frontpage.
newsnewestaskshowjobs

Made with ♥ by @iamnishanth

Open Source @Github

fp.

Open in hackernews

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

https://github.com/moustafa-nasr/fahmatrix
46•mousomashakel•10mo 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•10mo 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•10mo 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•10mo 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•10mo 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•10mo ago
Polars and duckdb interoperate nicely and can enable this flexibility
theanonymousone•10mo ago
Does Polars have a Java library?
mousomashakel•10mo 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.
theanonymousone•10mo 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•10mo 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.
skanga•10mo ago
What about Tablesaw, Apache Arrow? How does this compare ...
mousomashakel•10mo 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•10mo ago
Nice!

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

mousomashakel•10mo 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.

Show HN: An interactive map of Tolkien's Middle-earth

https://middle-earth-interactive-map.web.app/
111•frasermarlow•6h ago•22 comments

Show HN: Brutalist Concrete Laptop Stand (2024)

https://sam-burns.com/posts/concrete-laptop-stand/
712•sam-bee•16h ago•218 comments

Show HN: Gemma 4 Multimodal Fine-Tuner for Apple Silicon

https://github.com/mattmireles/gemma-tuner-multimodal
132•MediaSquirrel•7h ago•20 comments

Show HN: Unicode Steganography

https://steganography.patrickvuscan.com
21•PatrickVuscan•14h ago•3 comments

Show HN: A cartographer's attempt to realistically map Tolkien's world

https://www.intofarlands.com/atlasofarda
153•intofarlands•15h ago•26 comments

Show HN: Pion/handoff – Move WebRTC out of browser and into Go

https://github.com/pion/handoff
93•Sean-Der•15h ago•17 comments

Show HN: Finalrun – Spec-driven testing using English and vision for mobile apps

https://github.com/final-run/finalrun-agent
23•ashish004•12h ago•10 comments

Show HN: Stop paying for Dropbox/Google Drive, use your own S3 bucket instead

https://locker.dev
228•Zm44•16h ago•190 comments

Show HN: Can an AI model fit on a single pixel?

https://github.com/dvelton/ai-pixel
3•deevelton•2h ago•1 comments

Show HN: Kerf-CLI – SQLite-backed cost analytics for Claude Code

https://github.com/dhanushkumarsivaji/kerf-cli
6•dhanushkumars•3h ago•0 comments

Show HN: Mo – checks GitHub PRs against decisions approved in Slack

https://motionode.com/index
3•oscarcaldera•5h ago•0 comments

Show HN: Ghost Pepper – Local hold-to-talk speech-to-text for macOS

https://github.com/matthartman/ghost-pepper
453•MattHart88•1d ago•194 comments

Show HN: Anos – a hand-written ~100KiB microkernel for x86-64 and RISC-V

https://github.com/roscopeco/anos
107•noone_youknow•3d ago•31 comments

Show HN: Hippo, biologically inspired memory for AI agents

https://github.com/kitfunso/hippo-memory
120•kitfunso•1d ago•23 comments

Show HN: Tusk for macOS and Gnome

https://shapemachine.xyz/tusk/
114•factorialboy•3d ago•42 comments

Show HN: AdaShape-3D modeler for intuitive 3D printing parts / Windows 11

https://adashape.com
31•fsloth•3d ago•27 comments

Show HN: I built a tiny LLM to demystify how language models work

https://github.com/arman-bd/guppylm
892•armanified•2d ago•134 comments

Show HN: Open-source GDPR router for LLMs detects PII, forces EU-only inference

https://github.com/mahadillahm4di-cyber/mh-gdpr-ai.eu
4•mahadillah-ai•5h ago•0 comments

Show HN: GovAuctions lets you browse government auctions at once

https://www.govauctions.app/
312•player_piano•1d ago•88 comments

Show HN: TTF-DOOM – A raycaster running inside TrueType font hinting

https://github.com/4RH1T3CT0R7/ttf-doom
63•4RH1T3CT0R•1d ago•12 comments

Show HN: A (marginally) useful x86-64 ELF executable in 298 bytes

https://github.com/meribold/btry
10•meribold•11h ago•0 comments

Show HN: Real-time AI (audio/video in, voice out) on an M3 Pro with Gemma E2B

https://github.com/fikrikarim/parlor
285•karimf•2d ago•35 comments

Show HN: Gemma Gem – AI model embedded in a browser – no API keys, no cloud

https://github.com/kessler/gemma-gem
153•ikessler•2d ago•20 comments

Show HN: A social feed with no algo where communities decide what gets seen

https://veridonia.com
6•smnkgv•14h ago•5 comments

Show HN: A game where you build a GPU

https://jaso1024.com/mvidia/
954•Jaso1024•3d ago•186 comments

Show HN: I made a YouTube search form with advanced filters

https://playlists.at/youtube/search/
318•nevernothing•2d ago•201 comments

Show HN: Weird Clocks

https://clocks.specr.net
48•vunderba•1d ago•16 comments

Show HN: The King James Bible deserved a better website

https://officialkingjamesbible.com/
7•L23234•13h ago•3 comments

Show HN: Modo – I built an open-source alternative to Kiro, Cursor, and Windsurf

https://github.com/mohshomis/modo
98•mohshomis•2d ago•26 comments

Show HN: Marimo pair – Reactive Python notebooks as environments for agents

https://github.com/marimo-team/marimo-pair
24•manzt•9h ago•1 comments