Marcel is available for hire

Marcel Juenemann

Verified Expert in Engineering

Full-stack Developer

London, United Kingdom

Toptal member since April 7, 2022

Expertise

Full-stack Web Development Java JavaScript HTML5 PHP Angular TypeScript Firebase Software Development CSS Android Linux A/B Testing

Bio

Marcel worked at Google for seven years as a senior software engineer and engineering manager. His role on Google Search for Android taught him how to develop scalable software for billions of users and lead projects across large organizations. Marcel is a generalist who can quickly learn new technologies. Through his management role, Marcel also discovered a passion for psychology, emotional intelligence, diversity, and inclusion.

Portfolio

Google

Android, A/B Testing, Management, Career Coaching, Leadership, Diversity...

Zalando

Java, JavaScript, Angular, CSS, HTML5, Spring, PHP, PostgreSQL, Bootstrap...

Experience

Web Development - 10 years
JavaScript - 10 years
HTML5 - 10 years
PHP - 10 years
Java - 10 years
Angular - 8 years
Leadership - 3 years
Diversity, Equity, & Inclusion (DEI) - 3 years

Availability

Part-time

Preferred Environment

Linux, Google Cloud, Git, Google Apps

The most amazing...

...I've experienced is at Google when I collaborated with a few of Chrome's founding engineers. It was a great learning opportunity and a very humbling experience.

Work Experience

Senior Software Engineer

2014 - 2021

Google

Managed the team responsible for the web infrastructure of the Google App for Android. This infrastructure was on the critical path of billions of Google searches every day and supported tens of billions in annual revenue.
Led a rewrite of the Google App's Browser, which required an extensive refactoring of Chrome and involved working with senior directors from Chrome, search, and ads on a daily basis.
Improved load time of Google search result clicks by 3% through various optimization efforts. Worked with the ranking team to integrate page speed insights into the Google ranking.
Designed and implemented new features for internal sales tools (full-stack development).

Technologies: Android, A/B Testing, Management, Career Coaching, Leadership, Diversity, Equity, & Inclusion (DEI), Java, Web Development, Angular, MySQL, Chrome Custom Tabs, Architecture, Full-stack

Software Developer

2012 - 2014

Zalando

Designed and implemented a configuration service for managing runtime configuration. This infrastructure was used by dozens of different teams and included a user-friendly front end that enabled assigning granular access rights.
Led the implementation of a PHP API for Zalando's eCommerce back end and guided an external front-end team on how to build an eCommerce shop using the API.
Bootstrapped the infrastructure for a new team by setting up the front end with Angular and Bootstrap, the back end with Java and Spring, and the database with PostgresSQL. The team grew to 50+ members and kept building on top of this architecture.

Technologies: Java, JavaScript, Angular, CSS, HTML5, Spring, PHP, PostgreSQL, Bootstrap, Full-stack

Experience

Angular Drag & Drop library

I built one of the most popular drag and drop libraries for Angular.JS 1.0. It supported complex nested lists and used the HTML5 drag and drop API. It gained over 2,000 GitHub stars and millions of npm downloads.

Google Search: Suggesting Related Pages

https://www.androidpolice.com/2017/11/06/sliding-people-also-view-card-showing-scrolling-google-app-search-result/

I led the technical design and implementation of a new feature in the Google app for Android that suggests related pages to users while browsing through search results. This required close collaboration with the ranking team that was providing the back end and involved overseeing the launch process, including metric analysis.

Google Guava: Optimized Base64 Encoding by 70%

https://github.com/google/guava/commit/2fe1415c5c2a1ee771a1616cc5d30d12e656026c

Google Guava is one of the most used Java libraries globally and is used by all Java projects inside Google. I rewrote the BaseEncoding class, which made encoding over 70% faster and decoding over 60% faster. This class is used by thousands of projects inside Google and many more outside of Google.

Education

2009 - 2012

Bachelor's Degree in Computer Science

Freie Universität Berlin (FU Berlin) - Berlin, Germany

Skills

Libraries/APIs

Google Apps

Tools

Git

Languages

Java, JavaScript, CSS, HTML5, PHP, TypeScript

Frameworks

Angular, Spring, Bootstrap

Paradigms

Management

Platforms

Android, Linux, Firebase

Storage

PostgreSQL, MySQL, Google Cloud

Other

Chrome Custom Tabs, Drag & Drop, Software Development, Full-stack, Leadership, Web Development, Software Architecture, Software Project Management, Architecture, A/B Testing, Optimization, Career Coaching, Diversity, Equity, & Inclusion (DEI)

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