# zig-dotenv
A powerful Zig library for loading, parsing, and managing environment variables from `.env` files.
[](README.md)
[](LICENSE)
[](https://github.com/xcaeser/zig-dotenv/releases)
## Docs:
[dotenv reference docs](https://xcaeser.github.io/zig-dotenv)
## โ
Features
- Load environment variables from `.env` files
- Type-safe access using enums
- Read from and copy the current process environment map
- Modify the **current process environment** with `setProcessEnv`
- Supports comments, quoted values, and whitespace trimming
- Supports `$KEY` and `${KEY}` interpolation from the process environment map
- Missing keys return an empty string
- Clean, testable API
## ๐ Usage
```zig
const std = @import("std");
const dotenv = @import("dotenv");
pub const EnvKeys = enum {
OPENAI_API_KEY,
AWS_ACCESS_KEY_ID,
COGNITO_CLIENT_SECRET,
S3_BUCKET,
};
pub fn main(process_init: std.process.Init) !void {
var env = dotenv.init(process_init, EnvKeys);
defer env.deinit();
try env.load(.{
.filename = ".env.local",
.include_current_process_envs = true,
});
const openai = env.key(.OPENAI_API_KEY);
std.debug.print("OPENAI_API_KEY={s}\n", .{openai});
const aws_key = env.get("AWS_ACCESS_KEY_ID");
std.debug.print("AWS_ACCESS_KEY_ID={s}\n", .{aws_key});
}
```
## ๐ Example `.env` File
```dotenv
OPENAI_API_KEY=sk-your-api-key-here
AWS_ACCESS_KEY_ID=AKIAIOSFODNN7EXAMPLE
S3_BUCKET="my-bucket"
COGNITO_CLIENT_SECRET='abcdef123456'
HOME_DIR=$HOME
USER_NAME=${USER}
```
## ๐ฆ Installation
### using `zig fetch`
```bash
zig fetch --save=dotenv https://github.com/xcaeser/zig-dotenv/archive/v0.9.0.tar.gz
```
### Add to `build.zig`
```zig
const dotenv_dep = b.dependency("dotenv", .{ .target = target, .optimize = optimize });
exe.root_module.addImport("dotenv", dotenv_dep.module("dotenv"));
// Optional: add for unit tests
exe_unit_tests.root_module.addImport("dotenv", dotenv_dep.module("dotenv"));
```
## ๐ API Summary
### Initialization
`zig-dotenv` uses Zig `0.16.0`'s `std.process.Init` API. Accept it in `main`, then create an env manager with your enum type:
```zig
pub fn main(process_init: std.process.Init) !void {
var env = dotenv.init(process_init, EnvKeys);
defer env.deinit();
}
```
### Env API
| Method | Description |
| ------------------------------------------------------- | ------------------------------------------------ |
| `dotenv.init(process_init, EnvKey)` | Initializes a new Env manager |
| `deinit()` | Frees all allocated memory |
| `load(.{ .filename, .include_current_process_envs })` | Loads variables from a `.env` file |
| `loadCurrentProcessEnvs()` | Copies process variables into the internal map |
| `parse(content)` | Parses raw `.env`-formatted text |
| `get("KEY")` | Gets a value by string key, or `""` if missing |
| `key(.ENUM_KEY)` | Gets a value by enum key, or `""` if missing |
| `setProcessEnv("KEY", "VALUE")` | Sets a process environment variable |
| `setProcessEnv("KEY", null)` | Unsets a process environment variable |
### Load Options
| Option | Default | Description |
| ------------------------------ | ------- | ------------------------------------------------ |
| `filename` | `.env` | File to load |
| `include_current_process_envs` | `false` | Copies `process_init.environ_map` into the map |
| `export_to_process_env` | `false` | Reserved; not currently implemented |
## ๐งช Testing
Run:
```bash
zig build test
```
Includes tests for parsing, file I/O, interpolation, process environment loading, and lookup behavior.
## ๐ค Contributing
Issues and PRs welcome! Star the repo if it helped you.
## ๐ License
MIT โ see [LICENSE](LICENSE).