lib0xc is a new library providing safer C standard library-adjacent APIs for systems programmers who want better memory and type safety without abandoning C. While C cannot be made completely type-safe at the language level, the project argues that its prevailing uses can be made much safer through better-designed APIs and compile-time checks.

The library's core goal is enabling projects to compile with maximum warning flags including -Wall -Wextra -Werror without triggering build failures. Many high-value warnings get disabled in practice because they conflict with strict error handling or require clumsy workarounds. lib0xc addresses this by designing APIs that work cleanly with strict compilation while embracing clang's bounds safety extensions.

The project includes standard library extensions like alloc.h for typed allocation, int.h for safe integer conversions that trap on overflow, cursor.h for allocation-free I/O, and string.h for static string variants. Systems programming utilities cover bounded buffers, logging, hash tables, and unit testing. Most APIs are macros leveraging the C preprocessor to expose compile-time size information, making it easier to use correctly than incorrectly.

Building requires C11 with GNU extensions (-std=gnu11), clang or GCC, and GNUMake 3.81+. Supported platforms include macOS and Linux on arm64 and x86_64. The project welcomes contributions and provides guidance for porting to new runtime environments.