The current release of Libundo is 0.8.0. The code in this release is The Simplest Thing Which Could Possibly Work. It is very sub-optimal in both execution speed and memory usage. However, the API as it exists in 0.8.0 is likely to be very close to the 1.0.0 API. The code is feature complete. No new major features will be added before 1.0.0. This release is intended to provide application developers with a library to begin using in application development, with the acknowledgement that the performance is not yet what it could be.
For the remainder of the 0.8.x series, the goal is to optimize the performance of libundo, in both speed and memory, to the point that libundo is useful for applications with large amounts of undoable data and a wide variety of memory allocation strategies.
It is likely that Libundo will be modified to use zlib or a similar compression library to compress memory heap snapshots. We will investigate storing memory deltas between sequential snapshots for even tighter memory usage. The memory allocation algorithms used by the memory heap routines will also be improved for speed. A better undo_realloc() will be provided which can potentially reuse existing memory locations. There may be other optimization opportunities as well.
When Libundo is reasonably optimized, we will enter the 0.9.x series. The goal of 0.9.x is simply to clean up any remaining bugs and be sure about the Libundo API before it is frozen in 1.0.0. Example applications will be written to provide easy illustration of the use of libundo. When we are confident about the quality of the code and the API, and some reasonable example applications are available, we will release 1.0.0.
Libundo was designed with a quite simple interface and feature set to promote rapid development. It is hoped that 1.0.0 will be available in the reasonably near future. After the 1.0.0 release, all future versions of Libundo will support the 1.0.0 API for backwards compatibility.
If Libundo is successful enough to warrant continued development, the 1.1.x series will be the first to add new features to libundo.