Ergonomic, hermetic, user-friendly software build system for Python, Go, Java, Kotlin, Protobuf, Scala, Shell. Pants lets you fearlessly scale up your codebase!

Pants

or simpler approach: this log seems to be saying that pants invoked zinc on target B but zinc didn't rebuild anything.

```
                   [1/2] Compiling 1 zinc source in 1 target (src/main/scala/A:A).
13:58:11 00:02       [compile]

13:58:11 00:02         [zinc]
                       [info] Compiling 1 Scala source to /Users/awinter/tuts/increment/.pants.d/compile/zinc/c95338cea9cc/src.main.scala.A.A/current/classes...
                       [info] Compile success at Sep 13, 2017 1:58:11 PM [0.559s]

                   [2/2] Compiling 1 zinc source in 1 target (src/main/scala/B:B).
13:58:11 00:02       [compile]

13:58:11 00:02         [zinc]
                       [info] Compile success at Sep 13, 2017 1:58:11 PM [0.015s]
```