How to tag docker image with docker-compose

Question

I want to build image via docker-compose and set specific tag to it. Documentation says:

Compose will build and tag it with a generated name, and use

Answer 1

Original answer Nov 20 '15:

No option for a specific tag as of Today. Docker compose just does its magic and assigns a tag like you are seeing. You can always have some script call docker tag after you call docker-compose.

Now there's an option as described above or here

build: ./dir
image: webapp:tag