Remove NYM mixFetch per-host queue

CHANGELOG.md

@@ -2,6 +2,8 @@
 
 ## Unreleased
 
+- changed: Remove NYM mixFetch per-host request queue now that `@nymproject/mix-fetch` handles concurrency natively.
+
 ## 2.43.1 (2026-02-23)
 
 - changed: Upgrade `@nymproject/mix-fetch` to improve performance with new concurrency changes.

src/io/browser/browser-io.ts

@@ -51,7 +51,6 @@ export function makeBrowserIo(logBackend: LogBackend): EdgeIo {
       if (privacy === 'nym') {
         // Ensure mixFetch is initialized before use
         await initMixFetch(log)
-        // Use queued fetch to handle mixFetch's one-request-per-host limitation
         return await queueMixFetch(uri, {
           ...opts,
           mode: 'unsafe-ignore-cors' as RequestMode

src/io/react-native/react-native-worker.ts

@@ -178,7 +178,6 @@ async function makeIo(logBackend: LogBackend): Promise<EdgeIo> {
       if (privacy === 'nym') {
         // Ensure mixFetch is initialized before use
         await initMixFetch(log)
-        // Use queued fetch to handle mixFetch's one-request-per-host limitation
         const response = await queueMixFetch(uri, {
           ...opts,
           mode: 'unsafe-ignore-cors' as RequestMode

src/util/nym.ts

@@ -17,24 +17,6 @@ export const mixFetchOptions: SetupMixFetchOps = {
 // MixFetch initialization state
 let mixFetchInitPromise: Promise<IMixFetch> | null = null
 
-// Per-host request queue to handle mixFetch's one-request-per-host limitation
-// Maps host -> Promise that resolves when current request completes (for chaining)
-const hostRequestChains = new Map<string, Promise<Response>>()
-
-/**
- * Extract the host:port from a URI for queue keying
- */
-function getHostKey(uri: string): string {
-  try {
-    const url = new URL(uri)
-    const port =
-      url.port !== '' ? url.port : url.protocol === 'https:' ? '443' : '80'
-    return `${url.hostname}:${port}`
-  } catch {
-    return uri
-  }
-}
-
 /**
  * Initialize the NYM mixFetch client. Must be called before using mixFetch.
  * Safe to call multiple times - subsequent calls return the same promise.
@@ -58,31 +40,11 @@ export async function initMixFetch(log: EdgeLog): Promise<IMixFetch> {
 }
 
 /**
- * Queue-wrapped mixFetch that serializes requests per host.
- * mixFetch only allows one concurrent request per host, so we chain them.
+ * Thin wrapper around mixFetch with pre-configured options.
  */
 export async function queueMixFetch(
   uri: string,
   opts: RequestInit & { mode?: string }
 ): Promise<Response> {
-  const hostKey = getHostKey(uri)
-
-  // Get the current chain for this host (or resolved promise if none)
-  const previousChain = hostRequestChains.get(hostKey) ?? Promise.resolve()
-
-  // Chain our request after the previous one
-  const ourWork = previousChain
-    .catch(() => {}) // Ignore errors from previous request
-    .then(async () => await mixFetch(uri, opts, mixFetchOptions))
-    .finally(() => {
-      // Clean up if we're still the chain tail
-      if (hostRequestChains.get(hostKey) === ourWork) {
-        hostRequestChains.delete(hostKey)
-      }
-    })
-
-  // Store our chain BEFORE awaiting - ensures subsequent requests wait for us
-  hostRequestChains.set(hostKey, ourWork)
-
-  return await ourWork
+  return await mixFetch(uri, opts, mixFetchOptions)
 }