If your project has this:
scalaVersion := 2.11 // Replace '2.11' with the version of Scala your project is running on
Then you can use %%
to automatically get the version of the library compiled against the version of Scala the project is using:
libraryDependencies += "com.typesafe.slick" %% "slick" % "3.2.0-M1"
Note that having the above two lines is equivalent to having this one line:
libraryDependencies += "com.typesafe.slick" % "slick_2.11" % "3.2.0-M1"