Project 4: Build a zig build Script for a C Project

A build.zig file that compiles an existing C project (like a small library or command-line tool) and cross-compiles it for another architecture (e.g., ARM).

Quick Reference

Attribute Value
Primary Language Zig
Alternative Languages (Build systems like Make, CMake)
Difficulty Level 2: Intermediate
Time Estimate Weekend
Knowledge Area Build Systems / C Interoperability
Tooling Zig as a C compiler/linker
Prerequisites Project 3, basic knowledge of how C code is compiled.

What You Will Build

A build.zig file that compiles an existing C project (like a small library or command-line tool) and cross-compiles it for another architecture (e.g., ARM).

Why It Matters

This project builds core skills that appear repeatedly in real-world systems and tooling.

Core Challenges

  • Setting up the build script → maps to understanding the build function and Builder API
  • Adding C source files → maps to using addExecutable or addStaticLibrary with .c files
  • Linking against C standard library → maps to using linkSystemLibrary("c")
  • Cross-compiling → maps to setting a different target with .setTarget()

Key Concepts

Real-World Outcome

# On your x86-64 Mac:
$ zig build -Dtarget=aarch64-linux-gnu

# In zig-cache/bin:
$ file my-c-app
my-c-app: ELF 64-bit LSB executable, ARM aarch64, version 1 (SYSV), dynamically linked...

Implementation Guide

  1. Reproduce the simplest happy-path scenario.
  2. Build the smallest working version of the core feature.
  3. Add input validation and error handling.
  4. Add instrumentation/logging to confirm behavior.
  5. Refactor into clean modules with tests.

Milestones

  • Milestone 1: Minimal working program that runs end-to-end.
  • Milestone 2: Correct outputs for typical inputs.
  • Milestone 3: Robust handling of edge cases.
  • Milestone 4: Clean structure and documented usage.

Validation Checklist

  • Output matches the real-world outcome example
  • Handles invalid inputs safely
  • Provides clear errors and exit codes
  • Repeatable results across runs

References