frontpage.
newsnewestaskshowjobs

Open Source @Github

fp.

Show HN: Aldine. Self-hosted Overleaf alternative. Every paper = 1 Git Repo

https://github.com/trahloff/Aldine
2•rahloff•40m ago•1 comments

Show HN: Reladraw – A diagram language where you decide where to place things

https://github.com/reladraw/reladraw
333•jpwalsh234•19h ago•90 comments

Show HN: An OpenAI-compatible, model-agnostic agent API

https://rebyte.ai/docs/agents-api/overview
2•sonicgg•1h ago•0 comments

Show HN: LightCloud – A cloud console organised like file system

https://www.light-cloud.com/
6•yullius•2h ago•2 comments

Show HN: Peekaboolean – image and jev-like typed questions in typed anwers out

https://github.com/bykof/peekaboolean
2•bykof•2h ago•0 comments

Show HN: Afterlife Vault – a virtual dead man's switch

https://afterlife-vault.com
2•wmeter•2h ago•2 comments

Show HN: Jev Plays Pokémon Red

https://jev-pokemon.vercel.app/
263•pancomplex•1d ago•115 comments

Show HN: I built an AR App that overlays makeup tutorials live on your face

https://urartist.app/
3•Vicmed13•3h ago•3 comments

Show HN: Ekselio – Loveable for finance workflows (local first)

https://www.gptbeyond.com/try?home=1
34•kdautaj•1d ago•10 comments

Show HN: An interactive debugger for the Mornington Crescent esolang

https://codeberg.org/Two9A/mcresc
3•Two9A•4h ago•0 comments

Show HN: Ppgrid – Rasterising points in minutes, not hours

https://mrzk.io/posts/ppgrid-fast-continentscale-raster-interpolation/
2•marzukia•5h ago•0 comments

Show HN: Trail – new kind of logic game

https://trail.franzai.com/
5•franze•5h ago•1 comments

Show HN: Shipwithmuse.live – a catalog of things people built with Muse

https://shipwithmuse.live/
4•mdayan896•7h ago•2 comments

Show HN: Hacker Atlas - A map of what Hacker News talks about

https://hackeratlas.com/
84•andrearitossa•1d ago•26 comments

Show HN: Spivak's Calculus formalized in Lean 4 – every theorem, every problem

https://github.com/stormj-UH/spivak-lean
17•jsLavaGoat•19h ago•2 comments

Show HN: A Claude Code skill to analyze your chess games

https://github.com/brumar/chess-postmortem-skills
73•brumar•21h ago•53 comments

Show HN: Whiteboard (YC W26) – An open-source IDE for thoughtful software design

https://github.com/devdotfast/whiteboard
412•sidharthkmenon•2d ago•141 comments

Show HN: I checked 1M free proxies – 1 in 5 working ones injected scripts

https://github.com/maximilianfeix/proxy-scraper
10•taventix•22h ago•1 comments

Show HN: Air-gapped file encryption as self-decrypting HTML page

https://cms-sfx-demo.apeleg.com/
89•emurlin•3d ago•30 comments

Show HN: AgentRun: DSL to turn agents into workflows

https://github.com/Parcha-ai/agentrun
50•miguelrios•3d ago•12 comments

Show HN: Koi.rest – watch some fish and regain your balance

https://koi.rest
224•hxii•2d ago•62 comments

Show HN: Treepeat – Code similarity detection using Tree-sitter

https://github.com/dsummersl/treepeat
71•91awebsi•4d ago•8 comments

Show HN: Make cursed fonts like Times New Bastard

https://bastardica.mitpit.com
854•MitPitt•3d ago•123 comments

Show HN: CaughtShipping – curfew app for developers, enforced by a public wall

https://caughtshipping.com/
4•misulicus•17h ago•0 comments

Show HN: Sixb, a TypeScript ontology framework for modeling your domain

https://docs.sixb.ai
2•ademattos•18h ago•1 comments

Show HN: Jevgpt – reinventing the wheel with another wheel

25•kunggaochicken•3d ago•2 comments

Show HN: Agentic CUDA Kernel Optimizer

https://github.com/bertaye/agentic-cuda-optimizer
37•bertaye•2d ago•11 comments

Show HN: Cocytus – an esolang where freezes after N accesses

https://github.com/fireside25a-beep/Cocytus
3•natgrish•18h ago•0 comments

Show HN: Drop – A rootless Linux sandbox with gVisor support

https://droprun.sh/
192•mixedbit•4d ago•63 comments

Show HN: Recurse – Develop and deploy specialist agents faster

https://recurse.run
8•ozankabak•1d ago•4 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.