ReactJS Barcelona

ReactJS Barcelona - June 2026

Wed, Jun 10 · 6:30 PM CEST

New Relic oficinas, Torre Glories, Av. Diagonal, 211, Sant Martí, 08018 Barcelona, Barcelona, ES

June Meetup is here! Let's gooo!

Do you want to learn more about Micro Frontends? Then we have some experts in the house! Check it out 👇
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18:30: Welcome
Grab a seat until everybody arrives!

18:45 Intro by Hosts Neciu Dan & Erik Grijzen

19:00 8 Years of Micro Frontends @ New Relic: Lessons Learned
Speaker: Erik Grijzen, Principal Software Engineer

New Relic started implementing a Micro Frontend architecture about eight years ago, before the concept of Micro Frontends even existed as an architectural pattern. Over the years, we’ve learned hard-won lessons on designing, scaling, and maintaining Micro Frontends. We will go over some of the most important architectural decisions that need to be considered and see how they have affected us. We will also cover some of the most common anti-patterns and discuss practical strategies to avoid them, illustrated with real-world examples.

19:30 Developing a micro-frontends open source framework
Speaker: Natalia Venditto, Engineer and hands-on architect at Adobe

In this talk, I will talk about the technical challenges of building and maintaining an open source framework. What features we have prioritized while using it and solving real life problems, how we have monkey patched the browser to work on top of the web platform and make it agnostic and how we are working to port some of those features as standards

19:50: Drinks and networking!
Do you want to talk at this meetup? Reach out to Dan Neciu on LinkedIn

And please help us spread the news and grow the community:

20:55 Meetup finished

(FOR EARLY ACCESS: WE ALWAYS POST FIRST ON SOCIAL MEDIA)

Twitter(X)
BlueSky
LinkedIn
Instagram

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Sponsors:

New Relic

New Relic arms businesses with the trust and confidence required to thrive in the AI era. The New Relic Intelligent Observability Platform is the only open, AI-strengthened platform designed to unify telemetry and business outcomes, bringing intelligence and automated actions to the most complex digital environments. The platform shifts teams from reactive firefighting to intelligent orchestration, leveraging AI-driven automation to optimize technology spend and protect revenue in real-time. That’s why global leaders—Adidas Runtastic, Domino’s, Ryanair, Swiggy, Topgolf, and William Hill—run on New Relic to drive innovation and deliver exceptional customer experiences.
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ReactJS Barcelona - Lodgify June

Tue, Jun 30 · 6:30 PM CEST

Lodgify New office, Av. de Josep Tarradellas, 20, L'Eixample, 08029 Barcelona, Barcelona, ES

New Meetup is here! Let's gooo! We have some amazing speakers, and pizza and beer will be available after the event.
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18:00: Welcome
Grab a beer, a snack, and a seat until everybody arrives!

18:30 Intro by Host Neciu Dan

18:45 The Package Was Fine Yesterday: Why Your Dependencies Are a Security Risk - and What to Do About It
Speaker: Vitaly Baev, Senior Frontend Engineer @ Revolut

Every JS project relies heavily on third-party code. Some of it runs during install, some in CI, some inside the editor, and some with access to real credentials. This talk explains how recent supply-chain attacks abused that trust and what developers can do to reduce risk without stopping delivery.

19:20 Under the hood: How V8 powers your JS apps (and why you should care)
Speaker: Gwyneth Rose, Senior Engineer at Lodgify

You've transpiled your JavaScript, minified it, chunked it, and sent it to your CDN. But what happens when the code actually hits the browser? In this talk, we'll walk through the workings of V8, the JavaScript engine that powers Chromium-based browsers and Node.js. We'll focus on its JIT (just-in-time) compiler, how it learns about your code at runtime, and how it optimizes for performance as you use a web app. We'll also go over concrete techniques to make the JIT compiler's job easier, helping you stay in V8's fastest execution path.

19:50: Drinks and networking!

20:45 Meetup finished

Would you like to talk at the next meetup? Reach out to Dan Neciu on LinkedIn

And please help us spread the news and grow the community:

(FOR EARLY ACCESS: WE ALWAYS POST FIRST ON SOCIAL MEDIA)

Twitter(X)
BlueSky
LinkedIn
Instagram

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Sponsors:
Lodgify

Lodgify is a constantly growing tech start-up, focused on building vacation rental software that enables vacation rental owners to independently manage and market their business online. We do so by providing them with easy-to-build websites, including a booking and reservation system, various synchronisation options, and payment collection options. We are +350 Lodgifiers strong, and you can find us working in Barcelona and all around the world! We are working in a hybrid mode and provide our team members with an option to work from home and spend additional time with their family, friends and pets. With more than 60 nationalities, we celebrate diversity daily! With 43% of female and 57% of male employees we are striving to establish a gender balance. Actions are continuously taken to include more women in our Tech teams.

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