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Wippy

Network Overlays

Network Overlays

Section titled “Network Overlays”

Route outbound HTTP calls and spawned processes through SOCKS5, Tailscale, or I2P overlays.

Overview

Section titled “Overview”

Wippy supports overlay networks that transparently carry traffic originating from functions, processes, and HTTP clients. Each overlay is a registry entry; code opts in per call, and the selection inherits to inner calls until a descendant explicitly overrides it.

Supported overlays:

  • network.socks5 — generic SOCKS5 proxy (also Tor’s SOCKS5 listener)
  • network.tailscale — tsnet overlay node
  • network.i2p — I2P SAM v3 bridge

Project Structure

Section titled “Project Structure”
netdemo/
├── wippy.lock
└── src/
    ├── _index.yaml
    └── probe.lua

Step 1: Define an Overlay

Section titled “Step 1: Define an Overlay”

Create src/_index.yaml:

version: "1.0"
namespace: app


entries:
  - name: processes
    kind: process.host
    lifecycle:
      auto_start: true


  - name: terminal
    kind: terminal.host
    lifecycle:
      auto_start: true


  # SOCKS5 proxy entry (Tor exposes one at 127.0.0.1:9050 by default)
  - name: tor
    kind: network.socks5
    host: 127.0.0.1
    port: 9050
    isolate_streams: true


  - name: probe
    kind: process.lua
    meta:
      command:
        name: probe
        short: Check outbound IP through overlays
    source: file://probe.lua
    method: main
    modules:
      - io
      - http_client
      - json

isolate_streams: true makes the SOCKS5 driver mint random credentials per connection so Tor opens a fresh circuit for each dial.

Step 2: Route Outbound Calls

Section titled “Step 2: Route Outbound Calls”

Create src/probe.lua:

local io = require("io")
local http_client = require("http_client")
local json = require("json")


local function fetch_ip(overlay)
    local options = { timeout = "15s" }
    if overlay then
        options.overlay_network = overlay
    end


    local resp, err = http_client.get("https://api.ipify.org?format=json", options)
    if err then
        return nil, tostring(err)
    end
    if resp.status_code ~= 200 then
        return nil, "HTTP " .. resp.status_code
    end


    local body = json.decode(resp.body or "")
    return body and body.ip, nil
end


local function main()
    local direct, d_err = fetch_ip(nil)
    if d_err then
        io.print("direct failed: " .. d_err)
    else
        io.print("direct IP: " .. direct)
    end


    local routed, r_err = fetch_ip("app:tor")
    if r_err then
        io.print("tor failed: " .. r_err)
    else
        io.print("tor IP:    " .. routed)
    end


    return 0
end


return { main = main }

The overlay_network option on http_client picks the overlay for that call only. Without it the dial goes through the process default (either network_service.default_network in .wippy.yaml or direct).

Step 3: Run It

Section titled “Step 3: Run It”
Terminal window
wippy init
wippy run probe

With Tor running locally:

direct IP: 203.0.113.42
tor IP:    185.220.101.61

If Tor is not running, the tor IP line will report a dial error — the SOCKS5 overlay does not silently fall back to a direct connection.

Inheritance

Section titled “Inheritance”

Overlay selection flows through nested calls. Pick the overlay once at a funcs.call or process.spawn edge and every inner HTTP call, nested funcs.call, and process.spawn underneath uses it until an explicit override:

local funcs = require("funcs")


local result, err = funcs.new()
    :with_options({ network = "app:tor" })
    :call("app:scrape_site", url)
local pid, err = process.with_options({ network = "app:tor" })
    :spawn_monitored("app.workers:probe", "app:processes")

The nested function or spawned process sees the overlay on every outgoing dial without passing it explicitly.

Binding a Listener

Section titled “Binding a Listener”

Overlays that support inbound traffic (Tailscale, I2P) can also accept HTTP listeners. Attach the overlay to the http.service instead of the client:

  - name: tailnet
    kind: network.tailscale
    hostname: wippy-node
    auth_key_env: TS_AUTHKEY
    ephemeral: true


  - name: gateway
    kind: http.service
    addr: ":8080"
    network: app:tailnet
    lifecycle:
      auto_start: true

The server binds on the tailnet interface; clients reach it via the Tailscale address. SOCKS5 is outbound-only — assigning it to http.service is rejected.

App-wide Default

Section titled “App-wide Default”

Set a default overlay in .wippy.yaml so every call uses it unless overridden:

network_service:
  state_dir: .wippy/net
  default_network: app:tor

Permissions

Section titled “Permissions”

The network.select action gates explicit overlay selection. Deny it on a scope to stop code from choosing an overlay:

  - name: deny_network
    kind: security.policy
    policy:
      actions: "network.select"
      resources: "*"
      effect: deny
    groups:
      - untrusted

Inherited overlays bypass this check — they were authorized at the caller’s edge. Only explicit re-selection at a Lua boundary is gated.

Next Steps

Section titled “Next Steps”