fauxnix

Run Linux-style commands on Windows — natively, deterministically, no VM, no WSL.

fauxnix is a bash→PowerShell translation layer built for AI agents. Your agent keeps writing the bash it already knows (ls -la | grep foo, find . -name '*.ts' | wc -l, kill -9 1234), and fauxnix deterministically translates each command into PowerShell, executes it natively, and hands back output that looks like GNU/Linux: ls -l columns, bash-style error messages, coreutils exit codes, UTF-8/GBK handled automatically.

One-command install for Claude Code · Codex · OpenCode · Kimi Code · Qwen Code, plus any MCP client. 109 translated commands · 1,469 automated tests · 270-case Git Bash differential corpus plus 41 supplementary checks · zero LLM calls at runtime.

This checkout is v2.2.0. See migration and release notes for the Node.js requirement, changed file-operation contracts and verification limits. The npm badge and @latest examples show the published version until publication completes.

Try it now — no install

npx fauxnix-cli@latest "ls -la src | head -3"
npx fauxnix-cli@latest translate "find . -name '*.log' -mtime +7 -delete"

$ fauxnix "ls -la src | head -2"
-rw-r--r-- 1 me me 1204 Aug 16 09:12 ast.ts
-rw-r--r-- 1 me me 8192 Aug 16 09:12 cli.ts

$ fauxnix "cat nope.txt"
cat: nope.txt: No such file or directory        # not a PowerShell stack trace

Connect your agent — one command

npm install -g fauxnix-cli
fauxnix install --claude     # or --codex / --opencode / --kimi / --qwen
fauxnix doctor               # verifies encoding, harness config, and MCP round-trip

Idempotent; prints exactly what changed. Manual configurations below if you prefer to edit config files yourself.

npm package name is fauxnix-cli (the fauxnix name on npm belongs to an unrelated 2015 websocket library); the installed command is fauxnix. Requires Windows with PowerShell 5.1+ (built-in) and Node.js ≥ 22.20.0. Node 18/20 are unsupported in v2. Current Node 22/24 LTS patches are tested. Published v1.0.0 retains its original metadata.

claude mcp add fauxnix -- fauxnix mcp

[mcp_servers.fauxnix]
command = 'C:\Program Files\nodejs\node.exe'
args = ['C:\Users\<you>\AppData\Roaming\npm\node_modules\fauxnix-cli\dist\index.js', 'mcp']

{
  "mcp": {
    "fauxnix": {
      "type": "local",
      "command": ["C:\\Program Files\\nodejs\\node.exe", "C:\\Users\\<you>\\AppData\\Roaming\\npm\\node_modules\\fauxnix-cli\\dist\\index.js", "mcp"]
    }
  }
}