Migrating from v1.x

v2 is a clean break. The package no longer ships a Go-WASM HTTP/TLS client or a SOCKS5-shaped Network Requester request; it routes through the shared mix-tunnel and exits at an IPR. If you're starting fresh, you don't need this page; see mix-fetch.

Removed packages

The five-variant publish (@nymproject/mix-fetch, mix-fetch-full-fat, mix-fetch-commonjs, mix-fetch-commonjs-full-fat, mix-fetch-node-commonjs) is gone. There is one package, ESM only:

The single v2 package is ESM-only and always inlines its wasm (the v1 full-fat behaviour is now the default), so there is no separate bundler-config step. CommonJS and Node builds are not shipped. The Node build in particular is not just a packaging variant: the mixnet transport runs on browser globals (WebSocket, Web Worker) inside the wasm, so a Node target would need a runtime-compatibility layer, not a CommonJS rebuild. If you need a CJS or Node variant, open an issue describing the use case.

Removed options

The v1 setup options bag covered Network Requester selection and gateway tuning. v2 replaces it with the smolmix SetupMixTunnelOpts surface:

Removed request-init flags

The v1 mode: 'unsafe-ignore-cors' flag is gone. v2 doesn't perform browser-side CORS checks at all (see Drop-in caveats), so the flag has no meaning.

New setup

// v1
import { createMixFetch } from '@nymproject/mix-fetch-full-fat';
const mixFetch = await createMixFetch({
  clientId: 'my-app',
  preferredGateway: 'q2A2cbooyC16YJzvdYaSMH9X3cSiieZNtfBr8cE8Fi1',
  mixFetchOverride: { requestTimeoutMs: 60_000 },
  forceTls: true,
});
 
// v2
import { createMixFetch } from '@nymproject/mix-fetch';
const mixFetch = await createMixFetch({
  // Optional: pin an exit IPR instead of an entry gateway.
  // preferredIpr: '...',
});

Architectural change

v1 ran two WASM modules: a Go module with crypto/tls + Mozilla CA bundle, and a Rust module handling Nym's Socks5Request framing to a Network Requester exit. v2 runs one WASM module (smolmix-wasm (opens in a new tab)) with a userspace TCP/IP stack (smoltcp (opens in a new tab)) and rustls for TLS. The exit is an IPR, not a Network Requester.

Consequences:

• One WASM module, smaller bundle. v1's Go runtime accounted for ~6 MB of the full-fat bundle; v2 drops it.
• Shared infrastructure with mix-dns and mix-websocket. The same tunnel handles all three.
• IPR exit policies apply. What was allowed by your previous Network Requester may not be allowed by your default IPR, which applies the current Nym exit policy (opens in a new tab).