I’m surprised to see this using a `--require` hook (rather than `--import`). Maybe something’s changed significantly since I was looking into building some similar functionality… but it makes me wonder about nuances in nub’s ESM support.

(When I was investigating this it was very early in Node’s `--import` story, but there were several edge cases with the more common ESM-to-CJS approaches that I wanted to address. Most were probably exceedingly niche concerns, but I’d expect top-level await to affect a meaningful subset of users.)

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colinmcd 2 hours ago | parent [-]

We use this to register our preload purely for performance reasons. In this and many other cases CommonJS is still faster than ESM. Using --require is about 0.5ms overhead vs 4.6ms for --import (on my M1 Macbook Pro).

Relatedly Node.js recently (2025) introduced a synchronous version of its resolver hook registration API (`module.registerHooks()`) specifically to improve performance over the old async `module.register()` API. It was a big unblocker for Nub. For the interested, the async API added 19ms fixed registration overhead + about 130us additional overhead per import.

Which flag Nub uses here doesn't impact userland at all, TLA is supported wherever it's supported by Node.js itself.

	▲	eyelidlessness 8 minutes ago \| parent [-]
		Thanks! From what you say here and what I see in the docs, it looks like everything is much simpler and more robust than when I was exploring the space. I’m happy to see that, and thrilled it’s mature enough now to support use cases like nub.