Skip to content
OpenSrc
The directory

Language

Scala repos to contribute to

OpenSrc lists 27 Scala repositories with open issues for new contributors, and 14 of them are first-PR friendly. Between them they have 366 open good first issues and 369 help-wanted issues. The median welcome score is 74/100, and the best-scored right now are lichess-org/lila, playframework/playframework and NVIDIA/cudf-spark. Most are about DevOps & Cloud, Backend & APIs and Databases.

27 repos by best score

Filter these in the directory

  • lichess-org/lila

    ♞ lichess.org: the forever free, adless and open source chess server ♞

    5good first issues
    • Scala
    • Field: Game Dev
    • Stars:18.8K
    • AGPL-3.0
    • CONTRIBUTING
    • replies in ~9h
    Score86 out of 100 contributor score, very welcomingFirst-PR friendly

  • playframework/playframework

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

    26good first issues+68 help wanted
    • Scala
    • Field: Web Frontend
    • Stars:12.6K
    • Apache-2.0
    • CONTRIBUTING
    • replies in ~15d
    Score85 out of 100 contributor score, very welcoming

  • NVIDIA/cudf-spark

    NVIDIA cuDF for Apache Spark plugin - accelerate Apache Spark with GPUs

    43good first issues
    • Scala
    • Field: Graphics
    • Stars:1K
    • CONTRIBUTING
    Score84 out of 100 contributor score, very welcomingFirst-PR friendly

  • http4s/http4s

    A minimal, idiomatic Scala interface for HTTP

    14good first issues
    • Scala
    • Field: Networking
    • Stars:2.6K
    • Apache-2.0
    • CONTRIBUTING
    Score81 out of 100 contributor score, very welcomingFirst-PR friendly

  • VirtusLab/scala-cli

    Scala CLI is a command-line tool to interact with the Scala language. It lets you compile, run, test, and…

    12good first issues
    • Scala
    • Field: CLI Tools
    • Stars:644
    • Apache-2.0
    • CONTRIBUTING
    • replies in ~4d
    Score81 out of 100 contributor score, very welcoming

  • scalaz/scalaz

    Principled Functional Programming in Scala

    16good first issues
    • Scala
    • Stars:4.7K
    • CONTRIBUTING
    Score80 out of 100 contributor score, very welcomingFirst-PR friendly

  • apache/openwhisk

    Apache OpenWhisk is an open source serverless cloud platform

    19good first issues+28 help wanted
    • Scala
    • Field: DevOps
    • Stars:6.8K
    • Apache-2.0
    • CONTRIBUTING
    Score78 out of 100 contributor score, very welcomingFirst-PR friendly

  • chipsalliance/chisel

    Chisel: A Modern Hardware Design Language

    6good first issues+1 help wanted
    • Scala
    • Field: Embedded
    • Stars:4.8K
    • Apache-2.0
    • CONTRIBUTING
    Score78 out of 100 contributor score, very welcomingFirst-PR friendly

  • llm4s/llm4s

    Agentic and LLM Programming in Scala

    15good first issues+4 help wanted
    • Scala
    • Field: Machine Learning
    • Stars:266
    • MIT
    • CONTRIBUTING
    Score78 out of 100 contributor score, very welcomingFirst-PR friendly

  • spotify/scio

    A Scala API for Apache Beam and Google Cloud Dataflow.

    10good first issues
    • Scala
    • Field: DevOps
    • Field: Machine Learning
    • Stars:2.6K
    • Apache-2.0
    • CONTRIBUTING
    Score77 out of 100 contributor score, very welcomingFirst-PR friendly

  • scalikejdbc/scalikejdbc

    A tidy SQL-based DB access library for Scala developers. This library naturally wraps JDBC APIs and provides…

    15good first issues
    • Scala
    • Field: Databases
    • Field: Backend
    • Stars:1.3K
    • Apache-2.0
    • CONTRIBUTING
    Score75 out of 100 contributor score, very welcomingFirst-PR friendly

  • apache/kyuubi

    Apache Kyuubi is a distributed and multi-tenant gateway to provide serverless SQL on data warehouses and…

    12good first issues+27 help wanted
    • Scala
    • Field: Databases
    • Field: DevOps
    • Stars:2.4K
    • Apache-2.0
    • CONTRIBUTING
    • replies in ~30d
    Score74 out of 100 contributor score, welcoming

  • apache/gluten

    Gluten is a middle layer responsible for offloading JVM-based SQL engines' execution to native engines.

    15good first issues
    • Scala
    • Field: Databases
    • Stars:1.6K
    • Apache-2.0
    • CONTRIBUTING
    Score74 out of 100 contributor score, welcomingFirst-PR friendly

  • zio/zio-config

    Easily use and document any config from anywhere in ZIO apps

    11good first issues
    • Scala
    • Stars:244
    • Apache-2.0
    • CONTRIBUTING
    Score74 out of 100 contributor score, welcomingFirst-PR friendly

  • typelevel/cats-effect

    The pure asynchronous runtime for Scala

    7good first issues
    • Scala
    • Stars:2.2K
    • Apache-2.0
    • CONTRIBUTING
    • replies in ~6d
    Score73 out of 100 contributor score, welcoming

  • scala/scala3

    The Scala 3 compiler, also known as Dotty.

    3good first issues+16 help wanted
    • Scala
    • Field: Compilers
    • Stars:6.3K
    • Apache-2.0
    • CONTRIBUTING
    • replies in ~5h
    Score72 out of 100 contributor score, welcomingFirst-PR friendly

  • firesim/firesim

    FireSim: Fast and Effortless FPGA-accelerated Hardware Simulation with On-Prem and Cloud Flexibility

    17good first issues+1 help wanted
    • Scala
    • Field: DevOps
    • Field: Embedded
    • Stars:1K
    • CONTRIBUTING
    Score72 out of 100 contributor score, welcomingFirst-PR friendly

  • akka/akka-core

    A platform to build and run apps that are elastic, agile, and resilient. SDK, libraries, and hosted…

    4good first issues+200 help wanted
    • Scala
    • Field: DevOps
    • Field: OS
    • Stars:13.3K
    • CONTRIBUTING
    • replies in ~30d
    Score70 out of 100 contributor score, welcoming

  • zio/zio

    ZIO — A type-safe, composable library for async and concurrent programming in Scala

    4good first issues+3 help wanted
    • Scala
    • Stars:4.4K
    • Apache-2.0
    • CONTRIBUTING
    • replies in ~30d
    Score69 out of 100 contributor score, welcoming

  • delta-io/delta

    An open-source storage framework that enables building a Lakehouse architecture with compute engines…

    11good first issues
    • Scala
    • Field: Data Science
    • Field: Backend
    • Stars:9K
    • Apache-2.0
    • CONTRIBUTING
    • replies in ~30d
    Score68 out of 100 contributor score, welcoming

  • bitcoin-s/bitcoin-s

    Bitcoin Implementation in Scala

    31good first issues
    • Scala
    • Field: Blockchain
    • Field: Networking
    • Stars:383
    • MIT
    • CONTRIBUTING
    • replies in ~30d
    Score68 out of 100 contributor score, welcoming

  • apache/datafusion-comet

    Apache DataFusion Comet Spark Accelerator

    8good first issues+1 help wanted
    • Scala
    • Stars:1.3K
    • Apache-2.0
    • CONTRIBUTING
    Score67 out of 100 contributor score, welcomingFirst-PR friendly

  • turtles, patches, and links for kids, teachers, and scientists

    5good first issues
    • Scala
    • Stars:1.2K
    • GPL-2.0
    • replies in ~1h
    Score67 out of 100 contributor score, welcoming

  • canton-network/splice

    Splice repository

    9good first issues+2 help wanted
    • Scala
    • Stars:118
    • Apache-2.0
    • CONTRIBUTING
    • replies in ~20d
    Score65 out of 100 contributor score, welcoming

  • reibitto/command-center

    A CLI-based launcher and general productivity tool.

    26good first issues+1 help wanted
    • Scala
    • Field: CLI Tools
    • Stars:109
    • Apache-2.0
    Score65 out of 100 contributor score, welcoming

  • scala-native/scala-native

    Your favorite language gets closer to bare metal.

    4good first issues
    • Scala
    • Field: Compilers
    • Stars:4.7K
    • replies in ~30d
    Score55 out of 100 contributor score, welcoming

  • 7mind/izumi

    Productivity-oriented collection of lightweight fancy stuff for Scala toolchain

    18good first issues+17 help wanted
    • Scala
    • Field: Observability
    • Stars:629
    • BSD-2-Clause
    Score43 out of 100 contributor score, some assembly required

Every Monday

Get a weekly patch

New Scala repos that joined the directory this week, with open good first issues and maintainers who reply. One email, no tracking, unsubscribe in one click.

Follow new repos by RSS