ts-code-mode-web

TanStack AI Code Mode web example using React and TanStack Start.

Setup

Prerequisites

• Node.js >=18
• pnpm@10.17.0
• Xcode Command Line Tools (macOS)

Installation

pnpm install

Rebuilding isolated-vm (native module)

@tanstack/ai-isolate-node depends on isolated-vm, a native Node.js addon that must be compiled from source when a prebuilt binary is not available for your Node.js version.

When is this needed?

The isolated-vm package ships prebuilt binaries for select Node.js ABI versions. If you are running a newer Node.js version whose ABI is not yet included (e.g. Node.js 25.x / ABI 141), you will see an error like:

Error: No native build was found for platform=darwin arch=arm64 runtime=node abi=141 ...
    loaded from: .../isolated-vm

How to fix it

1. Ensure Xcode Command Line Tools are installed (macOS):

   xcode-select --install

2. Run node-gyp via npx inside the isolated-vm package directory (from the monorepo root):

   ISOLATED_VM_DIR="node_modules/.pnpm/isolated-vm@6.1.0/node_modules/isolated-vm"
   cd "$ISOLATED_VM_DIR" && npx node-gyp rebuild

   Or as a one-liner from the monorepo root (/Users/jherr/tanstack/ai/code-mode):

   cd node_modules/.pnpm/isolated-vm@6.1.0/node_modules/isolated-vm && npx node-gyp rebuild

3. A successful build ends with gyp info ok and produces build/Release/isolated_vm.node.

Notes

• Linker warnings about macOS version mismatches (building for macOS-11.0, but linking with dylib ... built for newer version) are harmless and can be ignored.
• The compiled .node file lives in the pnpm content-addressable store and will need to be rebuilt after pnpm install --force or after upgrading Node.js to a different ABI version.
• Python 3 is required by node-gyp. It is detected automatically from $PATH.

Node.js 25 + isolated-vm runtime crash (SIGSEGV)

Even after successfully compiling from source, isolated-vm@6.1.0 crashes the server process (exit code 139, SIGSEGV) when run under Node.js 25.x. This is a V8 API incompatibility — Node 25 ships V8 14.1 whose internal C++ API has changed in ways that break isolated-vm's isolate creation code at runtime.

Symptom: The server dies silently with no JavaScript error or log output when the first code mode request is made.

Fix applied: All server routes in this example have been switched from the node isolate driver to the quickjs driver (@tanstack/ai-isolate-quickjs), which is a pure-JS sandbox with no native addon dependency and works on any Node.js version.

When isolated-vm works again: Once isolated-vm publishes a release compatible with Node 25 / V8 14.1, switch the driver back to 'node' in src/lib/create-isolate-driver.ts (default) and in each API route file. The node driver provides stronger isolation (true V8 process boundary) and is preferred in production.

Development

pnpm dev   # starts the Vite dev server on port 3001

Build

pnpm build