docs: base images support Fedora/RHEL/Arch/Alpine (drop Debian-only restriction)

docs/template/base-image.mdx

@@ -29,21 +29,33 @@ template = Template(
 
 ## Defining base image
 
-Every template starts with a base image that provides the foundation for your sandbox environment.
+Every template starts with a base image that provides the foundation for your sandbox environment. E2B identifies the image's distribution from its `/etc/os-release`.
+
+**Supported:** Debian/Ubuntu, Fedora and the RHEL family (including Rocky Linux and AlmaLinux), Arch, and Alpine.
+
+**Not supported:**
+
+- Images with no identifiable distribution (no `/etc/os-release`), such as `scratch`, distroless, or pure `nixos/nix`.
+- Minimal images missing required packages, such as RHEL UBI-minimal with restricted repositories.
+
+Unsupported images fail the build with a clear error naming the reason.
 
 <Warning>
-E2B currently supports only Debian-based images. Your base image must be Debian or a Debian derivative (e.g., `debian`, `ubuntu`, `python`, `node`). Alpine, RedHat-based, and other non-Debian distributions are not supported.
+For NixOS, use the official [`e2bdev/nixos`](#nixos-base-image) image instead of a raw NixOS image.
 </Warning>
 
 ### Predefined base images
 
-Use convenience methods for common base images with Ubuntu, Debian, Python, Node.js, or Bun:
+Use convenience methods for common base images with Ubuntu, Debian, Fedora, Alpine, Arch, Python, Node.js, or Bun:
 
 <CodeGroup>
 
 ```typescript JavaScript & TypeScript
 template.fromUbuntuImage("22.04"); // ubuntu:22.04
 template.fromDebianImage("stable-slim"); // debian:stable-slim
+template.fromFedoraImage("44"); // fedora:44
+template.fromAlpineImage("3.24"); // alpine:3.24
+template.fromArchImage("base-devel"); // archlinux:base-devel
 template.fromPythonImage("3.13"); // python:3.13
 template.fromNodeImage("lts"); // node:lts
 template.fromBunImage("1.3"); // oven/bun:1.3
@@ -52,6 +64,9 @@ template.fromBunImage("1.3"); // oven/bun:1.3
 ```python Python
 template.from_ubuntu_image("22.04")  # ubuntu:22.04
 template.from_debian_image("stable-slim")  # debian:stable-slim
+template.from_fedora_image("44")  # fedora:44
+template.from_alpine_image("3.24")  # alpine:3.24
+template.from_arch_image("base-devel")  # archlinux:base-devel
 template.from_python_image("3.13")  # python:3.13
 template.from_node_image("lts")  # node:lts
 template.from_bun_image("1.3")  # oven/bun:1.3
@@ -93,6 +108,22 @@ template.from_base_image()  # e2bdev/base
 
 `base` is also the template used when you call `Sandbox.create()` without specifying one. It is Debian-based and comes with common tooling pre-installed: Python 3, Node.js, Yarn, `git`, `curl`, `build-essential`, and the GitHub CLI (`gh`). For the exact contents, see the public Dockerfile: [`templates/base/e2b.Dockerfile`](https://github.com/e2b-dev/E2B/blob/main/templates/base/e2b.Dockerfile).
 
+### NixOS base image
+
+Arbitrary [NixOS](https://nixos.org/) images (such as `nixos/nix`) aren't supported directly, because they don't expose the `/etc/os-release` metadata E2B needs to identify the distribution. To build NixOS-based sandboxes, use the official `e2bdev/nixos` image, which E2B prepares to work with the sandbox environment:
+
+<CodeGroup>
+
+```typescript JavaScript & TypeScript
+template.fromImage("e2bdev/nixos");
+```
+
+```python Python
+template.from_image("e2bdev/nixos")
+```
+
+</CodeGroup>
+
 ### Default resources
 
 A sandbox gets its CPU and memory from the template it's built on. A sandbox built from `base` starts with **2 vCPU and 512 MiB of RAM**.