Modernizing packages to ESM

JS Party: JavaScript, CSS, Web Development

Mark Erikson (web dev professor/historian, OSS Maintainer & engineer at Replay) joins us to talk about the shift from CommonJS to ESM. We discuss the history of module patterns in JS and the grueling effort to push the world’s biggest developer ecosystem forward. Get ready to go to school kids, this one’s deep!

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Featuring:

• Mark Erikson – Website, GitHub, X
• Amal Hussein – GitHub, X

Show Notes:

• My Experience Modernizing Packages to ESM - Mark’s epic blog post
• History and Timeline of ES Modules
• Node API Reference for ESM
• Andrew Branch’s WIP TypeScript module processing documentation
• Sindre Sorhus: Pure ESM packages
• Modern Guide to Packaging a JS Library
• Guide for shipping ESM and CJS in one Package

Something missing or broken? PRs welcome!

Chapters

1. It's party time, y'all (00:00:00)

2. Welcoming back Mark (00:00:56)

3. A history lesson (00:03:28)

4. UMDs were hot ... (00:10:36)

5. History continued (00:11:49)

6. Enter TypeScript (00:16:59)

7. Publish as a Service (00:21:28)

8. Common pain points (00:22:51)

9. Sponsor: Changelog News (00:31:30)

https://changelog.com/news

10. Recapping the post (00:32:42)

11. Running multiple tests (00:44:22)

12. We need standards (00:51:51)

13. Parting thoughts (00:59:07)

14. Closing time (01:03:03)

15. Next up on the pod (Changelog++!) (01:04:06)

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