Scala Yaml


Scala Yaml is written in Scala, dependency-free library that allows to work with the YAML.

The goal of this project is to create idiomatic library which:

  • provides compile time type safety
  • semiautomatically derives codecs instances
  • have explicit error handling and helpful error messages
  • cross compiles to Scala.js and Scala Native (waiting for Scala 3 support in SN)

Please see the guide for more information

Help us create our roadmap!

Take part in our discussions, post your ideas, vote for feature requests and have a real impact on how our next milestone will look like!


import org.virtuslab.yaml.*

case class Address(city: String, zipcode: String) derives YamlCodec
case class Person(name: String, age: Int, address: Address) derives YamlCodec

val yaml = s"""name: John Wick
              |age: 40
              |  city: Anywhere
              |  zipcode: 12-345

val decoded =[Person]
// Either[YamlError, Person] = Right(Person(John Wick,40,Address(Anywhere,12-345)))

case class Activity(kind: String, distance: Seq[Double]) derives YamlCodec

val activity = Activity("running", Seq(5.37, 4.98, 5.73))
val encoded  = activity.asYaml
//kind: running
//  - 5.37
//  - 4.98
//  - 5.73