Linux servers

Apostate runs on a Linux server with no GPU and no display. The persona’s WebGL values are served whatever the server renders with. The WebGPU adapter is served only in a headed launch as a regular user, as Headless or headed shows. The default persona on Linux is Windows, so a server needs the Windows fonts as well as the browser.

Set up the server

Install the system packages

The lib packages are the libraries the browser links against. fontconfig and git are for the fonts, xvfb is for headed launches, zstd lets Python below 3.14 unpack the browser archive, and python3-venv is for the next step.

Debian 13, Ubuntu 24.04
Debian 12, Ubuntu 22.04

sudo apt-get update
sudo apt-get install --no-install-recommends \
  libasound2t64 libatk-bridge2.0-0t64 libatk1.0-0t64 libatspi2.0-0t64 \
  libcairo2 libcups2t64 libdbus-1-3 libexpat1 libgbm1 libglib2.0-0t64 \
  libnspr4 libnss3 libpango-1.0-0 libx11-6 libxcb1 libxcomposite1 \
  libxdamage1 libxext6 libxfixes3 libxkbcommon0 libxrandr2 \
  ca-certificates fontconfig git xvfb zstd python3-venv

sudo apt-get update
sudo apt-get install --no-install-recommends \
  libasound2 libatk-bridge2.0-0 libatk1.0-0 libatspi2.0-0 \
  libcairo2 libcups2 libdbus-1-3 libexpat1 libgbm1 libglib2.0-0 \
  libnspr4 libnss3 libpango-1.0-0 libx11-6 libxcb1 libxcomposite1 \
  libxdamage1 libxext6 libxfixes3 libxkbcommon0 libxrandr2 \
  ca-certificates fontconfig git xvfb zstd python3-venv

The libraries are what ldd reports missing for the 0.4.3 browser on a minimal image. With them, the browser started headless on Debian 12, Debian 13, Ubuntu 22.04 and Ubuntu 24.04 (arm64 containers, 2026-09-27).

Install the package and the browser

python3 -m venv ~/apostate-venv
. ~/apostate-venv/bin/activate
pip install apostate
apostate install

npm install @heretic-tech/apostate
npx apostate install

On Debian 13 and Ubuntu 24.04, pip install outside a virtual environment fails with externally-managed-environment. The Node package needs Node 22 or later. Installation covers the cache and offline installs.

Install the Windows fonts

apostate fonts install windows

npx apostate fonts install windows

A Windows persona shows only the Windows fonts installed on the host. The command installs them for the current user, so run it as the user that runs the browser. Fonts explains what it installs. To present the server’s own OS instead, pass fingerprint_platform="linux" (Node: fingerprintPlatform: "linux"), which needs no fonts installed.

Headless launches

headless=True (Node: headless: true) is the default and needs no display. The package passes --headless=new. The browser leaves HeadlessChrome out of the User-Agent, where stock Chromium writes it in headless mode.

Headed launches

With headless=False on a host where WAYLAND_DISPLAY is unset and DISPLAY names no X server that answers, the package starts Xvfb, gives its display to the browser, and stops it when the browser closes. It takes the first free display from :99 up and sets DISPLAY only in the browser’s environment.

from apostate import launch

browser = launch(
    fingerprint=42,
    fingerprint_platform="windows",
    locale="en-US",
    timezone="America/New_York",
    headless=False,
)
page = browser.new_page()
page.goto("https://example.com")
print(page.evaluate("[navigator.platform, screen.width, screen.height, outerHeight - innerHeight]"))
browser.close()

import { launch } from "@heretic-tech/apostate";

const browser = await launch({
  fingerprint: 42,
  fingerprintPlatform: "windows",
  locale: "en-US",
  timezone: "America/New_York",
  headless: false,
});
const page = await browser.newPage();
await page.goto("https://example.com");
console.log(await page.evaluate(() => [navigator.platform, screen.width, screen.height, outerHeight - innerHeight]));
await browser.close();

['Win32', 1920, 1080, 143]

The 143 includes a 56-pixel bar on the first tab, which Headless or headed explains. The display is the size of the screen you set with --fingerprint-screen-width and --fingerprint-screen-height, or that a profile names, and 3840x2160 otherwise. Each headed launch has its own Xvfb, which used 37 MiB at 3840x2160 (PSS, Debian 13 container). Without Xvfb installed, a headed launch fails with:

Xvfb is not installed; install it (apt install xvfb) or pass headless=True

To run the browser binary headed without the packages, start it under xvfb-run, which needs the xauth package, and pass --no-first-run for a new user data directory. Raw binary has the command.

Headless or headed

Two values a page can read differ between the modes. Measured on 2026-09-27 with 0.4.3 in a Debian 13 container (linux-arm64, no GPU), seed 42, Windows persona, run as a regular user:

Value	Headless	Headed under Xvfb
`navigator.gpu.requestAdapter()`	`null`	the persona’s adapter (`intel`, `gen-12lp`)
`outerHeight - innerHeight`	87	143

The same launches in an amd64 container gave the same WebGPU result. Known gaps tracks it. On a Mac, headless also read 87 for outerHeight - innerHeight and served the adapter. The headed 143 is the same 87 plus Chromium’s bar for --no-sandbox, 56 pixels high, which the headed launch showed on its first tab. The packages pass that flag as root and in a container, where the sandbox cannot start. Google Chrome never shows the bar. A bar on the first tab has the workaround, and Browser chrome height compares 87 with real Windows. Run headed on a server when the pages you visit use WebGPU.

Run as a regular user

Under root, navigator.gpu.requestAdapter() returned null in headed launches too (same container and date). Run the browser as a regular user. Run apostate install and apostate fonts install windows as that user too, because both install into the user’s home directory. If you run as root anyway:

The packages work as they are. Their driver, Patchright or Playwright, passes --no-sandbox on every launch.
The browser binary run on its own exits with Running as root without --no-sandbox is not supported. See https://crbug.com/638180. Add --no-sandbox to its switches.

Server size

A persona never claims more cores or memory than the host has. The browser counts the logical CPUs its process may run on and the physical memory the kernel reports. --fingerprint-explain prints both:

apostate run -- --fingerprint=42 --fingerprint-platform=windows --fingerprint-explain | grep "^  host"

  host platform       linux
  host cores          2
  host memory         16818978816 bytes
  host backend        swiftshader (no DRM render node on this host, not probed)

On this 2-CPU host, seed 42 presents 2 cores. On a 14-core host the same seed presents 12. Hosts shows how many seeds keep their own cores and memory on each server size.

x86 or arm64

Use an x86 server for Windows and Linux personas. On an arm64 server they report arm in Sec-CH-UA-Arch next to a desktop Intel or NVIDIA GPU. No real Windows machine has that pair, and iphey.com flags it. Hosts explains why.

Check the server

Verify has a script that prints what a page, a worker and the request headers show. Run it on the server, with --headed for a headed launch.

Get started

Concepts

Configure

Run in production

Help

Set up the server

Headless launches

Headed launches

Headless or headed

Run as a regular user

Server size

x86 or arm64

Check the server

​Set up the server

​Headless launches

​Headed launches

​Headless or headed

​Run as a regular user

​Server size

​x86 or arm64

​Check the server

Set up the server

Headless launches

Headed launches

Headless or headed

Run as a regular user

Server size

x86 or arm64

Check the server