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Top 23 Scala Scala Projects
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Project mention: Introducing RisingWave's Hosted Iceberg Catalog-No External Setup Needed | dev.to | 2025-07-04
Because the hosted catalog is a standard JDBC catalog, tools like Spark, Trino, and Flink can still access your tables. For example:
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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.
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Project mention: Show HN: A Implementation of Alpha Zero for Chess in MLX | news.ycombinator.com | 2025-05-29
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scala
Scala 2 compiler and standard library. Scala 2 bugs at https://github.com/scala/bug; Scala 3 at https://github.com/scala/scala3
I’ve been a web developer for years, but I haven’t touched Java in a long time — like, late-90s long. Back then, Java development felt cumbersome: lots of boilerplate and complex configurations. It was not exactly a pleasant experience for building simple web apps. So when I recently started exploring Scala and the Play Framework, I was curious more than anything. Has the Java developer experience gotten better? Is it actually something I’d want to use today?
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~/project$ sbt run [info] welcome to sbt 1.10.6 (Ubuntu Java 17.0.14) [info] loading settings for project scala-api-heroku-build from plugins.sbt... [info] loading project definition from /home/alvin/repositories/devspotlight/heroku/scala/scala-api-heroku/project [info] loading settings for project root from build.sbt... [info] loading settings for project docs from build.sbt... [info] __ __ [info] \ \ ____ / /____ _ __ __ [info] \ \ / __ \ / // __ `// / / / [info] / / / /_/ // // /_/ // /_/ / [info] /_/ / .___//_/ \__,_/ \__, / [info] /_/ /____/ [info] [info] Version 3.0.6 running Java 17.0.14 [info] [info] Play is run entirely by the community. Please consider contributing and/or donating: [info] https://www.playframework.com/sponsors [info] --- (Running the application, auto-reloading is enabled) --- INFO p.c.s.PekkoHttpServer - Listening for HTTP on /[0:0:0:0:0:0:0:0]:9000 (Server started, use Enter to stop and go back to the console...)
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Gitbucket
A Git platform powered by Scala with easy installation, high extensibility & GitHub API compatibility
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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.
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Project mention: DevOps What is DevSecOps? A guide to secure software development | dev.to | 2025-06-09
Source control and collaboration: Git, GitHub, GitLab
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> 1) The language is too unstable
Thankfully not anymore. They got their act together and have been maintaining compatibility since Scala 3.0.0 has been released in May 2021, which is almost 4 years and counting.
https://github.com/scala/scala3/releases/tag/3.0.0
Scala 3.x is to remain compatible for the whole 3.x series (think of semantic versioning). There's no Scala 4 (breaking with Scala 3) in sight.
Also, Scala 3 and Scala 2.13 JARs are also compatible with each other, which helped with the transition.
> 2) The tooling around it is not the best
sbt may not be good. But Mill is much better than either Maven or Gradle. Especially Gradle. Bleep is also promising.
Scalafmt is widely used and liked. Scalafix -- the linter/fixer -- is used a bit less, but still of a good quality.
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> to see how they ended up in that situation
The "how" is almost always lack of discipline (or as I sometimes couch it, "imagination") but usually shit like https://github.com/microsoft/SynapseML/issues/405#:~:text=cl...
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Project mention: Zod: TypeScript-first schema validation with static type inference | news.ycombinator.com | 2024-10-07
You just gave me a flashback to scalaz https://github.com/scalaz/scalaz
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> Clojurescript for frontend, Rust for portability
If Clojure and Rust work well for you, more power to you. But at least in theory, you could very well use just Scala for these purposes
Scala can compile to JS https://www.scala-js.org/ if you target frontend.
And if you want portability, you can compile a Scala program with GraalVM's native-image and statically link everything with musl libc https://www.graalvm.org/latest/reference-manual/native-image...
And if you want both frontend and portability everywhere, Scala will soon have a support for compiling to WASM (with WASI, etc) https://github.com/scala-wasm/scala-wasm/ (to be integrated into Scala.js after developed)
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Project mention: Pipelining might be my favorite programming language feature | news.ycombinator.com | 2025-04-21
a) Scala with no JVM exists: https://scala-native.org
b) Async works on Scala Native: https://github.com/lampepfl/gears
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Project mention: Spade – A work in progress HDL that doesn't make you want to pull your hair out | news.ycombinator.com | 2025-03-25
How does this compare and contrast to other attempts at succeeding Verilog and VHDL, such as Chisel¹?
1: https://www.chisel-lang.org/
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I use ZIO (https://zio.dev) and nothing really like it exists on any platform.
You can wrap any computation in a single ZIO object e.g. normal, callback, future, promise etc. Which you can then chain together in different ways e.g. run them in parallel, sequentially, race them against each other and kill the loser, scheduling in elaborate ways etc.
And it will execute this either using normal or virtual threads i.e. fibers without locks so it’s extremely fast.
But the incredible part is that it does all of this whilst seamlessly handling every type of error. Which if you’ve ever written complex concurrent code is extremely hard to get right.
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TheHive: Facilitates collaborative incident response. TheHive
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deequ
Deequ is a library built on top of Apache Spark for defining "unit tests for data", which measure data quality in large datasets.
Deequ GitHub Repository
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> Combined with the extremely powerful compile-time reflection capabilities of D it's the closest thing I've seen to Lisp metaprogramming outside of that family of languages ...
Scala gets pretty close to LISP-level of metaprogramming support between its intrinsic support for macros[0] (not to be confused with the C/C++ preprocessor of the same name) the Scalameta project[1], and libraries such as Shapeless[2].
Not comparing Scala to D, just identifying a language with similar functionality.
0 - https://docs.scala-lang.org/scala3/reference/metaprogramming...
1 - https://scalameta.org/
2 - https://github.com/milessabin/shapeless
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elasticmq
In-memory message queue with an Amazon SQS-compatible interface. Runs stand-alone or embedded.
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Slick
Slick (Scala Language Integrated Connection Kit) is a modern database query and access library for Scala (by slick)
Project mention: Show HN: Node.js ORM to query SQL database through an array-like API | news.ycombinator.com | 2024-09-05Scala has a library called Slick which takes a similar approach: https://scala-slick.org
The DSL is nice for simple querying and for composing queries based upon user input. But, for anything slightly complex, I found it's better to just use regular SQL.
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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).
Scala Scala discussion
Scala Scala related posts
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DevOps What is DevSecOps? A guide to secure software development
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Chimney alternatives - ducktape and MapStruct
3 projects | 3 Jun 2025 -
Load testing vs performance testing
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Show HN: A Implementation of Alpha Zero for Chess in MLX
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API-First Development in Scala
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Pipelining might be my favorite programming language feature
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How to Reduce Big Data Analytics Costs by 90% with Karpenter and Spark
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A note from our sponsor - Stream
getstream.io | 13 Jul 2025
Index
What are some of the best open-source Scala projects in Scala? This list will help you:
| # | Project | Stars |
|---|---|---|
| 1 | Apache Spark | 41,441 |
| 2 | lila | 16,845 |
| 3 | scala | 14,388 |
| 4 | Play | 12,578 |
| 5 | kafka-manager | 11,894 |
| 6 | Gitbucket | 9,268 |
| 7 | Finagle | 8,829 |
| 8 | Gatling | 6,718 |
| 9 | dotty | 6,062 |
| 10 | SynapseML | 5,146 |
| 11 | sbt | 4,851 |
| 12 | Scalaz | 4,670 |
| 13 | Scala.js | 4,649 |
| 14 | Scala Native | 4,587 |
| 15 | chisel | 4,322 |
| 16 | ZIO | 4,229 |
| 17 | TheHive | 3,673 |
| 18 | rocket-chip | 3,492 |
| 19 | deequ | 3,460 |
| 20 | Shapeless | 3,399 |
| 21 | Twitter Util | 2,716 |
| 22 | elasticmq | 2,689 |
| 23 | Slick | 2,662 |
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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