[go: up one dir, main page]

Java Functional programming

Open-source Java projects categorized as Functional programming
Edit details
Java Monad Optics Monoid HacktoberFest
Stream - Scalable APIs for Chat, Feeds, Moderation, & Video.
Stream helps developers build engaging apps that scale to millions with performant and flexible Chat, Feeds, Moderation, and Video APIs and SDKs powered by a global edge network and enterprise-grade infrastructure.
getstream.io
featured

Top 22 Java Functional programming Projects

Java logo
Functional programming

  1. Javaslang

    vÊŒvr (formerly called Javaslang) is a non-commercial, non-profit object-functional library that runs with Java 8+. It aims to reduce the lines of code and increase code quality.

    Project mention: Vavr 0.10.6 Released | news.ycombinator.com | 2025-03-10

  2. InfluxDB

    InfluxDB – Built for High-Performance Time Series Workloads. InfluxDB 3 OSS is now GA. Transform, enrich, and act on time series data directly in the database. Automate critical tasks and eliminate the need to move data externally. Download now.

    InfluxDB logo

  3. groovy

    Apache Groovy: A powerful multi-faceted programming language for the JVM platform

    Project mention: Continuous integration with containers and inceptions | dev.to | 2025-11-10

    Jenkins provides a nice way to bundle pipelines definitions, among other actions, using shared libraries. Those are basically Groovy scripts and exist to extend Jenkins functionality.

  4. Functional Java

    Backport of Java 8's lambda expressions to Java 7, 6 and 5

  5. StreamEx

    Enhancing Java Stream API

  6. jOOλ

    jOOλ - The Missing Parts in Java 8 jOOλ improves the JDK libraries in areas where the Expert Group's focus was elsewhere. It adds tuple support, function support, and a lot of additional functionality around sequential Streams. The JDK 8's main efforts (default methods, lambdas, and the Stream API) were focused around maintaining backwards compatibility and implementing a functional API for parallelism.

  7. functionaljava

    Functional programming in Java

  8. cyclops-react

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

  9. Stream

    Stream - Scalable APIs for Chat, Feeds, Moderation, & Video. Stream helps developers build engaging apps that scale to millions with performant and flexible Chat, Feeds, Moderation, and Video APIs and SDKs powered by a global edge network and enterprise-grade infrastructure.

    Stream logo

  10. λ

    Functional patterns for Java

  11. derive4j

    Java 8 annotation processor and framework for deriving algebraic data types constructors, pattern-matching, folds, optics and typeclasses.

  12. underscore-java

    java port of Underscore.js

  13. protonpack

    Stream utilities for Java 8

  14. throwing-function

    Checked Exceptions-enabled Java 8+ functional interfaces + adapters

  15. Faux Pas

    A library that simplifies error handling for Functional Programming in Java

  16. purefun

    Functional Programming library for Java

  17. noexception

    Java library for handling exceptions in concise, unified, and architecturally clean way.

  18. fuzion

    The Fuzion Language Implementation (by tokiwa-software)

  19. expressible

    Utility library dedicated for functional & non-functional codebases to simplify modelling of success and failure responses for Java/Kotlin 🔀

  20. packrat

    Gatherers library for Java Stream API

  21. stork

    minimalistic functional programming language (by maciejmikosik)

  22. FunctionalUtils

    A set of utilities to help with functional programming in Java providing the most useful monads and tools to get you started.

  23. keycloak-auth-service

    Auth-Service using Keycloak for authentication, built with Java WebFlux and functional programming, includes noti-service for sending emails and messages.

    Project mention: Introducing Java Library for Backend Microservice Webflux (Reactor-core) | dev.to | 2025-01-11

    reactify-core library for webflux microservice project: keycloak-auth-service

  24. roman-arabic-calculator

    This code is a proof of concept. The calculator can work with both Arabic (1,2,3,4,5 ...) and Roman (I, II, III, IV, V ...) numbers.

  25. SaaSHub

    SaaSHub - Software Alternatives and Reviews. SaaSHub helps you find the best software and product alternatives

    SaaSHub logo
NOTE: The open source projects on this list are ordered by number of github stars. The number of mentions indicates repo mentiontions in the last 12 Months or since we started tracking (Dec 2020).

Java Functional programming discussion

Log in or Post with

Java Functional programming related posts

Index

What are some of the best open-source Functional programming projects in Java? This list will help you:

# Project Stars
1 Javaslang 6,034
2 groovy 5,406
3 Functional Java 3,527
4 StreamEx 2,275
5 jOOλ 2,116
6 functionaljava 1,619
7 cyclops-react 1,332
8 λ 877
9 derive4j 576
10 underscore-java 547
11 protonpack 485
12 throwing-function 388
13 Faux Pas 140
14 purefun 133
15 noexception 122
16 fuzion 55
17 expressible 31
18 packrat 23
19 stork 6
20 FunctionalUtils 6
21 keycloak-auth-service 6
22 roman-arabic-calculator 0

Sponsored
InfluxDB – Built for High-Performance Time Series Workloads
InfluxDB 3 OSS is now GA. Transform, enrich, and act on time series data directly in the database. Automate critical tasks and eliminate the need to move data externally. Download now.
www.influxdata.com

Did you know that Java is
the 9th most popular programming language
based on number of references?

Loading...