2021-03-03
3675
#node
Alexander Nnakwue
14680
Mar 3, 2021 â‹… 13 min read

Using ES modules in Node.js

Alexander Nnakwue Software engineer. React, Node.js, Python, and other developer tools and libraries.

Recent posts:

Fix over-caching with dynamic IO caching in Next.js 15

Next.js 15 caching overhaul: Fix overcaching with Dynamic IO and the use cache directive.

David Omotayo
Aug 6, 2025 â‹… 10 min read
LLMs are facing a QA crisis here’s how we could solve it

LLMs are facing a QA crisis: Here’s how we could solve it

LLM QA isn’t just a tooling gap — it’s a fundamental shift in how we think about software reliability.

Rosario De Chiara
Aug 4, 2025 â‹… 7 min read

Windsurf vs. Cursor: When to choose the challenger

Windsurf AI brings agentic coding and terminal control right into your IDE. We compare it to Cursor, explore its features, and build a real frontend project.

Chizaram Ken
Jul 31, 2025 â‹… 9 min read

The CSS if() function: Conditional styling will never be the same

The CSS Working Group has approved the if() function for development, a feature that promises to bring true conditional styling directly to our stylesheets.

Ikeh Akinyemi
Jul 30, 2025 â‹… 12 min read
View all posts

4 Replies to "Using ES modules in Node.js"

  1. What about the performance decrease because of the esm modules resolution? I experienced a noticeable difference in the startup between the 13.1 and 13.7 versions (around 20%). I find this huge since I’m not using this feature anywhere yet.

  2. Hello Gergo, I haven’t seen any real life overhead in terms of performance in the new ESM resolution algorithm. Can you point me to how you got the stat you have mentioned above, and since this is not a known issue in the wide, also peeking at the issues tab in the source code (https://github.com/nodejs/node/issues?q=is%3Aissue+is%3Aopen+esm) does not point any issues relating to performance… You can learn more about the ESM algorithm here on the docs, https://nodejs.org/api/esm.html#esm_resolution_algorithm

  3. Hi Alexander,
    Thanks for checking. I couldn’t create a trustworthy benchmark, that’s why I asked. Using 13.8 I don’t see any big differences now.

  4. So how can you _usefully_ import an ES module into a CommonJS module? You make mention of dynamic import but that’s asynchronous and can only be called inside a function which means you can’t import anything into the top level with it since no top level ‘await’.

    Without an elegant solution to that basic interoperability it seems quite painful. I’m not an experienced JS developer and just getting Jasmine to run some tests against an ES module seems like an almighty undocumented ballache. I’ve spent more time trying to make sense of this than actually doing any work!

Leave a Reply