frontpage.
newsnewestaskshowjobs

Open Source @Github

fp.

Show HN: To Honor Sir Patrick Stewart, Enjoy the TNG Episode Guessing Game

https://tng.episodle.com/
8•francisofascii•19m ago•2 comments

Show HN: A working Nintendo in ~1GB of Qwen weights

https://github.com/dbreunig/nesformer
175•dbreunig•7h ago•108 comments

Show HN: Sketch Stadium – watch your agent play Pictionary

https://sketch.wakeshift.ai/games/q5ucru
19•ericlevine•8h ago•7 comments

Show HN: I built a multiplayer game where you're an aerial fighter cat

https://catcopter.com
77•pawelwentpawel•8h ago•38 comments

Show HN: Spinf-serve – inference server for bulk scoring and decisions

https://github.com/spinfinc/spinf-serve
18•giarec•7h ago•3 comments

Show HN: Balk – A Baseball Game

https://balk.club
3•mandymoorefan•2h ago•0 comments

Show HN: News article bias detector tool

https://aethelgard.news/
2•Tryvrsakjo10•2h ago•0 comments

Show HN: Optimized CUDA forced alignment kernels. 10x – 1000x faster

https://github.com/brthor/fast-forced-aligner
3•bthornbury•3h ago•0 comments

Show HN: I Turned DOOM into a Transformer

https://github.com/mottopanikeiku/doomformer
123•falperc•1d ago•36 comments

Show HN: HackerFlow – A Responsive HN Reader

https://hn.vinceroyer.ca/
2•vinistois•3h ago•0 comments

Show HN: Fraktur, a DJ mixing app in the browser

https://greenvitriol.com/posts/fraktur
17•janesconference•10h ago•0 comments

Show HN: Slotwatch – watch Postgres replication slots from the terminal

https://github.com/Dem1241/slotwatch
2•ish1907•3h ago•0 comments

Show HN: Auto Dismiss Mac OS "Allow <app> to find devices on local networks?"

https://github.com/johncassil/dontallow
149•johncassil•1d ago•124 comments

Show HN: Cerebellum – small model on the robot, big model for what it can't undo

https://github.com/cerebellum-labs/cerebellum
3•dminglv•4h ago•1 comments

Show HN: Rust based window switcher for macOS

https://alt-tabr.com/
4•nima999•4h ago•0 comments

Show HN: PicoPlayer – A tiny, open-source website for playing quality webgames

https://picoplayer.net/
8•popcar2•10h ago•7 comments

Show HN: Fishoid: an ambient fish tank for your screen

https://fishoid.net/
4•koskokos•5h ago•4 comments

Show HN: A proof-of-concept formalization of the IRS federal tax forms

https://github.com/emmilco/us-tax-model
80•RGS1811•2d ago•12 comments

Show HN: Lasm – Write formally verified webapps in Lean for Node/serverless/edge

https://github.com/Millillion/lasm
35•lastmjs•22h ago•20 comments

Show HN: Magical Share - Share files with light

https://apps.zincirx.com/magicalshare/
2•zincirx•5h ago•1 comments

Show HN: Chess960v2 – Over 800 Rounds Played

https://chess960v2.com/en
2•lavren1974•6h ago•0 comments

Show HN: Deckdrill – Pimsleur-style audio drills from Anki decks, in your voice

https://www.deckdrill.app
2•pjacowski•6h ago•0 comments

Show HN: Hashsync – Deduplicate SSH streams against the receiver's files

https://github.com/someplaceguy/hashsync
2•someplaceguy•7h ago•0 comments

Show HN: Overtone – Transcribe, correct and cut captions for any screen shape

https://github.com/lonthq/overtone-captions
43•rvanderlinden•1d ago•8 comments

Show HN: Keyward – a TUI to manage SSH keys and audit your –/.ssh security

https://github.com/gateway-of-last-resort/keyward
2•weiqur•8h ago•0 comments

Show HN: Arken – Passwordless auth middleware using secp256k1 keys

https://github.com/zacharybenson/arken-protocol
12•zachbenson817•22h ago•0 comments

Show HN: Tinycap, a tiny Mac screen recorder that makes PR-sized GIFs and MP4s

https://soleo.github.io/tinycap/
4•soleo•9h ago•2 comments

Show HN: Every Permutation of a Deck of Cards

https://mrrc.cc/52!/
2•mrrccc•10h ago•1 comments

Show HN: Showbuild – Hacker News but only for builders

https://showbuild.co/
5•ritik30•11h ago•1 comments

Show HN: SlideBySide – Present slides without sharing your screen

https://slidebyside.com/
81•denismenace•2d ago•35 comments
Open in hackernews

Show HN: Fahmatrix – A Lightweight, Pandas-Like DataFrame Library for Java

https://github.com/moustafa-nasr/fahmatrix
46•mousomashakel•1y ago
Hey HN, I’ve built Fahmatrix, a minimal, fast Java library for working with tabular data — inspired by Python’s pandas, but designed for performance and simplicity on the JVM.

After working extensively with Python’s data stack, I often ran into limitations related to speed, especially in larger or long-running data workflows. So I built Fahmatrix from scratch to offer similar APIs for manipulating CSVs, performing summary statistics, slicing rows/columns, and more — but all in Java.

Features:

Lightweight and dependency-free

CSV/TSV import with auto-headers

Series/DataFrame structures (like pandas)

describe(), mean(), stdDev(), percentile() and more

Fast parallel operations on numeric columns

Java 17+ support

Docs: https://moustafa-nasr.github.io/Fahmatrix/ GitHub: https://github.com/moustafa-nasr/fahmatrix

I’d love feedback from the Java and data communities — especially if you’ve ever wanted a simple dataframe utility in Java without needing full-scale ML libraries.

Happy to answer any questions!

Comments

rickette•1y ago
Congrats on putting this out there. There isn't a de facto pandas-like library in Java like you said. But for Kotlin there is: https://github.com/Kotlin/dataframe
mousomashakel•1y ago
Thanks so much! Yep, I’ve seen the Kotlin DataFrame lib — very elegant. Fahmatrix is meant for plain Java users who want similar capabilities without switching ecosystems. Appreciate the support!
uwemaurer•1y ago
Always great to see efforts to make working with data frames easier. Here are some similar data frame libraries for Java:

https://github.com/jtablesaw/tablesaw

https://github.com/dflib/dflib

My preferred way is just use duckdb java API. I didn't see anything better in performance/efficiency. Also a SQL query is often easier to write

theanonymousone•1y ago
Yes. It has bothered me for a long time too. Maybe the best mix is a dataframe library with basic operations (column select, non-null etc), which also allows SQL for more complex stuff?
radus•1y ago
Polars and duckdb interoperate nicely and can enable this flexibility
theanonymousone•1y ago
Does Polars have a Java library?
mousomashakel•1y ago
Totally agree that SQL can be the best tool for many jobs. My goal with Fahmatrix is to serve the opposite niche: where devs want something that's Java-native, procedural, and simple without reaching for an external engine. SQL support or DSL might come later though — I see the appeal.
skanga•1y ago
What about Tablesaw, Apache Arrow? How does this compare ...
mousomashakel•1y ago
Good question. I’ll publish benchmarks soon, but the core difference is that Fahmatrix is fully Java, no JNI, and minimalistic — ideal for small projects or environments like Android. Tablesaw and Arrow are more powerful, but heavier. Fahmatrix aims to be the “just enough” middle ground.
owlstuffing•1y ago
Nice!

I’m currently using manifold-sql with duckdb for this.

mousomashakel•1y ago
Thanks! That’s a great combo — manifold-sql + duckdb gives you strong typing with powerful SQL under the hood. Fahmatrix is aiming to complement that approach for cases where you want quick, native Java code without SQL — e.g., when building data flows or custom logic inline. Would love to hear if you’ve hit any pain points that a Java-native approach could help with.
theanonymousone
•
1y ago
Sure. So maybe notehr comment would be to make it (particularly the Series class), as compatible with Java Streams as possible.

Next step would likely be compatibility with popular libraries such as Apache Commons Math: https://commons.apache.org/proper/commons-math/userguide/sta...

mousomashakel•1y ago
Thanks! I'm aware of those great projects. Fahmatrix aims to offer a lightweight, dependency-free alternative that’s easy to embed in any Java app. DuckDB is super impressive, especially for SQL-heavy tasks — but my goal is more about a native, fluent API for those who prefer direct Java code over SQL.