[ef4]

It's much more robust to have a dedicated build step that is separate from your deploy step.

The build step is where you install deps, do compilation, etc. Then it saves the output. The deploy step can just copy all the files from the last known good build to the new/updated servers.

This way you can always deploy a last-known-good release quickly and without external dependencies.

It also lets you take advantage of package caching on the build server so that as long as your deps don't change, you can deploy new releases to old or new servers without hitting any external services.