Using alpine as default

[webysther]

Is more secure to add suffix -alpine for docker optimized for this dist. My suggest is change tag to exists the normal version and the alpine version as PHP, Node and a bunch of official images.

[alcohol]

There is no need for that. Our official image is aimed at quick throw-away commands. If you need an image that supports exactly your target environment, you should create that image, and simply copy Composer from our image into yours, using the (relatively new) multistage build approach.

[webysther]

I don't really need a image to target environment, just ask to keep the same pattern to create tag like other projects.

[alcohol]

Sure, if we actually offered multiple flavours that would make sense and I would agree.
But we do not offer that. So there is no need for additional tagging.