File format

A .nifdi.svg file is an augmented SVG: one file contains both a rendered vector image and the structured diagram data nifdi needs for editing.

Why SVG

The visible part of the file is standard SVG. You can view it in a browser, embed it in a web page or README, and use it in software that accepts SVG without first exporting a separate image.

The .nifdi.svg suffix makes the file’s second purpose explicit and helps tools distinguish an editable nifdi diagram from an ordinary SVG asset.

What nifdi adds

Inside the SVG’s metadata element, nifdi stores a namespaced description of the diagram: its blocks, paths, hierarchy, placements, styles, and title. nifdi reads that model when it reopens the file and regenerates the rendered SVG from it when the diagram is saved.

The rendered image and editable model therefore travel together. There is no separate source file to keep in sync, and the file can be stored, shared, or committed to version control like any other project file.

Handle the file as an editable document

Software that only understands SVG will ignore nifdi’s metadata and display the picture normally. However, an SVG optimiser or editor may remove that metadata, or may change only the rendered picture without updating the nifdi model. Those changes can make the file non-editable or disappear the next time nifdi saves it.

Keep the metadata intact and make lasting diagram changes in nifdi or through its MCP tools. If you only need a final image for software that rewrites SVG, work on a copy so the .nifdi.svg original remains editable.