Linked Data API is a configurable API layer intended to support the creation of simple RESTful APIs to be deployed as a proxy in front of a SPARQL endpoint to support:

• Generation of documents (information resources) for the publishing of Linked Data;
• Provision of sophisticated querying and data extraction features, without the need for end-users to write SPARQL queries;
• Delivery of multiple output formats from these APIs, including a simple serialisation of RDF in JSON syntax.

The Linked Data API provides a configurable way to access RDF data using simple RESTful URLs that are translated into queries to a SPARQL endpoint.
The API developer writes an API spec (in RDF) which specifies how to translate URLs into queries.

Read the Linked Data API specification.

ELDA is an open source implementation of the Linked Data API created by Epimorphics Ltd.

Elda is written in Java using Jena RDF toolkit and some of the Jena developers are also actively working on ELDA.