London Scala User Group

Agenda
6:00pm - 🥤 Doors open. Come along and grab a drink!
6:40pm - 🗣️ Zainab Ali: Taking the plunge: a deep dive into streaming with fs2
7:20pm - 🍕 Intermission: Join us for some free food and drinks! Vegan, vegetarian and gluten-free options are provided. Let us know if you'd like something special - we'd be happy to accommodate.
7:50pm - 🗣️ Kannupriya Kalra & Rory Graves: Scala Meets GenAI: Build the Cool Stuff with LLM4S
8:30pm - 🥤 Socialising: Grab a drink and let's discuss the talks.
9:00pm - 🍻 Join us in The Butcher's Hook and Cleaver pub to discuss the talks!

🌐 This event has a live stream. Join the webinar at 6:40PM. Watch this space for more details.

🗣️ Zainab Ali: Taking the plunge: a deep dive into streaming with fs2
We often think of streaming as a niche concern: something that occurs in large scale data-intensive systems, or event driven architectures. But streams are a lot more versatile than you might suspect. In fact, they form the cornerstone of almost every useful Scala application.

In this talk, we’ll navigate the rich waters of streaming.

Using the lens of fs2, a functional streaming library, we’ll explore how certain problems can be expressed much more easily using streams. We’ll spot the more obvious streams in event-based systems and data processing, webservers and databases, but also discover more subtle streams in time-based processes and concurrency challenges.

We’ll learn what streams are for, how to think about them, when to use them and when not to. By the end, you’ll see a streaming framework as a simple and versatile tool in your toolbox, and will feel confident putting it to use in any area of your codebase.

⭐ Zainab Ali ⭐
Zainab Ali is a functional programming trainer, open source contributor and organizer of the London Scala User Group. For the past seven years, she’s helped developers master the art of functional programming in Scala. The author of Functional Stream Processing in Scala, she’s particularly interested in the art of reasoning through concurrent systems and incremental processes.

🗣️ Kannupriya Kalra & Rory Graves: Scala Meets GenAI: Build the Cool Stuff with LLM4S
Can you build the coolest GenAI apps in Scala? Yes! LLM4S is the batteries-included toolkit for all your AI needs—basic LLMs, Retrieval-Augmented Generation (RAG), image understanding, and agentic workflows.
In this talk, Kannupriya Kalra, co-creator and maintainer of LLM4S, shares the story of how and why this toolkit was built, the key ideas behind it, and how community-driven development through Google Summer of Code helped expand its capabilities.
We’ll walk through live demos—from basic LLM calls and RAG search to image processing and AI-driven code writing. If you’re curious about building powerful, production-ready GenAI applications in Scala, this session is for you.
With GenAI and LLM4S, you can build:

• Conversational agents and intelligent chatbots
• Retrieval-Augmented Generation (RAG) over custom datasets
• Automated code generation and Scala-aware developer tools
• Image captioning, generation, and understanding
• PDF and document summarization and question-answering
• Semantic search engines for unstructured data
• AI agents that plan, reason, and call tools
• Multi-step workflows combining text, data, and APIs
• Content generation for blogs, reports, and marketing
• Scalable GenAI-powered backend services in pure Scala

Whether you’re building tools for developers, enterprises, or creative applications, this talk will show you how to harness the full power of GenAI in the coolest language: Scala.

⭐ Kannupriya Kalra ⭐
Kannupriya Kalra is the org admin for the Google Summer of Code 2024 and 2025 programs with Scala Center, where she plays a key role in shaping the future of Scala open-source contributions. As a mentor for both years, she has guided projects such as Scaladex, Scala CLI, and LLM4S. In 2024, she represented Scala Center at the Google Open Source Conference in Sunnyvale, California. With a passion for knowledge sharing, Kannupriya has delivered talks in four countries, inspiring developers globally. She is also the maintainer of LLM4S, a Scala-first AI toolkit she co-created with Rory Graves. With over 10 years of experience in functional programming, Kannupriya has worked on scalable software solutions at Sky in London, focusing on backend development with functional Scala. She has also contributed to various Scala projects in India, specializing in data engineering, and has expertise in Scala, Akka, and big data technologies.

⭐ Rory Graves ⭐
A builder of tools, fighting to balance performance and code clarity. Rory has been passionate about computing for as long as he can remember — starting with writing games in BASIC far too many years ago. Over a 30+ year career, he has worked across a vast range of systems at every scale, from embedded systems to distributed internet-scale bidding engines. His experience spans industries, company sizes (from two-person startups to multinational corporations), and programming paradigms. A long-time advocate of Scala, Rory has contributed to numerous open-source projects, including performance optimizations in the Scala compiler. Today, he works in a hybrid role supporting applied AI and ML research while continuing to mentor developers and share knowledge through public speaking. Outside of software, Rory is a martial artist, a windmill tour guide, and a passionate mentor of programming and public speaking.

Frequently Asked Questions
I can’t get into The Trade Desk!
To attend our event hosted by The Trade Desk you will need to be registered with the building. Please provide your name and email address when registering.
Before the event, you’ll receive an email from “One Bartholomew” titled “Your appointment at One Bartholomew”. If this is your first time at The Trade Desk, you will need to fill in an online form. Following this, you will be sent a QR code.
On arrival, enter the building and scan the QR code at the barriers to access and see the lift on the display (A-F). The lift will send you to the 10th floor.
After exiting the lift, make your way to The Trade Desk reception.
You can find detailed instructions here .
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📜 All London Scala User Group events operate under the Scala Community Code of Conduct.
We encourage each of you to report the breach of the conduct, either anonymously through this form or by contacting one of our team members. We guarantee privacy and confidentiality, as well as that we will take your report seriously and react quickly.

Are you going to Scala Days ?

🚂 Let's make the trip together on the Scala Days Train Jam!

Join fellow Scala developers and hack on projects on the train. The train jam starts at London, goes via Paris, and ends at Lausanne.

If you're a frequent traingoer or just taking your first steps in sustainable travel, the train jam is the journey for you!

Agenda ​

• 8:15 Assemble at St Pancras
• 9:31 Take the Eurostar to Paris
• 12:58 Arrive in Paris and head to Gare de Lyon
• 14:18 - Take the TGV to Geneva
• 17:29 - Arrive in Geneva
• 17:54 - Leave Geneva
• 18:37 - Arrive in Lausanne 🎉

Questions
How much is the train fare?
If you book now, it’ll be roughly £230 - £250 depending on whether you’re booking a return.

How do I book tickets?
Read our guide for train jammers for a step by step booking process. ​

Is there Wifi on the train?
Yes! There’s Wifi and generally good signal on the Eurostar, TGV, and in Gare de Lyon, where we’ll spend most of our journey.

What will we jam on?
Whatever you like! Along the way we’ll contribute to OSS projects, or hack on fun and interesting ideas.

I’ve never taken the train in Europe. Is it hard?
Not at all! Taking the Eurostar and TGV is very smooth. The difficult bit is booking tickets (see How do I book tickets? above). The most tricky part of our journey is crossing Paris via the metro, and we'll do that as a group.

Why are you going a day early?
We’re going in time for the Scala Days workshops and Scala Bridge. If you’re not attending either of these, we strongly encourage you to spend the day hacking together, or to join in other events. ​

I want to go by train, but can't take this one. Are there other trains I can take?
Of course, although you might not be with other jammers. Our guide for train jammers has some alternative journeys already planned out.

📜 All London Scala User Group events operate under the Scala Community Code of Conduct.
We encourage each of you to report the breach of the conduct, either anonymously through this form or by contacting one of our team members. We guarantee privacy and confidentiality, as well as that we will take your report seriously and react quickly.