How do I use pnpm instead of npm?

[ignoramous]

@poltava

because I have a build script in my package.json.

You can opt to write your own dockerfile and build the node app which ever way you want (yarn, deno bundle, bun compile, pnpm…)

Example: https://github.com/gregmsanderson/fly-hello-nodejs/blob/main/Dockerfile

Ref: How to override node version - #2 by greg