---
product: Chilkat
product_version: 11.7.0
language: zig
language_label: Zig
document: language guide
---
> Chilkat 11.7.0 · language=zig · this file: `https://www.chilkatsoft.com/ai-docs/v/11.7.0/zig/guide.md`
> Class pages: `https://www.chilkatsoft.com/ai-docs/v/11.7.0/zig/classes/<Class>.md`

# Chilkat for Zig — language guide — v11.7.0

## 1. Which Chilkat binding this is

This is the **Chilkat package for Zig** (`@import("chilkat")`, Zig 0.16.x): one-pointer structs `chilkat.Http`, `chilkat.Zip`, … created with `try chilkat.Http.init()` and released with `deinit()`; camelCase methods that return **error unions**; string results are allocated with the caller's `allocator`. A C API (`chilkat.c.CkHttp`) is reachable from the same package for anything the Zig API does not cover. The prebuilt native library for the target is downloaded at build time.

## 2. Install and requirements

```
zig fetch --save https://chilkatdownload.com/11.7.0/chilkat-zig-11.7.0.tar.gz
```

then in `build.zig`: `const chilkat = b.dependency("chilkat", .{ .target = target, .optimize = optimize }); exe.root_module.addImport("chilkat", chilkat.module("chilkat"));`. Details: [https://www.chilkatsoft.com/zig.asp](https://www.chilkatsoft.com/zig.asp).

## 3. Unlocking, object creation, lifetime and errors

Generated from the reference documentation for this binding:

**Object Creation**

```zig
// Add the package once:
//     zig fetch --save https://chilkatdownload.com/11.7.0/chilkat-zig-11.7.0.tar.gz
// and in build.zig:
//     const chilkat = b.dependency("chilkat", .{ .target = target, .optimize = optimize });
//     exe.root_module.addImport("chilkat", chilkat.module("chilkat"));
const chilkat = @import("chilkat");

// Once per process, before any other Chilkat call:
try chilkat.unlockBundle("Anything for 30-day trial");

const global = try chilkat.Global.init();
defer global.deinit();
```

`pub fn init() Allocator.Error!Global`

Creates the underlying native Chilkat object. `Global` is a one-pointer struct passed by value; copying it copies the handle (two names for one object). Returns `error.OutOfMemory` if the library could not allocate the object. Use an object from one thread at a time; it may be handed from one thread to another.

`pub fn deinit(self: Global) void`

Releases the native object. Call it exactly once per object (usually with `defer`); the handle is invalid afterwards. Objects returned by methods are owned by the caller too and are released the same way.

`pub fn fromHandle(h: *chilkat.c.CkGlobal.HCkGlobal) Global`

Wraps a handle obtained from the C API (`chilkat.c.CkGlobal`), taking ownership of it. The struct's `handle` field goes the other way, for anything the Zig API does not cover.

**Errors and memory**

Methods that can fail return an error union: a method whose only outcome is success or failure returns `Error!void`; a method producing a string returns `(Error || Allocator.Error)![:0]u8`; a method producing an object returns `Error!T`. `chilkat.Error` is `error{ChilkatFailed}`; the reason for a failure is in `getLastErrorText`, and the object remains usable. Properties never fail, and methods that answer a question (`hasMember`, `isUnlocked`, ...) return a plain `bool`.

String arguments are `[:0]const u8` (UTF-8; string literals can be passed as is). String results are copies allocated with the `allocator` argument and owned by the caller, so they stay valid across later calls on the same object.

```zig
const text = global.someMethod(allocator, ...) catch |err| {
    const why = try global.getLastErrorText(allocator);
    defer allocator.free(why);
    std.debug.print("{s}\n", .{why});
    return err;
};
defer allocator.free(text);
```

## 4. Error model

Methods that can fail return an **error union**: `Error!void` for success/failure methods, `(Error || Allocator.Error)![:0]u8` for string results, `Error!T` for objects. `chilkat.Error` is `error{ChilkatFailed}`; the reason is in `try obj.getLastErrorText(allocator)` (free it afterwards) and the object remains usable. Properties never fail; question methods (`hasMember`, `isUnlocked`, …) return a plain `bool`. The note under each method on the class page restates this per method.

Literals in Zig: true is `true`, false is `false`, null/none is `error.ChilkatFailed`.

## 5. Strings, bytes and encodings

- String arguments are `[:0]const u8` (UTF-8; literals can be passed as is). String results are copies allocated with the `allocator` argument, owned by the caller (`defer allocator.free(s)`), so they stay valid across later calls.
- Binary data is `[]const u8` in and an allocated `[]u8` out; larger or reusable data goes through `chilkat.BinData` (`…Bd` methods) and text through `chilkat.StringBuilder` (`…Sb` methods).
- Methods with `2`/`3` suffixes or `quick…` prefixes are distinct members, not overloads.

## 6. Object lifetime and threading

Call `deinit()` exactly once per object (usually `defer`), including objects returned by methods; copying the struct copies the handle (two names for one object).

A Chilkat object may be used from any thread, but **one object must not be used by two threads at the same time**: create one object per thread or protect it with a lock. Objects are independent — there is no shared global state other than the unlock flag and the few `Global` settings.

## 7. Progress callbacks and async

Progress events are supported through the class's event callbacks (see the "Events and callbacks" section of a class page). Every call is synchronous.

## 8. Common mistakes an AI makes with this binding

1. Checking for `null`/`false` instead of handling the error union (`try` / `catch`).
2. Forgetting `defer allocator.free(...)` on string results, or `deinit()` on objects.
3. Using PascalCase member names from other bindings; Zig members are camelCase (`quickGetStr`, `getLastErrorText`).
4. Omitting `Global.UnlockBundle` (the program runs in trial mode and stops working after 30 days).
5. Inventing members by analogy with other libraries. If a member is not on the class page, it does not exist — look it up rather than guessing.
6. Using deprecated members that older examples still show. The class page lists each one with its replacement; `deprecated.md` lists them all.
7. Ignoring the failure path. Every Chilkat method reports failure (see each method's note); `LastErrorText` says why, and printing it is the first debugging step.
8. Using one Chilkat object from two threads at the same time. Create one object per thread, or protect it with a lock.

## 9. Instructions block for coding agents

Paste into `CLAUDE.md`, `.cursor/rules`, or Copilot instructions:

```
This project uses Chilkat 11.7.0 from Zig (the chilkat Zig package; structs chilkat.Http etc., camelCase methods returning error unions).
- Reference: https://www.chilkatsoft.com/ai-docs/v/11.7.0/zig/ — read guide.md once, then classes/<Class>.md for each class used.
- Call try chilkat.unlockBundle(...) once at startup; init()/deinit() every object.
- Failures are error.ChilkatFailed: catch the error and print try obj.getLastErrorText(allocator); free string results.
- Never use a member that is not on the class page; never use members listed as deprecated.
```

## 10. Classes

[Class index for Zig](https://www.chilkatsoft.com/ai-docs/v/11.7.0/zig/index.md)