Well, it hurts that it isn't the default. The README still tells you to set the environment variable, it just isn't the "default" way to do things. In my opinion it would be better to entirely remove support for connecting to the database during compilation. Does anyone actually want to use it that way?

Comparing and contrasting, sqlc type checking happens via code generation, basically the only option in Go since there's nothing remotely like proc macros. Even with code generation, sqlc doesn't default to requiring an actual running instance of the database, though you can use an actual database connection (presumably this is useful if you're doing something weird that sqlc's internal model doesn't support, but even using PostgreSQL-specific features I hadn't really ran into much of this.)