Book 14 · Programming LanguagesPage 33 of 33

Zig

Updated September 30, 20263 min read

In short

Zig is a low-level systems programming language that aims to be a simpler, safer successor to C, with manual memory management and no hidden control flow.

What is Zig?

Zig is a general-purpose systems programming language created by Andrew Kelley and first announced in 2016. It targets the same kind of work as C, such as operating system components, embedded software, game engines and performance-critical tools, but with modern safety features and clearer rules. Zig is still working toward a stable 1.0 release, so breaking changes between versions are common.

Zig's design follows a few principles: no hidden control flow, no hidden memory allocations, and no preprocessor or macros. Functions that need memory take an allocator as an explicit argument, so you can always see where memory comes from and choose how it is managed. Errors are ordinary values returned in error union types and handled with try and catch, and comptime lets ordinary Zig code run at compile time to generate types and specialize functions, replacing the macros and templates of C and C++.

Zig also works as a C and C++ toolchain: it can import C header files directly, call C functions without extra bindings, and compile C code for many target platforms from one machine, which makes cross-compilation easy. Debug and safe release builds add runtime checks for problems like integer overflow and out-of-bounds access, while the fastest release mode removes them. Using Zig is a bit like driving a manual car with a dashboard that shows every gauge: you are still in full control, but far less is hidden from you.

Zig is often compared with Rust, since both are modern alternatives to C and C++. Rust guarantees memory safety at compile time through its ownership rules and borrow checker, which prevents whole classes of bugs but adds complexity, while Zig keeps manual memory management and relies on explicit allocators, runtime safety checks and testing instead. Zig is also closer to C in spirit: a small language that you can learn completely, with smooth interoperability with existing C code.

Key takeaways

Zig is a systems language positioned as a modern, simpler alternative to C.
Memory is managed manually through explicit allocators passed to functions.
comptime runs Zig code at compile time instead of relying on macros.
It can compile and cross-compile C code and import C headers directly.
Unlike Rust, it has no borrow checker; safety comes from runtime checks and explicit design.

Example

Explicit allocation in Zigzig

const std = @import("std");

pub fn main() !void {
    // Memory comes from an allocator you choose and pass explicitly
    const allocator = std.heap.page_allocator;
    const numbers = try allocator.alloc(u32, 5);
    defer allocator.free(numbers); // freed when main returns

    for (numbers, 0..) |*n, i| {
        n.* = @intCast(i * i);
    }
    std.debug.print("Last square: {d}\n", .{numbers[4]});
}

Readers ask

Is Zig ready for production?

Some companies and open-source projects already ship software written in Zig, but the language has not reached version 1.0 and still changes between releases. Teams using it should expect to update their code when they upgrade the compiler.

What is the difference between Zig and C?

Zig keeps C's manual memory management and low-level control but removes the preprocessor, adds error unions, optional types, compile-time execution and safety checks, and makes allocation explicit. It can also use C libraries directly, so the two can live in one project.

Should I learn Zig or Rust?

Rust offers compile-time memory safety guarantees and a large, stable ecosystem, which suits big teams and security-sensitive code. Zig is smaller and closer to C, which suits developers who want simple, explicit low-level control and easy C interop.

Zig