| name | moai-lang-scala |
| description | Scala 3.4+ development specialist covering Akka, Cats Effect, ZIO, and Spark patterns. Use when building distributed systems, big data pipelines, or functional programming applications.
|
| license | Apache-2.0 |
| compatibility | Designed for Claude Code |
| allowed-tools | Read Grep Glob mcp__context7__resolve-library-id mcp__context7__get-library-docs |
| user-invocable | false |
| metadata | {"version":"2.1.0","category":"language","status":"active","updated":"2026-01-11","modularized":"true","tags":"language, scala, akka, cats-effect, zio, spark, sbt"} |
| progressive_disclosure | {"enabled":true,"level1_tokens":100,"level2_tokens":5000} |
| triggers | {"keywords":["Scala","Akka","Cats Effect","ZIO","Spark",".scala",".sc","build.sbt","sbt"],"languages":["scala"]} |
Scala 3.4+ Development Specialist
Functional programming, effect systems, and big data processing for JVM applications.
Quick Reference
Auto-Triggers: Scala files (.scala, .sc), build files (build.sbt, project/build.properties)
Core Capabilities:
- Scala 3.4: Given/using, extension methods, enums, opaque types, match types
- Akka 2.9: Typed actors, streams, clustering, persistence
- Cats Effect 3.5: Pure FP runtime, fibers, concurrent structures
- ZIO 2.1: Effect system, layers, streaming, error handling
- Apache Spark 3.5: DataFrame API, SQL, structured streaming
Key Ecosystem Libraries:
- HTTP: Http4s 0.24, Tapir 1.10
- JSON: Circe 0.15, ZIO JSON 0.6
- Database: Doobie 1.0, Slick 3.5, Quill 4.8
- Streaming: FS2 3.10, ZIO Streams 2.1
- Testing: ScalaTest, Specs2, MUnit, Weaver
Module Index
This skill uses progressive disclosure with specialized modules:
Core Language
Effect Systems
- cats-effect.md - Cats Effect 3.5: IO monad, Resources, Fibers, FS2 Streaming
- zio-patterns.md - ZIO 2.1: Effects, Layers, ZIO Streams, Error handling
Frameworks
- akka-actors.md - Akka Typed Actors 2.9: Actors, Streams, Clustering patterns
- spark-data.md - Apache Spark 3.5: DataFrame API, SQL, Structured Streaming
Implementation Guide
Project Setup (SBT 1.10)
In build.sbt, set ThisBuild / scalaVersion to "3.4.2" and organization. Define lazy val root project with settings including name and libraryDependencies. Add dependencies for cats-effect, zio, akka-actor-typed, http4s-ember-server, circe-generic, and scalatest for test scope. Include scalacOptions for deprecation, feature warnings, and Xfatal-warnings.
Quick Examples
Extension Methods: Use extension keyword with parameter in parentheses. Define methods like words splitting on whitespace and truncate checking length before taking characters and appending ellipsis.
Given and Using: Define trait with abstract method signature. Create given instance with with keyword and implement the method. Create functions with using parameter clause for implicit resolution.
Enum Types: Define enum with generic type parameters and plus variance annotations. Create case entries with parameters. Define methods on enum using match expression to handle each case, returning appropriate results.
