Why Zig over C for Systems Programming

Zig is presented as a practical alternative to C for new systems code, not as a rejection of C’s strengths. Both languages are small, lack garbage collection, operate close to the machine, and can use C libraries and the C ABI. The main improvement highlighted is resource cleanup: Zig’s `errdefer` places each cleanup beside its allocation and automatically runs cleanups in reverse order on failure. Its failing allocator also makes it straightforward to test each allocation-failure path and detect leaks. Other advantages include slices that carry their lengths, compile-time code for platform-specific behavior and generic types, and clearer handling of integer overflow.

Zig’s safety checks make accidental overflow visible in debug and safe builds, while explicit operators allow wrapping or saturating arithmetic when intended. Its `zig cc` compiler can also cross-compile C programs, enable undefined-behavior checks, and build C and Zig files together, supporting gradual migration. The choice comes with important limits: Zig does not prevent use-after-free or dangling pointers, and optimized modes can disable many checks. It is also less stable and less widely supported than C; a recent Zig release required changes to many existing files, while old C code remains portable across a vast range of tools and hardware. C remains essential for existing systems and constrained targets, but the author prefers Zig for new code because it retains C’s low-level style while catching more mistakes.