[mattsse]

With NODE_USE_ENV_PROXY=1, loading the request transport can make Node 22 RPC/provider calls bypass the environment proxy. A key-free local reproduction succeeds with built-in fetch before importing current main's Undici 8.10.2, then fails with ENOTFOUND for an origin reachable only through the proxy.

Undici 8 initializes undici.globalDispatcher.2 with a plain Agent and replaces undici.globalDispatcher.1 with its compatibility wrapper. Node 22's built-in fetch uses the latter, so its existing EnvHttpProxyAgent is lost. This also affects viem's default HTTP transport.

Route the request transport's Undici imports through a small shim that captures the existing v1 dispatcher before initialization and restores it afterward. Explicit Undici request dispatchers and its v2 dispatcher remain independent. This preserves existing runtime proxy/custom-dispatcher configuration without changing the packaged Node version or TLS settings. The shim relies on Undici's shared dispatcher symbol; fresh-process tests cover that compatibility boundary.

Validation:

• Full macOS arm64 Node 22.22.3 suite: 302 tests across 23 files. GitHub Linux x64 Node 22.23.3 CI also passes all 302 tests, code/types, changelog, dependency scan, and aggregate checks.
• Six fresh-process regressions pass on Node 22.22.3 and Node 24.19.0: built-in fetch and viem through a local proxy, NO_PROXY bypass, proxy opt-in disabled, explicit Undici proxy use, and custom legacy dispatcher preservation. Disabling restoration reproduces the proxy and custom-dispatcher failures.
• Repository code checks, source/test type checks, TypeScript build, and changelog validation pass.
• pnpm package builds the request binary; --version smoke test passes. A loopback proxy harness loads the actual bundled CLI using PKG_EXECPATH=PKG_INVOKE_NODEJS: RPC fetch retains the original dispatcher and succeeds under both the SHA-256-verified v0.11.0 release's Node 22.22.3 runtime and the newly built Node 22.23.2 runtime.
• Control: latest raw Undici import breaks proxy routing under the official Node 22.22.3 runtime; Node 24.19.0 retains routing.

Supplemental validation in the original cloud environment at exact PR commit 9cf4e0c8794af1202b67846bb77a019109dcaf44:

• The bundled Node 22.22.3 runtime reaches the public RPC and returns chain ID 4217 before importing raw Undici 8.10.2, then fails with EAI_AGAIN after that import. Loading the fixed request module preserves the existing dispatcher and the public RPC again returns chain ID 4217.
• Node 24 succeeds before and after import, and all six proxy regression tests pass on Node 24 in the original cloud environment.
• The official Linux packaging script successfully builds tempo-request. An isolated empty-home dry-run against the public RPC returns chain ID 4217. A separate packaged fixed-module viem probe under Node 22.23.2 also returns chain ID 4217.
• Source and test type checks pass. The full cloud suite has 283 passed and 19 failed, with failures caused by missing sqlite3 (spawn sqlite3 ENOENT and downstream session assertions); the cloud full suite is not green. The macOS and GitHub Linux CI suites above still pass all 302 tests.
• Vitest workers are unsupported under the old bundled Node 22 runtime because of --require; direct packaged probes were used for that runtime.

The automated loopback proxy fixture uses HTTP and a reserved .invalid origin; the supplemental public RPC probes cover the original cloud network path. No credentials or payment operations were used, and existing runtime wrappers were not changed.