# AOL-archive/cyclops

An advanced, but easy to use, platform for writing functional applications in Java 8.

Repository: https://github.com/AOL-archive/cyclops
Canonical: https://ross.abutalabs.com/products/aol-archive-cyclops
Language: Java
License: Apache-2.0
License Family: permissive
Topics: functional-programming, reactive-streams, monoid, streams, collections, data-structures, monad, monad-transformers, reactive, asynchronous, java8, streams-api, java
Last push: 2023-03-21T11:08:31+00:00

## Health v2 (maintenance only)
Score: 23/100 (v2, computed 2026-09-03T02:20:16.233290+00:00)
- activity 0, release rhythm 8, longevity 100
- inputs: {"age_days": 4243, "days_push": 1261, "days_rel": null, "gap_med": null, "n_releases_24m": 0}
- flags: none
- formula: round(0.45*activity + 0.35*rhythm + 0.20*longevity); archived -> min(score, 10)

## Adoption (not part of the score)
Stars 1327, forks 134 (observed 2026-08-28T04:04:22.886952+00:00)

## What it is
Cyclops is a functional programming library for Java 8+ providing advanced purely functional data structures, monads, monad transformers, and reactive streams integration. It offers an easy-to-use API for functional and asynchronous application development on the JVM.

## Use cases
- write functional code in Java
- use monads like Option, Either, and Try in Java
- work with immutable persistent collections
- process streams reactively and asynchronously
- avoid nulls and exceptions with functional error handling
- lazy evaluation with Eval
- structural pattern matching in Java

## When to choose
- you want functional programming abstractions on the JVM
- you need type-safe alternatives to Optional and exceptions
- you want reactive streams with functional data structures

## When to avoid
- you are on a modern Java codebase already using standard streams and records
- you prefer lightweight single-purpose libraries
- you need a library under very active development

## Facets
- artifact type: library
- maturity: maintenance
- function: serialization, streaming, concurrency
- domain: developer-tools, programming-languages
- platform: jvm
- tags: functional-programming, monads, reactive-streams, immutable-collections, pattern-matching, java8, algorithms

## Member repositories
- AOL-archive/cyclops (main) score 23

## Provenance
- Observed fields: from GitHub, fetched 2026-08-28T04:04:22.886952+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 2026-08-30T04:46:03.557650+00:00, confidence not recorded.
  - readme: https://github.com/AOL-archive/cyclops (fetched 2026-08-28T04:04:22.886952+00:00, sha 5943a4f42a68)
- Data as of 2026-08-30T08:39:29.467469+00:00.