Past Meetup

Winter party edition: Web IoT, Mass scale JS Refactoring ⛄️🎄🍾

This Meetup is past

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Book your calendars, as there's another AmsterdamJS Meetup coming! Don't miss the 🔥 hottest JS event this winter and prepare for big announcements. 😉

Web Bluetooth and Refactoring JS with JS are going to be the talk of the town thanks to our speakers. In case there's anything you'd like to present to our audience, feel free to submit a talk via our official form:

We're very grateful to this edition's main sponsor Reaktor ( and also to Evolution Gaming ( for their long-term support of the event.

# Event Schedule

18:00 - Doors open - snacks, beer, socialization
19:00 - Introduction and announcements
19:10 - 🗣 "Creating IoT Applications with Web Bluetooth" by Martin Woolley
19:40 - 🗣 "How to refactor JavaScript with JavaScript on a massive scale" by Tijn Kersjes
20:10 - Short break
20:20 - 🗣 "The impostor syndrome aka I'm a fraud" by Claudio Semeraro
21:00 - After-party in pub

## Creating IoT Applications with Web Bluetooth
by Martin Woolley (

10 million Bluetooth devices ship every day, and that figure is rising. Regarded as one of the key, enabling technologies of the IoT, Bluetooth is everywhere and in the summer of 2017, a new Bluetooth technology, Bluetooth mesh networking was released. Bluetooth mesh is used in enterprise and industrial IoT systems and in these environments, web technologies and cloud-based architectures are king.

In this session, we'll review key Bluetooth concepts and capabilities and the Web Bluetooth APIs which let you exploit them. There may even be demos!

About Martin

Martin Woolley is an industry veteran with over 30 years' experience working with computers large, small and ….. getting smaller. He still has a Sinclair ZX81 somewhere. He was a part of the BBC micro:bit team and designed the micro:bit's Bluetooth profile.

## How to refactor JavaScript with JavaScript on a massive scale by Tijn Kersjes (

Refactoring on a massive scale is a different beast. What to do when "find and replace" simply isn't enough? We faced this challenge when we needed to unify the way an initial state of a React component was set across the codebase consisting of thousands of files. This is a story about how we created a faultless commit that touched around 100,000 lines of code. Our solution was to write a program that did the required modifications for us. These kind of programs are often called codemods. Languages and concepts are like tools in a toolbox. Codemods are a new tool to your toolbox.

About Tijn

Tijn is a software engineer at Reaktor. He mainly writes Node.js/React applications, is interested in anything functional or reactive, and is rarely seen without a cup of coffee. After office hours he likes to play around with esoteric compilers.

## "The impostor syndrome aka I'm a fraud" by Claudio Semeraro (

The frontend world is moving at an incredibly fast pace, there is just so much to know that feeling overwhelmed may just be the norm. It doesn't matter if you're a seasoned developer or a junior just starting out, comparing yourself to others will trigger many biases and feeling like a fraud is way more common than you may think. It even has a name: the impostor syndrome.

About Claudio

Full stack JavaScript developer, successfully pretending to know how to code for 15 years now.


# Code of Conduct

By registering to this event you agree to comply with our Code of Conduct

# Contact

If you have any questions about the AmsterdamJS community, or willing to support us as a company and sponsor the next event – reach us at [masked]

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