CNB_BUILDPACK_DIR environment variable

[Malax]

Readable

[hone]

This is something I've seen a bunch of buildpacks do at Heroku. I'm curious of on the VMware/Pivotal side this is as common?

[sclevine]

This is also common on the CF side. My only request before approving would be that the env var be CNB_BUILDPACK_DIR to match project conventions.

We also may want to consider why an env var might be appropriate here vs. a positional arg like the other input directories.

[Malax]

@sclevine I renamed the variable, thanks! :)

We also may want to consider why an env var might be appropriate here vs. a positional arg like the other input directories.

I touched on that a little bit in the RFC, assuming we want to keep the amount of positional arguments low. It's harder to remember the order of argument than an actual name. That would be true for all other arguments though. What was the deciding factor to make CNB_STACK an env var and not an argument?

[nebhale]

I'm going to abstain from this RFC.

[hone]

We should make the RFC decision here independent of the positional argument/env var discussion IMO. Cleaning that up should be a separate RFC.

[sclevine]

In FCP as of 4/15