A flex/bison inspired parser generator for Scala.

As an overview, the main 3 things that Slyce provides are:

• "slyce-generate" jar
• "slyce-parse" library
• "sylce-plugin" plugin

This can be downloaded from github releases.
It gives you a command line utility for generating parsers using slyce.
(It is definitely going to be less straight-forward than using the plugin).

# generate-help
java -jar slyce-generate-2.1.5.jar --help
# logger-help
java -jar slyce-generate-2.1.5.jar --help --
# basic usage
java -jar slyce-generate-2.1.5.jar generate all -s your-project-name/src/main

// project/plugins.sbt
addSbtPlugin("io.github.kalin-rudnicki" % "slyce-plugin" % "2.1.5")

// build.sbt
project
  .in(file("your-project-name"))
  .settings(
    // [your other settings]...
    slyceConfigs += SlyceConfig(SlyceInput.SrcDir, SlyceOutput.SrcDir),
  )

// build.sbt
project
  .in(file("your-project-name"))
  .settings(
    // [your other settings]...
    libraryDependencies += "io.github.kalin-rudnicki" %% "slyce-parse" % "2.1.5",
  )

You have a choice between using the command line utility or sbt plugin for generating your parsers, but adding slyce-parse as a dependency is required, as it is used by the generated files.
All slyce-_____ libraries depend on my own FP/utils library klib.

Setup sbt:

// project/plugins.sbt
addSbtPlugin("io.github.kalin-rudnicki" % "slyce-plugin" % "2.1.5")

// build.sbt
lazy val `your-project-name-parsers` =
    project
      .in(file("your-project-name-parsers"))
      .settings(
        // [your other settings]...
        libraryDependencies += "io.github.kalin-rudnicki" %% "slyce-parse" % "2.1.5",
        slyceConfigs += SlyceConfig(SlyceInput.SrcDir, SlyceOutput.SrcDir),
      )
lazy val `your-project-name` =
    project
      .in(file("your-project-name"))
      .dependsOn(
        `your-project-name-parsers`,
      )

Add slyce files:

project-root
|-- your-project-name-parsers
|   |-- src
|   |   |-- main
|   |   |   |-- slyce
|   |   |   |   |-- pkg1
|   |   |   |   |   |-- pkg2
|   |   |   |   |   |   |-- parsers
|   |   |   |   |   |   |   |-- Parser1.slf
|   |   |   |   |   |   |   |-- Parser1.sgf

Then run:

sbt slyce

Which will generate:

project-root
|-- your-project-name-parsers
|   |-- src
|   |   |-- main
|   |   |   |-- scala
|   |   |   |   |-- pkg1
|   |   |   |   |   |-- pkg2
|   |   |   |   |   |   |-- parsers
|   |   |   |   |   |   |   |-- Parser1.scala

If you notice here, we actually generated the files in your-project-name-parsers, instead of your-project-name. This is because the generated files can be relatively large, and something about them at the time being causes sbt to struggle a little bit (on the order of tens of seconds).
Adding it to a separate project will mean sbt will not have to worry about re-compiling them unless you re-generate them.
(as long as you're not putting any other code there).
At least from my testing, if it is in the same project as the code that is using it, it will have to be re-compiled every time.

Check out the wiki