Zig Systems

zig-systems - Systems Programming and Performance

Overview

zig-systems provides low-level systems programming capabilities using Zig - a modern language for systems code with performance of C, memory safety guarantees, and cross-platform compilation.

Role: ERGODIC systems coordinator - bridges high-level skill orchestration (Clojure) with native performance code.

Quick Start

Install Zig

# macOS with Homebrew
brew install zig

# Or download from https://ziglang.org/download/
# Verify installation
zig version

Basic Compilation

# Compile a Zig program
zig build-exe main.zig

# Run compiled binary
./main

# Compile with optimizations
zig build-exe -O ReleaseFast main.zig

# Compile to library (FFI)
zig build-lib main.zig

Language Features

Memory Safety Without GC

const std = @import("std");

pub fn main() void {
    // Stack-allocated, no garbage collection
    var arena = std.heap.ArenaAllocator.init(std.heap.page_allocator);
    defer arena.deinit();

    const allocator = arena.allocator();

    // Explicit allocation
    var list = std.ArrayList(i32).init(allocator);
    defer list.deinit();

    // Type-safe operations
    try list.append(42);
}

Comptime Metaprogramming

fn Matrix(comptime T: type, comptime rows: usize, comptime cols: usize) type {
    return struct {
        data: [rows * cols]T,

        fn get(self: @This(), r: usize, c: usize) T {
            return self.data[r * cols + c];
        }
    };
}

// Compile-time type generation
const IntMatrix = Matrix(i32, 3, 3);

C Interoperability

// Direct C function calls
extern "c" fn malloc(size: usize) ?*anyopaque;
extern "c" fn free(ptr: ?*anyopaque) void;

// Export functions for C/other languages
export fn skill_invoke(input: [*]u8, len: usize) [*]u8 {
    // Process input, return output
}

Project Structure

zig-systems/
├── SKILL.md
├── build.zig          # Build configuration
├── scripts/
│   ├── array_sort.zig
│   ├── compression.zig
│   ├── hash_table.zig
│   └── ffi.zig        # FFI/C interop
├── references/
│   ├── ZIG_SYNTAX.md
│   ├── MEMORY_MODEL.md
│   ├── PERFORMANCE.md
│   └── FFI_GUIDE.md
└── assets/
    └── build_template.zig

Common Tasks

1. Efficient Sorting

const std = @import("std");

pub fn sort_i32(allocator: std.mem.Allocator, items: []i32) !void {
    var list = std.ArrayList(i32).init(allocator);
    defer list.deinit();

    try list.appendSlice(items);
    std.sort.sort(i32, list.items, {}, std.sort.asc(i32));
}

2. Hash Table Operations

const std = @import("std");

pub fn main() !void {
    var gpa = std.heap.GeneralPurposeAllocator(.{}){};
    defer _ = gpa.deinit();
    const allocator = gpa.allocator();

    var map = std.StringHashMap(i32).init(allocator);
    defer map.deinit();

    try map.put("foo", 42);
    if (map.get("foo")) |value| {
        std.debug.print("Found: {}\n", .{value});
    }
}

3. Compression Algorithm

pub fn compress(allocator: std.mem.Allocator, data: []const u8) ![]u8 {
    // Implement compression (e.g., DEFLATE, LZ4)
    var output = std.ArrayList(u8).init(allocator);
    defer output.deinit();

    // Compression logic here

    return output.toOwnedSlice();
}

4. Performance Benchmarking

const std = @import("std");

pub fn benchmark(comptime name: []const u8, func: fn() void) void {
    var timer = try std.time.Timer.start();
    defer {
        const elapsed = timer.read();
        std.debug.print("{s}: {d}ns\n", .{name, elapsed});
    }

    func();
}

Performance Characteristics

Compilation Speed

• Incremental: ~100ms for small modules
• Full rebuild: ~500ms - 2s
• Release build: ~1-5s with optimizations

Runtime Performance

• Memory usage: Minimal (no GC overhead)
• Binary size: 1-10MB depending on features
• Startup time: <1ms for most programs
• CPU efficiency: Near-C performance

Comparison

Building Zig Projects

Simple build.zig

const std = @import("std");
const Builder = std.build.Builder;

pub fn build(b: *Builder) void {
    const target = b.standardTargetOptions(.{});
    const optimize = b.standardOptimizeOption(.{});

    const exe = b.addExecutable(.{
        .name = "my_skill",
        .root_source_file = .{ .path = "main.zig" },
        .target = target,
        .optimize = optimize,
    });

    b.installArtifact(exe);

    const run_cmd = b.addRunArtifact(exe);
    const run_step = b.step("run", "Run the app");
    run_step.dependOn(&run_cmd.step);
}

Build Commands

# Build debug binary
zig build

# Build with optimizations
zig build -Doptimize=ReleaseFast

# Install to prefix
zig build --prefix /usr/local install

# Run tests
zig build test

Integration with Other Skills

Calling from Clojure

(defn call-zig-sort [data]
  "Invoke Zig sort via FFI."
  (shell/sh "zig-systems" "sort" (write-json data)))

Calling from Go

import "C"

//export SkillInvoke
func SkillInvoke(data *C.char) *C.char {
    // Call Zig compiled library
    result := C.zig_compress(data)
    return result
}

Calling from Hy

(import subprocess)
(setv result (subprocess.run ["zig-systems" "compress" "input.dat"]
                            :capture-output True))

When to Use

• Performance-critical code: Sorting, compression, hashing
• System-level operations: File I/O, memory management, POSIX APIs
• Cross-platform binaries: Compile once, run anywhere (Linux, macOS, Windows)
• FFI requirements: Need to call from other languages
• Memory-constrained systems: Embedded, IoT, serverless
• Real-time systems: Predictable performance, no GC pauses

When NOT to Use

• High-level business logic (use Clojure)
• Quick prototyping (Hy/Python faster iteration)
• Dynamic typing requirements (Zig is statically typed)
• GC convenience preferred over control

GF(3) Consideration

While zig-systems is a SINGLE language skill (not a triadic component itself), it coordinates with:

Validator (-1) + Coordinator (0) + Generator (+1) ≡ 0 (mod 3)
 [joker]        [zig-systems]    [hy-regime]
       OR
 [joker]      [jo-clojure]       [hy-regime]

Zig provides low-level system optimization that the triadic coordinator (jo-clojure or zig-systems) may invoke.

Debugging

Runtime Assertions

const std = @import("std");

pub fn divide(a: i32, b: i32) i32 {
    std.debug.assert(b != 0);  // Panics if false
    return a / b;
}

Error Handling

const FileOpenError = error {
    FileNotFound,
    PermissionDenied,
};

pub fn open_file(path: []const u8) FileOpenError!*File {
    if (!file_exists(path)) {
        return FileOpenError.FileNotFound;
    }
    // ...
}

Standard Library Utilities

const std = @import("std");

pub fn main() void {
    std.debug.print("Debug output: {any}\n", .{data});
    std.debug.assert(condition);
    var timer = std.time.Timer.start();
}

Performance Optimization Tips

1. Use ReleaseFast or ReleaseSmall optimization levels
2. Minimize allocations: Preallocate where possible
3. Use inline functions: inline keyword for hot paths
4. Leverage comptime: Compute at compile time, not runtime
5. Profile with perf: perf record ./binary then perf report
6. Consider SIMD: @Vector type for parallel operations

References

• Zig Language Documentation
• Zig Standard Library
• Zig by Example
• Memory Model Guide
• FFI Integration
• Performance Tuning

Troubleshooting

"zig: command not found"

• Install Zig: brew install zig
• Verify: zig version
• Update PATH if needed

Build errors with C libraries

• Use zig build-exe main.zig -lc to link libc
• Declare C imports explicitly: extern "c" fn malloc(...)

Memory leaks in debug mode

• Use GeneralPurposeAllocator for testing
• Enable leak detection: std.heap.GeneralPurposeAllocator(.{.safety = true})

Binary too large

• Use ReleaseSmall optimization: -O ReleaseSmall
• Strip debug symbols: strip ./binary