Lbzip2 is a parallel, SMP-based, bzip2-compatible compression utility, with a commandline resembling that of the original bzip2. It is usable both on its own and as a filter passed to GNU tar with the "--use-compress-program" option. It uses Gnulib, and its building and testing process is managed by the GNU build system. Starting with release 2.0, lbzip2 is independent of libbz2 and features yambi, an independent BWT compression stack with improved speed and robustness.
Lzip is a lossless data compressor based on the LZMA algorithm, with very safe integrity checking and a user interface similar to the one of gzip or bzip2. Lzip decompresses almost as quickly as gzip and compresses better than bzip2, which makes it well suited for software distribution and data archiving. If you ever need to recover data from a damaged lzip file, try the lziprecover program.
open-vcdiff contains an encoder and decoder for the format described in RFC 3284: "The VCDIFF Generic Differencing and Compression Data Format." Given a source file and target file, the encoder produces a compact delta file expressing the differences between the two. The decoder reconstructs the target file from the source and delta files. The package includes libraries, headers, and a command-line executable. The chief reason for developers to use open-vcdiff instead of the existing Xdelta package is that open-vcdiff has been released under the Apache license rather than GPL.
EXIficient is an implementation of the W3C Efficient XML Interchange (EXI) format specification written in the Java programming language. The EXI format is a very compact representation for the Extensible Markup Language (XML) Information Set that is intended to simultaneously optimize performance and the utilization of computational resources.
Easylzma is a C library and command line tools for LZMA compression and decompression. It uses Igor Pavlov's reference implementation and SDK. It is meant to be a tiny wrapper and portable build system around a subset of Igor Pavlov's LZMA compression and decompression implementation. The API is small and intended to be straightforward. The project aims to support multiple different prominent LZMA file formats and is focused on producing something that is easy to build and use everywhere.