Reserved Extensions

I’m thinking about how to add support for reserved extensions. These are extensions that one needs to depend on, but aren’t distributed via PGXN. Primarily, this means stuff distributed with the PostgreSQL core, including:

• PostgreSQL itself
• Bundled procedural languages (plpgsql, plperl, etc.)
• All contributed modules

Basically, anything that an extension might want to declare as a dependency, but that isn’t on PGXN itself.

There are a number of ways to do this. Which do you think would be the best approach?

1. Hard-code a list into the source code
2. Include an editable list in the runtime configuration file
3. Add a database table reserved for them and an API to edit it
4. Create a “pgdev” user and upload a distribution declaring all those extensions in a META.json file
5. Same as 4, but actually upload the PostgreSQL source

I’m leaning towards #2, perhaps having it automatically maintain a list in the database and a metadata file on the mirrors.

But what do you think? Opinions wanted!