frontpage.
newsnewestaskshowjobs

Made with ♥ by @iamnishanth

Open Source @Github

fp.

Show HN: Rocket Launch and Orbit Simulator

https://www.donutthejedi.com/
102•donutthejedi•8h ago•30 comments

Show HN: Scroll Wikipedia like TikTok

https://quack.sdan.io
178•sdan•9h ago•47 comments

Show HN: Miditui – a terminal app/UI for MIDI composing, mixing, and playback

https://github.com/minimaxir/miditui
7•minimaxir•1d ago•0 comments

Show HN: Yellopages – New tab Chrome extension

https://yellopages.kawaicheung.io/
9•kiwigod17•1d ago•1 comments

Show HN: I made a memory game to teach you to play piano by ear

https://lend-me-your-ears.specr.net
424•vunderba•10h ago•153 comments

Show HN: A website that auctions itself daily

https://www.thedailyauction.com/
24•nsomani•1d ago•7 comments

Show HN: Similarity = cosine(your_GitHub_stars, Karpathy) Client-side

https://puzer.github.io/github_recommender/
123•puzer•3d ago•34 comments

Show HN: EuConform – Offline-first EU AI Act compliance tool (open source)

https://github.com/Hiepler/EuConform
57•hiepler•8h ago•34 comments

Show HN: Various shape regularization algorithms

https://github.com/nickponline/shreg
49•nickponline•1d ago•4 comments

Show HN: Roleplay-first chat UI for an OpenAI-compatible chat completions API

https://abliteration.ai/roleplay
3•abliterationai•1d ago•1 comments

Show HN: Repogen – a static site generator for package repositories

https://github.com/ralt/repogen
21•tlar•3d ago•3 comments

Show HN: Turn any topic into a 3Blue1Brown-style video

https://github.com/mateolafalce/topic2manim
2•lafalce•1h ago•0 comments

Show HN : A game to document my electronics learning journey.

https://jeevan.life/theapplefalls/
21•ssunboyy•6d ago•8 comments

Show HN: Executable Markdown files with Unix pipes

112•jedwhite•1d ago•92 comments

Show HN: I vibecoded an ARM64 operating system that boots on real hardware

https://github.com/kaansenol5/VibeOS
6•kaansenol5•3h ago•0 comments

Show HN: I built a tool to create AI agents that live in iMessage

https://tryflux.ai/
50•danielsdk•5d ago•23 comments

Show HN: macOS menu bar app to track Claude usage in real time

https://github.com/richhickson/claudecodeusage
152•RichHickson•1d ago•48 comments

Show HN: I built an app that blocks social media until you read Quran daily

4•kalyfacloud•5h ago•0 comments

Show HN: ElixirBrowser – Android Chromium fork with extensions, inspired by Kiwi

https://github.com/SF-FLAM/ElixirBrowser
9•SF-FLAM•10h ago•0 comments

Show HN: Immich AutoTag – A Python tool for automatic classification via API

https://github.com/txemi/immich-autotag
4•txemitron•7h ago•0 comments

Show HN: Accio – Summon apps with keyboard shortcuts

https://github.com/bjornorri/Accio
3•bjornorri•7h ago•0 comments

Show HN: DeepDream for Video with Temporal Consistency

https://github.com/jeremicna/deepdream-video-pytorch
69•fruitbarrel•1d ago•25 comments

Show HN: I visualized the entire history of Citi Bike in the browser

https://bikemap.nyc/
109•freemanjiang•2d ago•31 comments

Show HN: Ever wanted to look at yourself in Braille?

https://github.com/NishantJoshi00/dith
10•cat-whisperer•19h ago•0 comments

Show HN: A geofence-based social network app 6 years in development

https://www.localvideoapp.com
74•Adrian-ChatLocl•1d ago•57 comments

Show HN: Commit-based code review instead of PR-based

https://commitguard.ai
14•moshetanzer•21h ago•2 comments

Show HN: Agent-contracts, contract-based LangGraph agents

https://github.com/yatarousan0227/agent-contracts
7•yatarousan•10h ago•0 comments

Show HN: GitChoco – virtual Chocolatey for GitHub Releases

https://gitcho.co/
4•lostmsu•10h ago•0 comments

Show HN: I built a "Do not disturb" Device for my home office

https://apoorv.page/blogs/over-engineered-dnd
96•quacky_batak•6d ago•49 comments

Show HN: CLIs Are All You Need for Agents

https://github.com/caesarnine/binsmith
3•binalpatel•11h ago•0 comments
Open in hackernews

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

https://github.com/moustafa-nasr/fahmatrix
46•mousomashakel•7mo 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•7mo 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•7mo 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•7mo 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•7mo 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•7mo ago
Polars and duckdb interoperate nicely and can enable this flexibility
theanonymousone•7mo ago
Does Polars have a Java library?
mousomashakel•7mo 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•7mo 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•7mo 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•7mo ago
What about Tablesaw, Apache Arrow? How does this compare ...
mousomashakel•7mo 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•7mo ago
Nice!

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

mousomashakel•7mo 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.