scala

Guide Scala 3 engineering decisions for effect systems and HTTP frameworks.

16|Updated Apr 30, 2026
One-click install
npx skills add https://github.com/JCETools-Petra/JCE-Opencode-Tools --skill scala
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Please help me install this Agent Skill.
Skill: scala
Source: https://github.com/JCETools-Petra/JCE-Opencode-Tools/tree/main/config/skills/scala
Command: npx skills add https://github.com/JCETools-Petra/JCE-Opencode-Tools --skill scala

SYSTEM DOCUMENTATION & REQUIREMENTS

What problem does it solve?

Scala tasks frequently stall due to choosing the right effect system, HTTP framework, and safety patterns, leading to inconsistent architecture, brittle error handling, and harder-than-necessary testing.

Core Features & Use Cases

  • Effect-System Guidance (ZIO / Cats Effect / Akka / Direct Style): Choose an approach that matches your concurrency, dependency-injection, error modeling, and team conventions.
  • HTTP Framework Selection (Tapir / http4s / Play / zio-http / Vert.x): Build routes and endpoints that fit your streaming, type-safety, and full-stack needs.
  • Implementation & Review Verification Checklist: Validate compilation/tests, enforce type safety, manage resources, and confirm OpenAPI generation for Tapir workflows.
  • Use Case: You’re implementing a Scala 3 backend with typed errors, resource-safe DB access, and HTTP endpoints that should generate OpenAPI docs, while keeping concurrency behavior and testing strategy correct.

Quick Start

Use the scala skill to design a ZIO 2 + Tapir service in Scala 3.5 with typed errors, resource-safe DB access, and a verification plan that includes compile and test gates.

Frequently Asked Questions about scala

High-intent search queries and answers about installing and using this skill.

FAQPage Schema
How do I choose between ZIO, Cats Effect, and Akka typed for a Scala backend?

Choosing an effect system depends on your concurrency, dependency injection, and error modeling needs. This guidance maps project requirements to match ZIO, Cats Effect 3, or Akka Typed approaches for safer Scala development.

What is the best way to build HTTP endpoints in Scala 3 that generate OpenAPI docs?

Using Tapir is the best way to build type-safe HTTP endpoints that automatically generate valid OpenAPI documentation. This approach ensures endpoint definitions and API docs remain synchronized during Scala backend development.

How do I implement resource-safe database access with typed errors in Scala?

Implementing resource-safe database access requires effect-safe resource management patterns and typed error modeling. This ensures bracketed resources are properly released and errors are handled predictably within your chosen effect system.

Does this Scala guidance support http4s and zio-http for streaming workflows?

Yes, this guidance supports http4s and zio-http for streaming workflows. It helps you select an HTTP framework that fits your streaming requirements, type-safety constraints, and full-stack Scala architectural needs.

How do I verify sbt compilation and tests when refactoring Scala 3 code?

Verifying sbt compilation and tests requires a structured review checklist. This process confirms code compiles successfully, tests pass, type safety is enforced, and OpenAPI generation remains valid when using Tapir.

When should I use opaque types and union types in Scala 3?

Opaque types and union types should be used when you need zero-cost type abstractions and flexible error modeling in Scala 3. They are essential patterns for enforcing type safety without runtime overhead in effect systems.