Do you develop on GitHub? You can keep using GitHub but automatically sync your GitHub releases to SourceForge quickly and easily with this tool so your projects have a backup location, and get your project in front of SourceForge's nearly 20 million monthly users. It takes less than a minute. Get new users downloading your project releases today!
The technology in question reminds me of VTD-XML (Virtual Token Descriptor). Make an index that points into the document, "starting offset and length" as described here: VTD in 30 seconds. i4i's "map" is VTD's "index" + "location cache". But no one's talking about it.