Nix flake packaging @playwright/cli, @playwright/mcp, Node.js playwright, .NET Microsoft.Playwright, and PyPI playwright, each bundled with the exact browser revisions its playwright-core requires. No runtime downloads, no PLAYWRIGHT_BROWSERS_PATH wiring needed.

Supported systems: x86_64-linux, aarch64-linux, aarch64-darwin.

@playwright/cli, @playwright/mcp, Node.js playwright, .NET Microsoft.Playwright, and PyPI playwright release independently and regularly pin different playwright-core versions at the same moment. nixpkgs's playwright-driver.browsers almost never matches any of them. This flake builds a separate browser set per consumer and bakes the right one into each wrapper.

Refer to pin.json for the current version of each package.

Add the input:

inputs.playwright.url = "github:halfwhey/nix-playwright-nightly";

Version segments use underscores because the Nix CLI parses dots as attribute path separators (0.1.6 becomes 0_1_6).

playwright.packages.${system}.playwright-cli        # latest
playwright.packages.${system}.playwright-cli-0_1_6  # pinned

$ playwright-cli --version
$ playwright-cli open --browser=chromium https://example.com
$ playwright-cli codegen https://example.com

playwright.packages.${system}.playwright-mcp         # latest
playwright.packages.${system}.playwright-mcp-0_0_70  # pinned

Use as an MCP server:

{
  "mcpServers": {
    "playwright": {
      "command": "playwright-mcp"
    }
  }
}

The package attribute is playwright-node, and the wrapped executable is also named playwright-node to avoid colliding with PyPI playwright's playwright executable. When used as a shell package or build input, it also adds its module tree to NODE_PATH so plain node can require("playwright").

playwright.packages.${system}.playwright-node         # latest
playwright.packages.${system}.playwright-node-1_59_1  # pinned

$ playwright-node --version
$ node -e "const { chromium } = require('playwright'); console.log(typeof chromium)"

playwright.packages.${system}.playwright-python          # latest
playwright.packages.${system}.playwright-python-1_58_0   # pinned

$ playwright --version
$ python -c "from playwright.sync_api import sync_playwright; print('ok')"

playwright.packages.${system}.playwright-dotnet         # latest
playwright.packages.${system}.playwright-dotnet-1_59_0  # pinned

$ playwright-dotnet --version
$ playwright-dotnet codegen https://example.com

For derivations that embed playwright and manage PLAYWRIGHT_BROWSERS_PATH themselves:

playwright.packages.${system}.playwright-cli-browsers              # latest
playwright.packages.${system}.playwright-mcp-0_0_70-browsers      # pinned
playwright.packages.${system}.playwright-node-1_59_1-browsers     # pinned
playwright.packages.${system}.playwright-dotnet-1_59_0-browsers   # pinned
playwright.packages.${system}.playwright-python-1_58_0-browsers   # pinned

{
  inputs = {
    nixpkgs.url = "github:NixOS/nixpkgs/nixos-unstable";
    playwright.url = "github:halfwhey/nix-playwright-nightly";
  };

  outputs = { self, nixpkgs, playwright }:
    let system = "x86_64-linux"; in {
      devShells.${system}.default =
        nixpkgs.legacyPackages.${system}.mkShell {
          packages = [
            playwright.packages.${system}.playwright-cli
            playwright.packages.${system}.playwright-mcp-0_0_70
            playwright.packages.${system}.playwright-node
            playwright.packages.${system}.playwright-dotnet
            playwright.packages.${system}.playwright-python-1_58_0
          ];
        };
    };
}

$ nix develop
$ playwright-cli open --browser=chromium https://example.com
$ playwright-mcp --version
$ playwright-node --version
$ playwright-dotnet --version
$ playwright --version

# one-off run
nix run github:halfwhey/nix-playwright-nightly#playwright-cli-0_1_5 -- open https://example.com

# list all available versions
nix flake show github:halfwhey/nix-playwright-nightly

# NixOS system package
environment.systemPackages = [ inputs.playwright.packages.${pkgs.system}.playwright-cli ];

Browser closures are published to https://halfwhey.cachix.org. Set it up once:

cachix use halfwhey

Or pass it explicitly for a one-off build:

nix build \
  --option extra-substituters https://halfwhey.cachix.org \
  --option extra-trusted-public-keys \
    'halfwhey.cachix.org-1:6PtY2HXdJg8gVVe/uyWGqeWXg1cjfQEIi514Gsk4EeI=' \
  github:halfwhey/nix-playwright-nightly#playwright-cli

Current cache coverage:

• x86_64-linux via ubuntu-latest
• aarch64-linux via ubuntu-24.04-arm
• aarch64-darwin via macos-26

Darwin note: Playwright supports the mac26-arm64 host platform, but in the upstream download registry the current pinned revisions still map that host to the webkit-mac-15-arm64 artifact. This flake mirrors that behavior, so the aarch64-darwin cache uses the macos-26 runner while still fetching the matching webkit-mac-15-arm64 bundle.

./scripts/update-cli.sh          # bump cli to latest on npm
./scripts/update-cli.sh 0.1.4    # bump cli to a specific version
./scripts/update-mcp.sh          # bump mcp to latest on npm
./scripts/update-node.sh         # bump node playwright to latest on npm
./scripts/update-dotnet.sh       # bump Microsoft.Playwright to latest on NuGet
./scripts/update-python.sh       # bump python to latest on PyPI

Each script resolves the matching playwright-core version, prefetches all hashes, writes the pin file, and commits. Re-running with an already-pinned version is a no-op.

CI runs the same update flow once a day. See .github/workflows/sync.yml.

• Per-browser fetchers under lib/browsers/ are adapted from pietdevries94/playwright-web-flake.
• Thank you Cachix for hosting my binary cache for free.