{"id":54339,"library":"cats-core-2-13","title":"Cats Core (Scala 2.13)","description":"Core library for the Cats functional programming library for Scala, providing type classes and abstractions.","status":"active","version":"2.13.0","language":"java","source_language":null,"source_url":"https://github.com/typelevel/cats","tags":["functional-programming","scala","cats","type-classes"],"install":[{"cmd":"<dependency>\n  <groupId>org.typelevel</groupId>\n  <artifactId>cats-core_2.13</artifactId>\n  <version>2.13.0</version>\n</dependency>","lang":"xml","label":"Maven"},{"cmd":"implementation 'org.typelevel:cats-core_2.13:2.13.0'","lang":"groovy","label":"Gradle"}],"dependencies":[],"imports":[{"symbol":"IO","correct":"cats.effect.IO"}],"quickstart":{"code":"import cats.effect.IO\nimport cats.effect.unsafe.implicits.global\n\nobject Quickstart extends App {\n  val program = IO {\n    println(\"Hello, Cats!\")\n  }\n  program.unsafeRunSync()\n}","lang":"scala","description":"Minimal Cats Effect IO program that prints a message."},"warnings":[{"fix":"Ensure all Cats dependencies use the same major version (2.x) and recompile your project.","message":"Cats 2.x is not binary compatible with Cats 1.x; upgrading requires recompilation of dependent code.","severity":"breaking","affected_versions":">=2.0.0"}],"env_vars":null,"search_vec":"'2.13':4 'abstract':19 'cat':1,9,24 'class':17,27 'core':2,5 'function':10,21 'functional-program':20 'librari':6,12 'program':11,22 'provid':15 'scala':3,14,23 'type':16,26 'type-class':25","created_at":"2026-06-15T08:59:48.870894+00:00","updated_at":"2026-06-15T08:59:48.870894+00:00","problems":[],"ecosystem":"maven","meta_description":null,"install_score":null,"quickstart_score":null,"quickstart_tag":null,"pypi_latest":null,"cli_name":null,"cli_version":null,"type":"library","homepage":"https://typelevel.org/cats","github":"https://github.com/typelevel/cats","docs":"https://appdoc.app/artifact/org.typelevel/cats-core_2.13/","changelog":null,"pypi":null,"npm":null,"openapi_spec":null,"status_page":null,"smithery":null,"categories":["utility"],"base_url":null,"auth_type":null,"provenance":{"verified_status":null,"verified_at":null,"last_verified":"2026-06-15","next_check":"2026-12-12","install_tag":null}}