly believe in the existence of open Web standards, such as those provided by W3C and WhatWG. As such, Comunica implements several specifications such as RDF and SPARQL. Furthermore, Comunica is implemented using Web-based technologies in JavaScript, which enables usage through browsers, the command line, the SPARQL protocol, or any Web or JavaScript application.


    Comunica is an open-source software project that is available under the MIT license, which means that it is allowed to be used in both open and commercial projects. Next to the source code, also our development process is open, which you can read or contribute to on GitHub, or read our high-level roadmap.

    Research and Education

    Comunica is designed as a flexible research platform for research on query execution. As such, our goal is to make it sufficiently easy for researchers to investigate alternative query algorithms and techniques by modifying engines. Next to this, we also aim to educate researchers and developers on how to use Comunica.

    Linked Data Fragments

    One of the motivations behind Comunica is to be a Linked Data Fragments Client. Linked Data Fragments is a theoretical framework to analyse different Linked Data interfaces.

    While software used to exist to query over specific types of Linked Data interfaces, it used to be impossible to query over combinations of different interfaces. Comunica solves this need by being independent of specific types of interfaces, as support for new interfaces can be plugged in.


    A primary goal of Comunica is to acts as a stable querying framework. For this, we spend extra effort in continuous testing at different levels.

    Supporting the JavaScript ecosystem

    Comunica depends on many dependencies to achieve its goals, such as spec-compliant RDF parsers and serializers. We support these libraries, and contribute to them.

    Who works on Comunica?

    First and foremost, Comunica is an open-source framework. The Comunica project has been initiated by IDLab at Ghent University – imec, and is being actively developed and maintained by a variety of contributors. All development happens publicly via GitHub project boards, issues, and pull requests. Anyone is welcome to contribute to this project.

    As of recently, the Comunica Association has been founded as a non-profit organization to make Comunica development more sustainable in the long term.