frontpage.
newsnewestaskshowjobs

Open Source @Github

fp.

Show HN: Hack Club Folktale: Learn Python, Make a Game, Get Free Stickers

https://folktale.hackclub.com/
2•breynard•52m ago•1 comments

Show HN: A new way to read books, magnifying in and out

https://book.curiora.space/
3•pentagram•1h ago•0 comments

Show HN: Frugal Tokens – explore costs and usage across coding agents

https://demo.frugaltokens.com/
26•dpc94•6h ago•6 comments

Show HN: Turning websites into micro CLIs for Claude Code to save on tokens

https://github.com/only-cli/oc
3•hyes•2h ago•2 comments

Show HN: Automatically detect and patch walking-dead states in Sierra games

https://github.com/katiahayati/lucasartsifier/
139•wkfauna•21h ago•83 comments

Show HN: Nikon F100 Film Camera Repair Notes

https://github.com/enthdegree/f100
41•enthdegree•4d ago•20 comments

Show HN: HyperSAE – Sparse Autoencoders, reimagined in hyperbolic space

https://github.com/vishal-dehurdle/hypersae
3•visha1v•3h ago•0 comments

Show HN: Interactive, animated architecture of any HuggingFace models

https://modelmap.cc
106•lizhaoliu•23h ago•11 comments

Show HN: terminal-code – VS Code inside the terminal

https://terminal-code.com
3•robpruzan•6h ago•1 comments

Show HN: Invoicing and Tax for UK Tradespeople

https://tradetally.co.uk
3•wowinter15•4h ago•0 comments

Show HN: Anonymous age verification with passkey-powered encryption

https://loginwithone.com/
10•mikeysight•9h ago•5 comments

Show HN: Openleetcode – Local LeetCode runner where tests live in the repo

https://github.com/therepanic/openleetcode
70•therepanic•1d ago•18 comments

Show HN: Saggar, a Mac terminal that keeps sessions and your attention organized

https://saggar.marginalutility.dev/
66•mcclowes•2d ago•59 comments

Show HN: HRAG – Hybrid RAG on €116/month of Hetzner, officially benchmarked

https://hrag.app/
5•victor_edka•5h ago•0 comments

Show HN: Naeos – an engineering system for AI coding agents

https://github.com/NAEOS-foundation/naeos
3•bayu911•6h ago•0 comments

Show HN: nanoAlphaZero – Train a grandmaster-level chess model in 24h with TPUs

https://github.com/wtedw/nanoAlphaZero
2•tdoubleu•7h ago•0 comments

Show HN: I am getting genuine questions

https://github.com/docbrain-ai/docbrain
2•bhanuhai2•7h ago•3 comments

Show HN: LongTerMemory, an AI EdTech Platform

https://wired.business/longtermemory
2•aledevv•7h ago•0 comments

Show HN: a javascript engine written in C3 with native TS support

https://github.com/ricardobeat/boomkat
3•ricardobeat•8h ago•1 comments

Show HN: Desktopcolors.com – A museum for solid background colors of classic OS

https://desktopcolors.com
165•vlowrian•2d ago•71 comments

Show HN: macOS data protection keychain for Electron apps

https://github.com/biw/keychain-store
24•biwills•1d ago•3 comments

Show HN: Progressive web-app to explore Paris while solving puzzles without app

https://flanori.com/
6•rhazn•9h ago•0 comments

Show HN: Verify OpenAI's signed agent traffic in Python (RFC 9421/Web Bot Auth)

https://github.com/regent-protocol/regent-httpsig
3•abay_aubakirov•9h ago•0 comments

Show HN: Xalgorix – open-source AI pentester that proves vulnerabilities

https://www.xalgorix.com/
6•xalgord•9h ago•4 comments

Show HN: My Mac slept through its cron jobs, so I made goguma, a menu bar app

https://github.com/junnam586/goguma
5•junnam586•9h ago•2 comments

Show HN: Marginal – See which customers and features drive your AI API costs

https://marginalhq.com/
4•jithinlalk25•10h ago•0 comments

Show HN: Shoehorn – Quantize any model down to run on your machine

https://notactuallytreyanastasio.github.io/shoehorn/
45•rhgraysonii•1d ago•9 comments

Show HN: Carno.js – a Nest-style application framework for Bun

https://github.com/carnojs/carno.js
6•l-crispr•10h ago•1 comments

Show HN: LLM-Shield-Proxy Zero-Egress PII Streaming Proxy (55MB RAM)

https://github.com/ninadphalak/LLM-Shield-Proxy
4•ninadphalak•11h ago•1 comments

Show HN: Sokoban AI Solver

https://mkornreich.me/projects/sokoban/
71•enjoyyourlife•2d ago•42 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.