I haven't used --filter much. I see the ... documented here, but isn't this also default behavior? Or is it not default behavior when --filter is used?

Yea good question, it's a little confusing, but there is a difference. However in practice it’s not usually applicable. Say you only have this in your turbo.json (no depends on):

"build": {
   "outputs": ["dist/**", ".next/**"]
 }

In this case, you will get different results depending on the filter.
For example:
turbo build --filter={app} will only build {app}.
But,
turbo build --filter={app}... will build {app} , and any workspace dependency listed in {app}’s package.json

However, if you had (the more common):

"build": {
   "dependsOn": ["^build"],
   "outputs": ["dist/**", ".next/**"]
 }

--filter={app} and --filter={app}... are going to behave the same.

ahhh, thanks for that explanation, that makes sense