{"id":63322,"library":"cats-effect-sjs1-2-12","title":"Cats Effect (Scala.js 1.x, Scala 2.12)","description":"Cats Effect is a purely functional runtime system for Scala, supporting asynchronous and concurrent programming.","status":"active","version":"3.7.0","language":"java","source_language":null,"source_url":"https://github.com/typelevel/cats-effect","tags":["functional","concurrency","scala","effect-system"],"install":[{"cmd":"<dependency>\n  <groupId>org.typelevel</groupId>\n  <artifactId>cats-effect_sjs1_2.12</artifactId>\n  <version>3.7.0</version>\n</dependency>","lang":"xml","label":"Maven"},{"cmd":"implementation 'org.typelevel:cats-effect_sjs1_2.12:3.7.0'","lang":"groovy","label":"Gradle"}],"dependencies":[],"imports":[{"symbol":"IO","correct":"cats.effect.IO"}],"quickstart":{"code":"import cats.effect.IO;\n\nIO<Object> program = IO.delay(() -> System.out.println(\"Hello\"));","lang":"java","description":"Creates an IO effect that prints a message."},"warnings":[{"fix":"Use cats-effect 3.x for Scala 2.13/3 and Scala.js 1.x.","message":"This version targets Scala.js 1.x and Scala 2.12; incompatible with Scala 2.13+ or Scala 3.","severity":"breaking","affected_versions":"<=3.7.0"}],"env_vars":null,"search_vec":"'1':4 '2.12':7 'asynchron':19 'cat':1,8 'concurr':21,24 'effect':2,9,27 'effect-system':26 'function':13,23 'program':22 'pure':12 'runtim':14 'scala':6,17,25 'scala.js':3 'support':18 'system':15,28 'x':5","created_at":"2026-06-17T16:42:31.823714+00:00","updated_at":"2026-06-17T16:42:31.823714+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://github.com/typelevel/cats-effect","github":"https://github.com/typelevel/cats-effect","docs":"https://appdoc.app/artifact/org.typelevel/cats-effect_sjs1_2.12/","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":"2026-06-17","next_check":"2026-12-14","install_tag":null}}