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Quanta Live: Building Local AI Search with pgvector & LangChain4j - Part 2

Johannes Rabauer @rabauer.bsky.social · 3d

No cloud, no GPUs, no expensive APIs.
Just open-source tools working together to make local AI useful and fun.

I am still adding a few finishing touches, but the core search flow is already complete.

Building Quanta (Part 2) – Vector Search with Quarkus, pgvector & OllamaIn this session, we’re diving deep into the brains of Quanta — the part that makes it...

Johannes Rabauer @rabauer.bsky.social · 3d

In this session we:
🧩 Extracted text with Apache Tika
🧠 Created embeddings using Ollama (LLaMA 3.2)
💾 Stored them in PostgreSQL with pgvector
🔍 Queried files semantically with Quarkus and LangChain4j

And it works beautifully.

Johannes Rabauer @rabauer.bsky.social · 3d

Quanta Part 2 is done! 🎉
We now have a fully working AI file searcher that can vectorize your files and let you search them using natural language.

All running locally with Quarkus, Ollama, and pgvector.

Johannes Rabauer @rabauer.bsky.social · 6d

😱

Johannes Rabauer @rabauer.bsky.social · 7d

Thanks very much, Catherine!
It will be a lot of fun, no matter the outcome 🤦🏻‍♂️🤓

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Johannes Rabauer @rabauer.bsky.social · 8d

Really looking forward to it!

Richard Fichtner 💻☕ @richard.fichtner.dev · 8d

🚀 Next JUG Oberpfalz Meetup: We’re excited to welcome Johannes Rabauer to #JUGOberpfalz for a unique live-coding battle between Spring + Spring AI and Quarkus + LangChain4J. No slides – just clean code, directly compared, open source!

🔗 Register here (free): www.meetup.com/jug-o...

Quanta Live: Building Local AI Search with pgvector & LangChain4j - Part 2

Johannes Rabauer @rabauer.bsky.social · 10d

AI is more accessible than ever. No GPUs, no fancy infrastructure, no giant models needed.
Just you, some open-source tools, and a bit of curiosity. 🤓
Join me live as we build an AI file searcher using Quarkus, Ollama, and pgvector.

🎥 Join here → youtube.com/live/cY2anCL...

Building Quanta (Part 2) – Vector Search with Quarkus, pgvector & OllamaIn this session, we’re diving deep into the brains of Quanta — the part that makes it...

XDEV Commit Cards for Clean Code!

Johannes Rabauer @rabauer.bsky.social · 15d

I'm so happy the idea catches on! I truly look at them every day 🤓

Richard Fichtner 💻☕ @richard.fichtner.dev · 15d

Thank you for the shout-out! If you want to learn about clean code best practices for Java check out the XDEV Commit Cards created by @rabauer.bsky.social

xdev.software/en/news/deta...

xdev.software

Spring AI vs LangChain4J: The Live Coding Duel

Reposted by Johannes Rabauer

Catherine Edelveis @cat-edelveis.bsky.social · 21d

We are going live today, in just 2 hours! See you there😊

Catherine Edelveis @cat-edelveis.bsky.social · 23d

👾Spring AI vs LangChain4J: Live Coding Duel

Join me and @rabauer.bsky.social this Thursday as we bring together #SpringBoot and @quarkus.io in a friendly duel of frameworks for Java LLM apps, covering setup, prompts, streaming, and tool-calling. BYO🍿!

www.youtube.com/watch?v=rBxc...

YouTube video by CyberJAR

www.youtube.com

Spring AI vs LangChain4J: The Live Coding Duel

Johannes Rabauer @rabauer.bsky.social · 23d

Really looking forward to some comparisons between frameworks 🤓

Catherine Edelveis @cat-edelveis.bsky.social · 23d

👾Spring AI vs LangChain4J: Live Coding Duel

Join me and @rabauer.bsky.social this Thursday as we bring together #SpringBoot and @quarkus.io in a friendly duel of frameworks for Java LLM apps, covering setup, prompts, streaming, and tool-calling. BYO🍿!

www.youtube.com/watch?v=rBxc...

YouTube video by CyberJAR

www.youtube.com

Johannes Rabauer @rabauer.bsky.social · 23d

Is there a place with "best-practice-guardrails" or something similar? It seems like an awful chore to think of every possible unwanted in- and output and put that into code...

Reposted by Johannes Rabauer

Quarkus @quarkus.io · 25d

Securing LLM Responses in Java: Guardrails with Quarkus and LangChain4j
Learn how to protect your AI applications from prompt injection, unsafe outputs, and risky prompts with practical guardrail patterns in Quarkus.

www.the-main-thread.com/p/java-quark...

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Johannes Rabauer @rabauer.bsky.social · 27d

It looks like you changed passwords since the leak: I tried to login to localhost:8080 with password "pw", but access was denied 😂

Good for you! :)

GitHub - JohannesRabauer/quanta: ai-file-search - lets you find files in a natural language way and summarizes files

Johannes Rabauer @rabauer.bsky.social · Oct 7

🧠 Open-source & still evolving:
github.com/JohannesRaba...

What would you add next, smarter summaries, multi-agent explorers, or something wild?
#LangChain4j #Quarkus #Ollama #pgvector #ApacheTika #AI #Java #LLaMA3

ai-file-search - lets you find files in a natural language way and summarizes files - JohannesRabauer/quanta

github.com

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Johannes Rabauer @rabauer.bsky.social · Oct 7

Quanta tracks file changes, re-vectorizes updates, and returns instant, intelligent answers; all locally.
We debugged Quarkus quirks, Tika headaches, and got Ollama humming 💪
youtube.com/live/OenMqG5...

Johannes Rabauer @rabauer.bsky.social · Oct 7

Under the hood:
⚡ Next.js (frontend)
☕ Quarkus + LangChain4j (backend brains)
🦙 Ollama (LLaMA 3.2 embeddings)
🐘 PostgreSQL + pgvector
📄 Apache Tika for text extraction from any file type

Johannes Rabauer @rabauer.bsky.social · Oct 7

Just went live building Quanta: an AI-powered file searcher that understands your files 🤖📂
It watches your filesystem, vectorizes docs, and lets you query them in natural language.
Let’s make local AI search actually useful 👇

Johannes Rabauer @rabauer.bsky.social · Oct 7

Favorite input field 😅

Johannes Rabauer @rabauer.bsky.social · Oct 4

Unfortunately because of an emergency in the family i have to postpone the session again...i am really sorry.

Johannes Rabauer @rabauer.bsky.social · Oct 1

Thank you very much! :)

Johannes Rabauer @rabauer.bsky.social · Oct 1

Happy birthday Catherine! :)

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Johannes Rabauer @rabauer.bsky.social · Sep 30

Thanks! I am unsure about PostgreSQL with pgvector, but since i have the most experience with it, i'm willing to try ^^
Why did you choose PostgreSQL, if you did?

Building Quanta – An AI File Searcher with Next.js, Quarkus, Ollama & PostgreSQL (Live Coding)

Johannes Rabauer @rabauer.bsky.social · Sep 29

I’ll be building Quanta live on stream. 🎥
Join, ask questions, and help me shape it as we go.

Follow along — this will be fun. 🚀
www.youtube.com/live/OenMqG5...

#AI #LangChain4j #Quarkus #Nextjs #Ollama #pgvector #LocalAI #LiveCoding

In this live coding session, we’re starting Quanta – an AI-powered file searcher that can watch your filesystem, vectorize documents, and let you search & su...

www.youtube.com