A binary download is available for v1.0
This repository is a fork of Oracles Nashorn engine (specifies EcmaScript 5.1 / comes with Java 8 / JDK8, accessible via JSR223). Unlike the original engine, this version is able to run on Java 7 / JDK7. The original backport is done by Ramonza. It is released under the GPLv2.
Build using Gradlew:
$ sh gradlew # *nix
$ gradlew.bat # Windows
A Maven repository is coming...