# lloydmeta/enumeratum

A type-safe, reflection-free, powerful enumeration implementation for Scala with exhaustive pattern match warnings and helpful integrations.

Repository: https://github.com/lloydmeta/enumeratum
Canonical: https://ross.abutalabs.com/products/enumeratum
Language: Scala
License: MIT
License Family: permissive
Topics: scala, enum, value-enum, enumerations, integrations
Last push: 2026-06-13T10:06:10+00:00

## Health v2 (maintenance only)
Score: 86/100 (v2, computed 2026-09-02T17:46:02.011165+00:00)
- activity 87, release rhythm 76, longevity 100
- inputs: {"age_days": 4289, "days_push": 81, "days_rel": 81, "gap_med": 33.5, "n_releases_24m": 11}
- flags: none
- formula: round(0.45*activity + 0.35*rhythm + 0.20*longevity); archived -> min(score, 10)

## Adoption (not part of the score)
Stars 1222, forks 151 (observed 2026-08-28T04:04:02.435347+00:00)

## What it is
Enumeratum is a type-safe, reflection-free enumeration library for Scala with exhaustive pattern match warnings and compile-time macro-based value collection. It supports ValueEnums with compile-time uniqueness constraints and integrates with popular Scala libraries like Play JSON, Circe, and Doobie.

## Use cases
- define type-safe enums in Scala without runtime reflection
- get exhaustive pattern match warnings for enum values
- create value enums mapping to Int, Long, or String with compile-time uniqueness checks
- serialize and deserialize enums with Play JSON, Circe, or other Scala JSON libraries
- use enums in Scala.js or Scala Native projects where reflection is unavailable
- store enums in a database via Doobie or Slick integrations

## When to choose
- you need type-safe enumerations in Scala with IDE-friendly idiomatic code
- your target platform lacks reliable reflection support (Scala.js, Scala Native, Android)
- you want compile-time validation of enum value uniqueness
- you need zero-dependency, performant enums faster than Scala's built-in Enumeration

## When to avoid
- you are not working in Scala
- you need Java-style enums with built-in JVM semantics
- your project uses Scala 3 and you cannot enable the -Yretain-trees compiler option for ValueEnums

## Facets
- artifact type: library
- maturity: stable
- function: serialization, developer-tools
- domain: programming-languages, developer-tools
- platform: jvm, cross-platform
- tags: scala, enumerations, value-enum, type-safe, macro, scala-js, scala-native

## Member repositories
- lloydmeta/enumeratum (main) score 86

## Provenance
- Observed fields: from GitHub, fetched 2026-08-28T04:04:02.435347+00:00.
- Health v2: computed from the inputs above; adoption is never an input.
- Inferred fields (summary, facets, guidance): AI-extracted, prompt v1, taxonomy v1, on 2026-08-30T06:15:38.093044+00:00, confidence not recorded.
  - readme: https://github.com/lloydmeta/enumeratum (fetched 2026-08-28T04:04:02.435347+00:00, sha 6fdd9e23a322)
- Data as of 2026-08-30T08:39:29.467469+00:00.