Graphfile is a graph serialization library.

It is currently of limited scope and only meant to support write in
append-only mode where nodes must consist of a binary blob, and links
to other nodes.

The serialized file has the following format:

The file begins with an absolute 64-bit offset, of the "root" node.
The bytes at that offset will contain a Node, of the structure:

Type      Name
gnumber   Size of arbitrary data
binary    Arbitrary data
gnumber   Number of offsets
gnumbers  Unsigned numbers representing relative offsets pointing backwards
