Similar to #10621 (native vm module support), this PR adds support for the native node:inspector module when the enable_nodejs_inspector_module compatibility flag is enabled.

Since inspector is marked as $experimental in workerd with no $impliedByAfterDate, this feature requires both the enable_nodejs_inspector_module and experimental compatibility flags to be set.

Implementation Comparison

Implementations are at:

• https://github.com/nodejs/node/blob/main/lib/internal/inspector.js
• https://github.com/unjs/unenv/blob/main/src/runtime/node/inspector.ts
• https://github.com/cloudflare/workerd/blob/main/src/node/inspector.ts

The three inspector implementations differ as follows:

Node.js (full implementation): Complete inspector support with native bindings, functional Session class for connecting to the V8 inspector, and Network APIs for broadcasting protocol events.

workerd (non-functional stub): Exports the expected API surface (Session, close, open, url, waitForDebugger, console, Network). Basic functions like close(), open(), url(), and waitForDebugger() are no-ops. The Session constructor and methods throw ERR_METHOD_NOT_IMPLEMENTED. Network methods also throw.

unenv (polyfill stub): Similar pattern to workerd - basic functions are no-ops, while Session and Network methods throw via notImplemented().

Since both workerd and unenv throw for Session and Network methods, there is no breaking change concern when switching to the native module.

Updates since last revision

• Added explicit check for experimental compatibility flag in getInspectorOverrides() to ensure the native module is only enabled when both enable_nodejs_inspector_module AND experimental flags are present (consistent with other experimental modules like wasi and dgram)

Human Review Checklist

• Verify flag names match workerd's compatibility-date.capnp
• Verify pattern matches other experimental modules (wasi)
• Tests include experimental flag as required
• Confirm tests only validate API surface (not actual inspector functionality, since workerd's inspector is a stub)
• Verify enabledByFlag checks for both module flag AND experimental flag

Devin PR requested by pbacondarwin@cloudflare.com (@petebacondarwin)
Link to Devin run: https://app.devin.ai/sessions/b61a9f009eec4b03850a418e63f16687

• Tests
  • Tests included/updated
  • Tests not necessary because:
• Public documentation
  • Cloudflare docs PR(s):
  • Documentation not necessary because: inspector is already documented as partially supported in the Workers docs