Topics include:

04:01: Welcome to Node Dependency Hell.
14:00: How should the way we declare dependencies change if an addon is an implementation detail of another addon?
21:45: Can Ember CLI address these problems a layer above Yarn/npm?
23:25: Is JavaScript's fractured module ecosystem (CommonJS in node vs. ES6 modules in the frontend) contributing to the problem?
26:21: Someone's app broke when they installed their dependencies due to a Mirage dependency changing. How can we reliably solve this for users?
35:05: Even if the tooling were better, there's a cultural problem where JS library authors don't consider the dependencies they bring in.
39:04: Lessons learned:

apps should specify strict dependencies, libraries (including addons) should specify lenient dependencies
apps should use lockfiles
ember-dependency-lint & yarn resolutions are a good top-level escape hatch
addons should use the dependencies key & ember-auto-import for most of their dependencies


41:12: Ember Auto Import attempts some deduplication of dependencies. If you're writing an addon that has a dependency the host app cares a lot about, you can use addPackagesToProject to put the burden on host app.
48:33: Would you build Ember CLI Tailwind the same if you were building it from scratch today?
54:55: Call for input. What are any best practices that we've missed? What did we get wrong?
59:20: Mirage blog using GitHub issues teaser

Links:

Ember Auto Import
Discourse topic on conflicting dependencies
Dependency Lint
Ember CLI Addon Docs
Ember CLI Tailwind