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XARs: An efficient system for self-contained executables

XARs: An efficient system for self-contained executables

7/13/2018 · Chip Turner, Nick Terrell, Cooper Lees

What this post added

This post introduces XARs (Executable Archives), a new system for distributing self-contained executables. XARs encapsulate code and data dependencies into single, highly compressed files, offering significant improvements in distribution speed, robustness, and efficiency compared to previous methods like PARs and PEX files. They leverage squashfs and FUSE for on-demand mounting and execution, minimizing overhead and enabling hermetic binaries that run consistently across diverse infrastructure. The post details the technical implementation, performance benefits, and provides usage examples for various platforms, while also highlighting its open-source release.

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