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Getting Started5
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Getting Started5
AI Agents4
App Builders1
Languages8
Platforms11
Popular Guides5
Utilities1

Static IP guide

Making API requests with a static IP from a Node app on Railway

Railway's shared NAT means your service's outbound IP isn't fixed, which breaks allowlisting for any API partner that checks the caller's address. Fixie gives your Node service a fixed pair of IPs instead: add FIXIE_URL under the service's Variables tab and route axios through it.

RuntimeNode.js and JavaScript
PlatformRailway
DestinationAPI allowlisting
Fixie productFixie HTTP/S proxy

Recommended setup

Use Fixie HTTP/S proxy for HTTP and HTTPS requests to an API, webhook provider, or service that allowlists outbound IP addresses. Store the proxy value in FIXIE_URL, then configure Node.js to route outbound traffic through Fixie before connecting to API allowlisting.

Set up Fixie on Railway

Create a Fixie HTTP/S proxy in the Fixie dashboard. Copy the proxy value into Railway Variables as FIXIE_URL, and copy the outbound IPs into the destination allowlist.

Implementation

The example below shows the core application-side change. Keep credentials in environment variables and avoid committing proxy, database, or API secrets.

Make an HTTP request through FIXIE_URL

const axios = require('axios');

const fixieUrl = new URL(process.env.FIXIE_URL);

axios.get('https://api.example.com/data', {
  proxy: {
    protocol: 'http',
    host: fixieUrl.hostname,
    // URL drops default ports, so fall back to 80 for Fixie's standard proxy port.
    port: Number(fixieUrl.port) || 80,
    auth: {
      username: fixieUrl.username,
      password: fixieUrl.password,
    },
  },
}).then((response) => {
  console.log(response.status);
});

Good to know

  • If more than one service in the project calls the same allowlisted API, expose FIXIE_URL to them as a Shared Variable instead of pasting the value into each service.
  • Changes made in the Variables tab are staged until you deploy; railway variable set FIXIE_URL=<proxy-url> from the CLI has the same effect.

Allowlist and test the static IPs

  1. Open the Fixie dashboard and copy the outbound IP addresses for this proxy.
  2. Add both IPs to the API provider.
  3. Deploy the updated Node.js app on Railway.
  4. Run a small connection test before sending production traffic.

Related guides

Related docs

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