Top 23 Scala Open-Source Projects

  • Apache Spark

    Apache Spark - A unified analytics engine for large-scale data processing

    Project mention: Integrate Pyspark Structured Streaming with confluent-kafka | | 2023-08-12

    Apache Spark -

  • Apache Kafka

    Mirror of Apache Kafka

    Project mention: Implementing tagged fields for Kafka Protocol | /r/apachekafka | 2023-05-27
  • InfluxDB

    Collect and Analyze Billions of Data Points in Real Time. Manage all types of time series data in a single, purpose-built database. Run at any scale in any environment in the cloud, on-premises, or at the edge.

  • scala

    Scala 2 compiler and standard library. Bugs at; Scala 3 at

    Project mention: Functional Programming Library for Golang by IBM | | 2023-08-17

    Big Scala vibes here, see also [1].


  • lila

    ♞ the forever free, adless and open source chess server ♞

    Project mention: Guess my elo from this match | /r/chess | 2023-10-18

    [Event "Rated Blitz game"] [Site ""] [Date "2023.10.16"] [White "me"] [Black "opponent"] [Result "1-0"] [UTCDate "2023.10.16"] [UTCTime "19:55:12"] [WhiteElo "1067"] [BlackElo "979"] [WhiteRatingDiff "+5"] [BlackRatingDiff "-7"] [Variant "Standard"] [TimeControl "180+0"] [ECO "B00"] [Opening "Pirc Defense"] [Termination "Normal"] [Annotator ""] 1. e4 d6 { B00 Pirc Defense } 2. Bc4?! { (0.75 → 0.00) Inaccuracy. d4 was best. } (2. d4 Nf6 3. Nc3 e5 4. Nf3 Nbd7 5. Bc4 Be7 6. O-O O-O) 2... Nf6 3. Qf3 c6 4. b4?! { (-0.21 → -1.19) Inaccuracy. Bb3 was best. } (4. Bb3 e5 5. Ne2 Be7 6. d4 O-O 7. Nbc3 a5 8. a4 Na6) 4... b5?! { (-1.19 → -0.62) Inaccuracy. d5 was best. } (4... d5 5. exd5 cxd5 6. Bb5+ Bd7 7. Bxd7+ Nbxd7 8. Qb3 e5 9. Ne2 Bd6 10. O-O O-O 11. d3) 5. Bb3 Na6?! { (-0.63 → 0.31) Inaccuracy. a5 was best. } (5... a5 6. bxa5) 6. e5 dxe5?? { (0.48 → 3.21) Blunder. Nd5 was best. } (6... Nd5 7. a4 dxe5 8. axb5 Naxb4 9. c3 Bg4 10. Qe4 e6 11. cxb4 Bf5 12. Bxd5 Bxe4 13. Bxe4) 7. Qxc6+ Nd7?! { (3.13 → 4.34) Inaccuracy. Bd7 was best. } (7... Bd7 8. Qxa6 e6 9. Nc3 Bxb4 10. a4 bxa4 11. Bxa4 O-O 12. Bxd7 Qxd7 13. Nge2 Rfb8 14. O-O) 8. Qxa8 Nxb4 9. Qxa7 Nxc2+?! { (3.60 → 5.54) Inaccuracy. e6 was best. } (9... e6 10. Ba3 Bc5 11. Qa8 O-O 12. Bxb4 Bxb4 13. Qe4 Bc5 14. Ne2 Qb6 15. Qh4 Nf6 16. Nbc3) 10. Bxc2 Nc5?! { (5.41 → 8.97) Inaccuracy. e6 was best. } (10... e6 11. Nf3 Bc5 12. Qa8 Qc7 13. O-O O-O 14. Na3 b4 15. Nc4 Bb7 16. Qa5 Qc8 17. Bb2) 11. Qxc5 g6 12. Qxb5+ Bd7 13. Qxe5 f6 14. Qe3 e5 15. Nf3 Bd6 16. O-O g5 17. Ba3 Bxa3 18. Nxa3 g4 19. Nxe5 fxe5 20. Qxe5+ Kf7 21. f3 Qe8?! { (12.07 → Mate in 5) Checkmate is now unavoidable. g3 was best. } (21... g3 22. Bb3+ Kg6 23. Qxg3+ Kh6 24. Qd6+ Kg7 25. Rac1 Re8 26. Qd4+ Kg6 27. g4 Be6 28. Qxd8) 22. fxg4+ Kg8 23. Qg5+ Qg6 24. Bxg6 hxg6 25. Qxg6# { White wins by checkmate. } 1-0

  • Deeplearning4j

    Suite of tools for deploying and training deep learning models using the JVM. Highlights include model import for keras, tensorflow, and onnx/pytorch, a modular and tiny c++ library for running math code and a java based math library on top of the core c++ library. Also includes samediff: a pytorch/tensorflow like library for running deep learning using automatic differentiation.

  • Play

    The Community Maintained High Velocity Web Framework For Java and Scala.

    Project mention: Play Framework 2.9.0 Release Candidate | | 2023-09-20
  • Onboard AI

    Learn any GitHub repo in 59 seconds. Onboard AI learns any GitHub repo in minutes and lets you chat with it to locate functionality, understand different parts, and generate new code. Use it for free at

  • kafka-manager

    CMAK is a tool for managing Apache Kafka clusters

    Project mention: FLaNK Stack Weekly 16 October 2023 | | 2023-10-17
  • milewski-ctfp-pdf

    Bartosz Milewski's 'Category Theory for Programmers' unofficial PDF and LaTeX source

    Project mention: Category Theory for Programming | | 2023-11-06

    Strangely similar name to the well-known 'Category Theory for Programmers'

  • mal

    mal - Make a Lisp

    Project mention: Ask HN: Is Lisp Simple? | | 2023-08-21

    >Would be interesting to see how the interpreter works actually...

    It's quite easy to see, there are interpeters for Lisp in like 20 lines or so.

    Here's a good one:

    (It has the full code in a link towards the bottom)

    There's also this:

  • awesomo

    Cool open source projects. Choose your project and get involved in Open Source development now.

    Project mention: Anything C can do Rust can do Better | | 2022-12-01

    See repos kud1ing/awesome-rust & awesomo /rust

  • Gitbucket

    A Git platform powered by Scala with easy installation, high extensibility & GitHub API compatibility

    Project mention: Anyway to build my own github server at home for private use? I have hundreds of apps and want to keep them private | /r/github | 2023-04-27

    Gitbucket (

  • awesome-scala

    A community driven list of useful Scala libraries, frameworks and software.

    Project mention: I had a great experience with Scala and hopefully it will get more popular | /r/scala | 2023-07-11

    last, resources :) if you are still missing something, try looking on the Scaladex or Scala list of awesome which also links to lot of learning material

  • Finagle

    A fault tolerant, protocol-agnostic RPC system

    Project mention: Features of Project Loom incorporated in Java 21 | | 2023-08-15

    Not sure about now but a few years back the company I worked for was heavily vested in Finagle [1] using Future pools. I'm sure virtual threads would only enhance this framework. Also, Spring and it's reactive webflux would probably benefit as well [2].



  • Zeppelin

    Web-based notebook that enables data-driven, interactive data analytics and collaborative documents with SQL, Scala and more.

  • Gatling

    Modern Load Testing as Code

    Project mention: Best Practices in Testing GraphQL APIs | | 2023-07-03

    Performance and load testing are essential parts of GraphQL API testing. It ensures APIs can handle expected traffic volumes and respond within acceptable timeframes. You can use tools like Apache JMeter or Gatling to generate realistic loads and evaluate the API's performance under different scenarios. Techniques like batched queries and caching can help mitigate this issue.

  • dotty

    The Scala 3 compiler, also known as Dotty.

    Project mention: RustRover – A Standalone Rust IDE by JetBrains | | 2023-09-13

    Dotty? Was it still the name later?

  • papermill

    📚 Parameterize, execute, and analyze notebooks

    Project mention: Jupyter Kernel Architecture | | 2023-08-24

    There is Papermill ...

  • SynapseML

    Simple and Distributed Machine Learning

    Project mention: FLaNK Stack Weekly for 12 September 2023 | | 2023-09-12
  • sbt

    sbt, the interactive build tool

    Project mention: Declarative Gradle is a cool thing I am afraid of: Maven strikes back | | 2023-11-11

    NOTE: I won’t mention SBT and Leiningen here because, with all due respect, they are niche build tools. I also won’t discuss Kobalt for the same reason (besides, it’s no longer actively maintained). Additionally, I won’t touch upon Bazel and Buck in this context, mainly because I’m not very familiar with them. If you have insights or comments about these tools, please feel free to share them in the comments 👇

  • Scalaz

    Principled Functional Programming in Scala

    Project mention: Going into year 2 of Software Development Foundation Degree, have a particular liking for OOP and SQL, any tips, info or pointers on where to go from there? | /r/cscareerquestions | 2023-05-29

    I'm sorry, but have you ever done functional programming for a real company, like in a functional programming language like Haskell, Scala, or F#? Have you ever used Scala cats or scalaz? Have you ever learned category theory and how to apply its abstractions in software? Listen u/judethedude2106 this person hasn't gone as far down the functional programming rabbit hole as I have. Beyond learning the basics like the difference between pure and impure functions, what are closures, what higher order functions are and the most common ones like .map, .filter, and .flatmap, the immutable collections like immutable linked lists and trees, and what a Monad is and common monads like those used for futures/promises, async programming, and Option (Some or None, which is used instead of null checking), the more advanced functional programming stuff like category theory based abstractions are totally useless for real jobs and is just a giant time suck. Don't waste years on functional programming, spend at most a few months on it and no more.

  • BigDL

    Accelerate LLM with low-bit (FP4 / INT4 / FP8 / INT8) optimizations using bigdl-llm

    Project mention: BigDL-LLM: running LLM on your laptop using INT4 | | 2023-07-03
  • lsp-mode

    Emacs client/library for the Language Server Protocol

    Project mention: lsp-mode: Emacs client/library for the Language Server Protocol | /r/planetemacs | 2023-10-15
  • SaaSHub

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

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). The latest post mention was on 2023-11-11.

Scala related posts


What are some of the best open-source Scala projects? This list will help you:

Project Stars
1 Apache Spark 37,245
2 Apache Kafka 26,267
3 Apache Flink 22,288
4 scala 14,206
5 lila 13,999
6 Deeplearning4j 13,238
7 Play 12,461
8 kafka-manager 11,566
9 milewski-ctfp-pdf 10,489
10 mal 9,609
11 awesomo 9,095
12 Gitbucket 8,986
13 awesome-scala 8,859
14 Finagle 8,711
15 Zeppelin 6,195
16 Gatling 6,118
17 dotty 5,468
18 papermill 5,443
19 SynapseML 4,867
20 sbt 4,721
21 Scalaz 4,634
22 BigDL 4,550
23 lsp-mode 4,538
SaaSHub - Software Alternatives and Reviews
SaaSHub helps you find the best software and product alternatives