frontpage.
newsnewestaskshowjobs

Made with ♥ by @iamnishanth

Open Source @Github

fp.

Show HN: DBOS Java – Postgres-Backed Durable Workflows

https://github.com/dbos-inc/dbos-transact-java
8•KraftyOne•56m ago•0 comments

Show HN: LLM fine-tuning without infra or ML expertise (early access)

https://www.tinytune.xyz/
3•Jacques2Marais•2h ago•1 comments

Show HN: What Can Happen When You Code While Overtired

https://number-garden-story.netlify.app/
3•cpuXguy•3h ago•0 comments

Show HN: AI Bubble Monitor

https://aibubblemonitor.com
19•itsnotmyai•12h ago•1 comments

Show HN: Gerbil – an open source desktop app for running LLMs locally

https://github.com/lone-cloud/gerbil
34•lone-cloud•2d ago•9 comments

Show HN: I made an open-source Rust program for memory-efficient genomics

https://github.com/logannye/rosalind
14•logannyeMD•18h ago•0 comments

Show HN: Cancer diagnosis makes for an interesting RL environment for LLMs

43•dchu17•1d ago•20 comments

Show HN: Shadowfax AI – an agentic workhorse to 10x data analysts productivity

https://shadowfax.ai/?from=hn
13•diwu1989•8h ago•0 comments

Show HN: I built a platform where audiences fund debates between public thinkers

https://logosive.com
40•mcastle•1d ago•36 comments

Show HN: I built whatstype.org – a free personality test site

https://whatstype.org/en
5•olivefu•10h ago•4 comments

Show HN: Cactoide – Federated RSVP Platform

https://cactoide.org/
67•orbanlevi•2d ago•28 comments

Show HN: Akashi Notari – On-chain Proof of Existence for any file in 60s for <$1

https://akashi-notari.com/
3•takeshi_w•11h ago•0 comments

Show HN: SkillGraph – Open-source agentic framework with skills instead of tools

https://github.com/tejassudsfp/skillgraph-backend
13•tejassuds•1d ago•0 comments

Show HN: Data Formulator – interactive AI agents for data analysis (Microsoft)

https://data-formulator.ai/
36•chenglong-hn•2d ago•11 comments

Show HN: Tusk Drift – Open-source tool for automating API tests

https://github.com/Use-Tusk/drift-node-sdk
55•Marceltan•2d ago•17 comments

Show HN: ChatExport Structurer – parse ChatGPT/Claude exports into queryable SQL

https://github.com/1ch1n/chat-export-structurer
5•chan1•1d ago•0 comments

Show HN: Venturu – Zillow for the market of local businesses

https://www.venturu.com
33•lifenautjoe•2d ago•36 comments

Show HN: What Is Hacker News Working On?

https://waywo.eamag.me/
223•eamag•1w ago•51 comments

Show HN: Chime – Full-screen meeting alerts for time blindess (macOS)

https://www.usechime.app/
3•tsormed•18h ago•0 comments

Show HN: Creavi Macropad – Built a wireless macropad with a display

https://creavi.tech/blog/creavi-macropad-build-log/
31•cmpx•2d ago•7 comments

Show HN: ShellDash – Browser server dashboard with SSH and globe monitoring

https://shelldash.com
4•mannders•1d ago•0 comments

Show HN: Gametje – A casual online gaming platform

https://gametje.com
111•jmpavlec•2d ago•40 comments

Show HN: A game of higher or lower using GitHub stars

https://higher-lower.muxo.ai/
2•alexander2002•7h ago•2 comments

Show HN: Made MadLibs-style game to play with my kids

https://www.storygaps.org/
2•ronbenton•20h ago•0 comments

Show HN: Open-Source LaTeX OCR, Alternative to Mathpix/SimpleTex

https://texocr.netlify.app/
5•alephpi•1d ago•0 comments

Show HN: Invisitris a Tetris-like game, where the placed pieces become invisible

https://invisitris.bitechunk.com/
4•eddguzzo•21h ago•2 comments

Show HN: YaraDB – Lightweight open-source document database built with FastAPI

https://github.com/illusiOxd/yaradb
10•ashfromsky•1d ago•1 comments

Show HN: Hephaestus – Autonomous Multi-Agent Orchestration Framework

https://github.com/Ido-Levi/Hephaestus
80•idolevi•1w ago•14 comments

Show HN: The Prompt Engineering Bible – Complete Guide to AI Communication

https://dimitriosmitsos.gumroad.com/l/prompt-engineering-bible
3•Cranot•23h ago•0 comments

Show HN: KV Marketplace – share LLM attention caches across GPUs like memcached

https://github.com/neelsomani/kv-marketplace
2•nsomani•1d ago•1 comments
Open in hackernews

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

https://github.com/moustafa-nasr/fahmatrix
46•mousomashakel•6mo 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•6mo 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•5mo 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•6mo 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•6mo 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•6mo ago
Polars and duckdb interoperate nicely and can enable this flexibility
theanonymousone•6mo ago
Does Polars have a Java library?
mousomashakel•5mo 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•5mo 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•5mo 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•6mo ago
What about Tablesaw, Apache Arrow? How does this compare ...
mousomashakel•5mo 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•6mo ago
Nice!

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

mousomashakel•5mo 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.