JSHeroes 2025 | Community Organized JS Conference

Join us in 2025!

JSHeroes is a non-profit community-organized event, held every year in Cluj, Romania. Our goal is to bring together JS and Web/Frontend enthusiasts from all over the world for a single-track two-day conference with: quality content, amazing networking and tons of fun. You bring your ideas and desire to learn, we provide the relaxed atmosphere and the good vibes.

Our 7th edition will take place on the 29th and 30th of May 2025!

Tickets are available on our ti.to page.

Meet our first 2025 speakers

Chelsea Troy ML Ops Engineer Mozilla

Chelsea Troy ML Ops Engineer @ Mozilla

Chelsea is a Machine Learning Operations Engineer at Mozilla, focused on the role of data privacy and scientific rigor in automation. She teaches Python to formerly incarcerated technologists through Columbia University’s Justice Through Code Initiative, and she also teaches at the University of Chicago Master’s Program in Computer Science. She hosts workshops for professional engineers through O’Reilly as well as her personal site, and writes at chelseatroy.com.

Talk: Designing APIs for Complex Libraries
When you build a library that is POWERFUL - can handle use cases in lots of different circumstances - you face a challenge with making that library’s API DISCOVERABLE. Git is a fantastic example of this: it’s a powerful version control library that can solve a LOT of problems for programmers, except that most programmers don’t know 80% of what it does. This isn’t a deficiency in programmers: the library just has a high power to discoverability ratio. For your library to REACH all the use cases it can solve for, your team has to have a discoverability strategy. Join Chelsea to learn about success metrics and implementation options for such a strategy.
Hidde de Vries Front-end and a11y specialist

Hidde de Vries Front-end and a11y specialist

Hidde (@hdv) is a freelance front-end and accessibility specialist, currently working in the NL Design System team at the Dutch government. He is also involved in the W3C’s Open UI Community Group and Accessibility Guidelines Working Group. His favourite programming language is CSS and he strongly believes in a web that puts people first. Hidde writes about these things and more on hidde.blog. In his free time, he works on a coffee table book covering the video conferencing applications of our decade.

Talk: Web platform features with a11y built in?
Josh Goldberg Open Source Maintainer
Josh Goldberg Open Source Maintainer

Hi, I’m Josh! I’m an independent full time open source developer. I work on projects in the TypeScript ecosystem, most notably typescript-eslint: the tooling that enables ESLint and Prettier to run on TypeScript code. I’m also the author of Learning TypeScript (O’Reilly), a Microsoft MVP for developer technologies, and an active conference speaker. My personal projects range from static analysis to meta-languages to recreating retro games in the browser. Also cats.
Talk: Tooling Like It's 2025
TypeScript! ESLint! Biome! Oh my! So many tools exist that we can choose from as modern developers. Do you ever feel like you’re getting lost in a sea of GitHub README.mds and configuration file messes?

Let’s talk about the state of tooling for TypeScript developers in 2025. What are the tools that many developers are finding helpful? How are those tools changing over time to be more helpful (and less annoying to configure)? Why do we even care about tooling when we have TypeScript!?

All those questions and more will be answered. We’ll cover:

The state of common tooling: linters, TypeScript, their integrations together (hello, Rust!)

Some of the great benefits of aggressive static analysis (hello, plugins!)

Miscellaneous other tools such as Knip and TypeChat (hello, AI!)

High-level trends for tooling

After this talk, you’ll be prepared not just to configure your linter and type checker, but you’ll understand why so many developers are excited for that task in the first place.
Lydia Hallie Software Engineer & JavaScript Educator

Lydia Hallie Software Engineer & JavaScript Educator

Lydia Hallie is a software engineer and technical content creator with a focus on React, JavaScript, and web performance. She enjoys sharing technical deep-dives, and strives to make complex concepts accessible to developers of all skill levels.
Miriam Suzanne Oddbird

Miriam Suzanne Oddbird

Miriam is an author, artist, developer, and open web advocate. She’s an Invited Expert with the W3C CSS Working Group, and member of the Sass core team, and a co-founder of OddBird – providing a range of web development and design services, along with in-depth workshops and trainings. Miriam co-authored the specifications for CSS container queries, cascade layers, and scope. Offline, she spends her time making pottery, repairing mechanical clocks, knitting socks, or creating art with Teacup Gorilla & Grapefruit Lab.
Sophie Koonin Web Engineering Lead Monzo Bank

Sophie Koonin Web Engineering Lead @ Monzo Bank

Sophie is the web engineering lead at Monzo Bank in the UK, responsible for the web platform across the organisation and working on internal tooling that powers Monzo’s award-winning customer service.

Building websites since the age of 10, she’s passionate about creating inclusive, accessible and fun websites that people love. Sophie writes about tech & mental health at localghost.dev, builds intentionally useless web apps, and makes music.

Talk: So you’ve decided to do a technical migration
It seems like there’s always a hot new library or framework promising great things. But people often forget about the pain and effort required to move from an old technology to a new one. How long will it take? If you finish, will it be worth it? And if you don’t, could it leave you in a worse place than where you started?

Drawing from my experience of the Typescript migration we recently completed at Monzo I’ll take you through some of the different outcomes of technical migrations and the things we learned along the way.
You? Submit your proposal

And our awesome ambassadors

An amazing group of people that ensure top-notch content at the event every year

Andrei Antal Ambassador

Andrei Antal Ambassador
Andrei Pfeiffer Ambassador

Andrei Pfeiffer Ambassador
Benedek Gagyi Ambassador

Benedek Gagyi Ambassador
Carmen Popoviciu Ambassador

Carmen Popoviciu Ambassador

Carmen is an emoji hyper-user disguised as a web developer in real life. She enjoys building things on the web and does exactly that on the Pages team at Cloudflare. If you are ever stranded on a remote island and have only three attempts to recover your master password, the secret key code is “dance”.
Ioana Chiorean Ambassador

Ioana Chiorean Ambassador

Ioana is an engineer manager flavored in communities, and devrel, that has more than 12 years of experience in tech with a specialization in mobile apps and web. Besides her daily job, she dedicates her time to building tech communities and improving the access to education. She is the Module Owner for Mozilla Reps, one of the alumna of MozTechSpeakers, and stands as an ambassador for CodeWeek at the European Commission.

In her free time, she contributes to Open Source, tech or sports events, and different volunteering programs. all these while enjoying a coffee or a good wine.
Jeremias Menichelli Ambassador

Jeremias Menichelli Ambassador

He developed interest in the web back when a dial-up modem was the fastest thing on the planet. Now, he has more than a decade of experience building web products of all kinds and lately working in design systems, performance, education and community.
Sara Vieira Ambassador

Sara Vieira Ambassador
Tejas Kumar Ambassador

Tejas Kumar Ambassador

Tejas Kumar is an international keynote speaker with an engineering background spanning 22 years, from design to frontend to backend to devops. Today, Tejas shares talks at large with developer communities worldwide, equipping them to do their best work.

Bridging the gap

Our ecosystem has an abundance of technologies, tools, frameworks and services to deliver applications faster than ever before. With new standards and ways of building across multiple platforms, developers have wide toolkit at their disposal. But there’s a growing gap between our projects, with accumulated technical debt and complexity, and the tools and frameworks developed by the community. In 2025, we’re bridging that gap.

Our speakers will present solutions for common industry problems, highlight the strugles with managing complexity, maintainability and scalability and will explore new technologies, frameworks and standards that tackle all these concerns.

At JSHeroes, we always ventured outside the pure language ecosystem, so expect to see a variety of talks covering the entire landscape of web development and JavaScript as a universal programming language.

But of course, we will not neglect the human side of things, in our effort to paint a full picture for the development community in 2025.

A transparency-first community event

We believe that the community and the open-source models are well suited for our core values: learning, teaching and knowledge sharing. Our mission is to inspire other communities with the concept of open-source events.

We’re publishing all data about this conference, in full transparency. We are also available at any time for inquires and we’re really looking forward to sharing our knowledge about organizing international events. This way, whenever a community wants to start something similar, they can build on our knowledge.

Ecma, JSHeroes mascot wearing a space suit

Media partners

The communities that support our event

Venue and facilities

We are hosting the JSHeroes 2024 conference at the Grand Hotel Italia, Vasile Conta Street number 2, Cluj-Napoca, Romania.

See directions on Google Maps.

Meet the team

Ale Retegan

Ale Retegan Organizer

Alexandra is a dynamic and passionate individual who has taken on the role of the main organizer of JS Heroes. With a background in project management and a deep love for the tech industry, Alexandra has a keen eye for detail and an unwavering commitment to excellence, which means that no stone is left unturn and no piece of information about the event is tracked in a spreadsheet.
Alex Moldovan

Alex Moldovan Organizer

Alex is one of the founders of JSHeroes and coordinates the effort behind the content of each edition. During the event, he will occasionally pick up the microphone and introduce speakers, but he prefers to keep a watchful eye over the conference, to make sure everything is on time and the event is as smooth as possible.

He works as a Frontend Engineer at CodeSandbox, where he gets to practice his passion for both sides of the user experience vs developer experience dilemma.
Alex Paușan

Alex Paușan Organizer
Alexandra Mînzat

Alexandra Mînzat Organizer

Alexandra is a lovely “sunny” person, she’s our admin girl, on board with JSHeroes since 2017.

Her aim is to make sure everything is done on time, the speakers arrive and leave safely, and urgent matters are attended to during the entire conference week.
Alexandru Lupu

Alexandru Lupu Organizer
Ana Cojuhari

Ana Cojuhari Organizer
Anamaria Oros

Anamaria Oros Organizer

Ana is a dedicated volunteer who has been involved with the JSHeroes conference from the very beginning. Her initial role was to take care of the traveling arrangements of the conference speakers, earning her the affectionate nickname “trip advisor”. However, Ana’s life changed when she became a mother, which made it challenging for her to continue with her initial responsibilities. Nevertheless, she remained committed to the conference and continued to volunteer her time whenever she could, taking on any tasks that were available.

Despite the challenges of motherhood and the demands of her busy schedule, Ana remained dedicated to the conference and always showed up with a positive attitude and a willingness to help wherever needed. Her hard work and dedication were greatly appreciated by everyone involved, and she was admired for her ability to balance multiple responsibilities and still make time to give back to the community.
Claudia Țicle

Claudia Țicle Organizer

Claudia loves people and has a strong sense of curiosity. Believes that design and technology are changing the world. For 💙JSHeroes💙 she 🌔gravitates towards visual design and content usability.
Daniel Mocan

Daniel Mocan Organizer

Daniel mostly focuses on the JSHeroes local meetups, but during the conference gives a helping hand where it is needed. He is usually in charge of the JSHeroes Blood Donation campaign.

He works as Full Stack JavaScript developer, with React on the frontend and Node on the server side.
Eliza Nițoi

Eliza Nițoi Organizer
Florin Tomozei

Florin Tomozei Organizer

Florin participated at the conference from the beginning and was impressed by the incredible community around it. With his previous volunteering experience, in 2023 he decided to join the team and help.

In the meantime, he works as a software engineer at Wolfpack Digital and occasionally finds some time for one of his passions, photography.
Irina Georgescu

Irina Georgescu Organizer
Melania Moldovan

Melania Moldovan Organizer
Nicoleta Ungur

Nicoleta Ungur Organizer
Oana Muntean

Oana Muntean Organizer
Oana Șipoș

Oana Șipoș Organizer
Radu Blana

Radu Blana Organizer

Radu joined the JSHeroes community in 2023 and never looked back. He appreciates the high level of interest, commitment, and fun that everybody in the JSHeroes ecosystem promotes, and is keen to be at its core for the years to come. He is passionate about everything in the Web space, from the bare bits that built up UIs, to UX research and design, developer productivity, healthy work environments and many more. During the event he helps looking after the speakers, making sure that the flow of the conference is as good on stage as it is back-stage. Radu is a UI Developer turned UX designer and Product Owner, currently setting up the bases of a technology consulting business called Bridgeford.
Vlad Ionescu

Vlad Ionescu Organizer

Vlad has been helping organize the event three years running, being the man behind the scenes. Vlad is also in charge of all social events/parties, so if you want to find out where to get a beer in Cluj, Vlad is your man. You can also come find Vlad if you want to talk about LEGO, basketball or video games.

He works as a Full-Stack Engineer at FanDuel, where he gets to have fun doing a bit of everything.