Marcel is available for hire
Hire MarcelMarcel Hageman
Verified Expert in Engineering
Front-end Developer
Amsterdam, Netherlands
Toptal member since April 12, 2021
Bio
Marcel is a seasoned front-end developer with over 20 years of professional experience—six as a consultant—delivering projects for successful startups, scale-ups, and large corporations like Apple and Abn Amro. Marcel specializes in developing progressive web applications and has a slight preference for React and Vue.js recently.
Portfolio
Abn Amro
JavaScript, Vue, HTML5, CSS3, Git, ECMAScript (ES6), User Interface (UI), Jira...
Apple
React, React Native, HTML5, CSS3, Git, ECMAScript (ES6), Jira...
Theorem
React, React Native, Redux, TypeScript, Vue, HTML, JavaScript, CSS, Ruby, HTML5...
Experience
- JavaScript - 20 years
- HTML - 20 years
- CSS - 12 years
- Sass - 7 years
- React - 7 years
- TypeScript - 5 years
- Redux - 5 years
- React Native - 4 years
Availability
Part-time
Preferred Environment
React, HTML, CSS, JavaScript, TypeScript, Vue, Redux, Reselect, Sass
The most amazing...
...thing I've learned was when I did A/B-testing on the effects of converting bug fixes, I found out that some bugs really are features. Profitable ones.
Work Experience
Senior Front-end Engineer
2021 - 2022
Abn Amro
- Ran one-on-one interviews with current employers to document their experiences working for ABN AMRO. This report led to vital new insights for those in higher management who were entirely unaware of many issues.
- Reported on technical findings during my first few months working for ABN AMRO, many of which were issues that bothered a lot of other people who did not take the time and effort to highlight these to the right people.
- Set into motion a wave of changes in both the company's technical aspects and personal guidance. Juniors now get more attention and time from their seniors.
- Changed the way development teams interacted with visual and user experience design teams, streamlining communication between them and increasing efficiency and visual quality of the end-product.
Technologies: JavaScript, Vue, HTML5, CSS3, Git, ECMAScript (ES6), User Interface (UI), Jira, User Experience (UX), Mantine, Redux Thunk, Redux Toolkit, Web Components, Front-end, Front-end Architecture, Front-end Design, Front-end Development, UX Design, Leadership, MySQL, Minimum Viable Product (MVP), Styled-components, UI Animation
Senior Front-end Engineer
2020 - 2021
Apple
- Developed a number of web and native applications with a small team of highly skilled engineers; also finished several projects to the liking of the client months before the deadline.
- Created and implemented fundamental technologies for a brand new design to the pixel-perfect design standards of Apple, for a client-facing application that was to be used in Apple stores around the world.
- Taught internal Apple engineers to master the, at that point, relatively new React APIs such as hooks and context.
- Led a team of external consultants towards using React Native in lieu of recruiting their own iOS-developers, increasing visibility of their abilities, and expanding on the tasks the team could take on and finish.
Technologies: React, React Native, HTML5, CSS3, Git, ECMAScript (ES6), Jira, User Interface (UI), User Experience (UX), Material UI, Mantine, Redux Thunk, Redux Toolkit, Node.js, Front-end, Front-end Architecture, Front-end Development, UX Design, Leadership, PostgreSQL, Figma, Minimum Viable Product (MVP), Styled-components, UI Animation, Live Chat, Video Streaming, Mobile Development, Mobile App Design
Senior Front-end Engineer
2019 - 2020
Theorem
- Pitched increased communication and a retrospective of an entire project as it were, within teams, after finishing up the work on clients.
- Highlighted several opportunities for improvement in the setup of existing projects—leading to internal changes that ended up improving the workflow for developers and our value to our clients.
- Assisted in the hiring of other frontend engineers, reviewing application profiles, interviewing candidates via video calls, and reviewing their job application projects.
- Worked on in-house developed open-source tools by reviewing the code of external contributors and increasing online project visibility.
Technologies: React, React Native, Redux, TypeScript, Vue, HTML, JavaScript, CSS, Ruby, HTML5, CSS3, Git, ECMAScript (ES6), Jira, User Interface (UI), User Experience (UX), Material UI, Mantine, Redux Thunk, Redux Toolkit, Web Components, Next.js, Front-end, Front-end Architecture, Front-end Design, Front-end Development, UX Design, Leadership, MySQL, PostgreSQL, Figma, Google Cloud Platform (GCP), Discord, Minimum Viable Product (MVP), Styled-components, UI Animation, Parallax, Live Chat, Video Streaming, Mobile Development, Mobile App Design
Senior Front-end Engineer
2019 - 2020
Couchbase
- Switched up the entire front-end architecture from a very inefficient developer workflow to one that incorporated time-saving and developer-friendly open-source tools.
- Completed a redesign and technical rework of the architecture for the new Couchbase dashboard ahead of schedule.
- Assisted in recruiting and onboarding new front-end engineers from all over the world, increasing team velocity, and–as planned–successfully phased the team of external consultants out so the client could take over with their own employees.
Technologies: React, Redux, TypeScript, Amazon Web Services (AWS), Azure, Google Cloud, Couchbase, HTML5, CSS3, Git, ECMAScript (ES6), Jira, User Interface (UI), User Experience (UX), Material UI, Redux Thunk, Node.js, Front-end, Front-end Architecture, Front-end Design, Front-end Development, UX Design, MySQL, PostgreSQL, Figma, Google Cloud Platform (GCP), Discord, Minimum Viable Product (MVP), Styled-components, UI Animation, Live Chat
Senior Front-end Engineer
2018 - 2019
Tele2
- Implemented the new visual identity of the company on day one to demonstrate the capabilities of the front-end team to company stakeholders.
- Set up a new CI/CD pipeline that significantly sped up deployment cycles.
- Replaced an entire testing department for noncritical releases which sped up release intervals from once every four months to several times per day.
- Responsible for coaching less senior team members in order to safeguard coding quality and excellence.
- Implemented and used specialized tooling to take After Effects animations to the web.
Technologies: React, JavaScript, Lottie, After Effects CC, HTML5, CSS3, Git, ECMAScript (ES6), Jira, User Interface (UI), User Experience (UX), Material UI, Redux Thunk, Front-end, Front-end Architecture, Front-end Design, Front-end Development, Leadership, MySQL, Figma, Discord, Minimum Viable Product (MVP), Styled-components, UI Animation, Parallax, Live Chat, Mobile Development, Mobile App Design
Senior Front-end Engineer
2018 - 2019
Quin Doctors
- Created an MVP to prove the viability of the clients' software—leading to a renewed contract and a successful ongoing startup.
- Polled active users of the native app at health care facilities to get a feel for our UX assumptions and correct use of accessibility tools.
- Introduced TypeScript as a type safeguard in the codebase post-MVP.
- Implemented GraphQL to work together with the Kotlin microservices API.
- Built an administrative panel for internal data scientists and company stakeholders using Node.js.
Technologies: React, React Native, TypeScript, Kotlin, Node.js, HTML5, CSS3, Git, ECMAScript (ES6), Jira, User Interface (UI), User Experience (UX), Material UI, Redux Thunk, Front-end, Front-end Architecture, Front-end Design, Front-end Development, UX Design, MySQL, Figma, Google Cloud Platform (GCP), Minimum Viable Product (MVP), UI Animation, Mobile App Design
Senior Front-end Engineer
2017 - 2018
Mendeley
- Successfully proposed a new server-side rendered solution (Next.js) for the jobs section of the Mendeley website, which quickly got adopted by other teams after.
- Took part in video calls with User Experience specialists, testing the end-users with tasks, seeing the effects of our frontend changes and additions on their daily tasks.
- Replaced the existing Mendeley Jobs section over time, using a gradual deployment strategy by slowly replacing existing pages instead of going for a big-bang approach.
Technologies: React, Redux, CSS, JavaScript, HTML, Next.js, HTML5, CSS3, Git, ECMAScript (ES6), User Interface (UI), Redux Thunk, Front-end, Front-end Architecture, Front-end Design, Front-end Development, UX Design, Leadership, Figma, Minimum Viable Product (MVP), Styled-components, UI Animation, Parallax, Live Chat
Senior Front-end Engineer
2013 - 2016
ICEMOBILE
- Cloned the native (iOS and Android) apps into a progressive web application. This led to a newfound acceptance of web solutions in an otherwise native-first type of company.
- Set up a back end for an internal startup project—leading a demo that eventually caused the entire company to switch their Java back end entirely to Node.js instead.
- Managed a team of front-end developers working on internal tooling that served as content-management systems for native and web applications alike.
- Got an internal startup off the ground that would eventually separate and become its own successful company.
Technologies: React, Web Components, Ember.js, Backbone.js, Node.js, MongoDB, HTML5, CSS3, Git, ECMAScript (ES6), Jira, User Interface (UI), User Experience (UX), Redux Thunk, Front-end, Front-end Architecture, Front-end Design, Front-end Development, UX Design, Leadership, MySQL, PostgreSQL, Minimum Viable Product (MVP), UI Animation, Parallax, Live Chat, Video Streaming, Mobile Development, Mobile App Design
Senior Front-end Engineer
2012 - 2013
Booking.com
- Reported an idea that would turn out to be one of the most successful and lucrative A/B-test of that year, which was implemented by another colleague in the team responsible for that specific part of the Booking.com webpage.
- Learned a lot about A/B-testing, internationalization, and differences between cultures around the world, and how they respond differently to various amounts of stimuli on web pages.
- Pitched Agile methodology to a team that was unfamiliar with it.
- Suggested updated details on landing pages for specific cities with additional information that would be relevant for people visiting.
- Oversaw the correct implementation of over 40 different translations of new features that I had suggested.
Technologies: Perl, HTML, JavaScript, A/B Testing, Multivariate Testing, User Experience (UX), eCommerce, HTML5, CSS3, Git, ECMAScript (ES6), User Interface (UI), Front-end, Front-end Design, Front-end Development, UX Design, UI Animation
Front-end Engineer
2008 - 2011
Topicus
- Created a tool to allow medical specialists to review high-resolution images, zoom in and out, and add notes.
- Implemented a precursor to modern progressive web applications—namely Google Gears—to allow mobile doctors to use a web application even when no internet was available. This data would be synchronized as soon as the internet was available again.
- Oversaw the setup of an internal CSS framework that we would use for internal projects.
- Created a tool to manage XML-based language files and open them up to nontechnical people to easily work with translations, seeing their changes reflected in server-side rendered screenshots before publishing.
- Implemented a high-speed medical application in Microsoft Silverlight.
- Trained junior back-end developers to properly implement database indexes and not using unnecessary subqueries, which reduced the loading time of an emergency medical worklist (used in ERs) down from 30 seconds to under half a second.
Technologies: Apache Wicket, Java, HTML, jQuery, JavaScript, CSS, Gears, Microsoft Silverlight, HTML5, CSS3, Git, User Interface (UI), User Experience (UX), Front-end, Front-end Architecture, Front-end Design, Front-end Development, UX Design, MySQL, UI Animation, Parallax, Live Chat
Web Developer
2001 - 2007
Pepper Interactive
- Implemented a Flash solution to show live telemetry from the 24 Hours of Le Mans race, giving thousands of visitors a one-of-a-kind and at the time unique insight into the details of the race.
- Developed and maintained a homemade CMS (based on XML and XSLT) using classic ASP to render it server-side into valid XHTML.
- Created over 200 different websites, both national and international.
- Responsible for fine-tuning hundreds of email templates that worked on various popular email clients of that time.
- Visually designed several dozens of websites, implemented the design into code, and presented the results to clients.
- Worked with a client that was the first clothing company in the Netherlands to have in-store pillars with touch screens for customers to look at inventory, obtain styling advice, get discounts, and more.
- Created, for a startup company, a solution for exchanging large files via email. The solution involved plugins for major email clients, as well as an online website for paid registrations, downloading of files, authentication, and management of users.
Technologies: jQuery, Active Server Pages (ASP), C#, .NET, Microsoft SQL Server, HTML, JavaScript, CSS, HTML5, CSS3, User Interface (UI), Front-end, Front-end Architecture, Front-end Design, Front-end Development, UX Design, MySQL, PostgreSQL, UI Animation, Parallax, Live Chat, Video Streaming
Experience
Startup: FashionTrade
A well-funded startup in Amsterdam's city center with a view over the canals, visually stimulating to work at and technologically fascinating in many ways. After having always worked as a salaried employee up until this point, this was my first job as a consultant—an amazing one.
On my first day, I had my first useful commit pushed before lunch. During my time at FashionTrade, I learned many things from more experienced consultants and had an amazing interaction working together with a talented UX designer who I later learned was also part of Toptal.
My involvement as their second front-end developer was to speed up the velocity of their Scrum board. From a minimal skeleton project, we took only a few months to turn it into software that would be taken to market.
I learned a lot about filling in the role as a hands-on consultant; I also took the opportunity to learn from more experienced consultants on how to write efficient, scalable, and developer-friendly code.
One of my biggest contributions to the team and project was my unique (before and after) experience working with the aforementioned UX designer from Toptal, elevating the design to new heights.
On my first day, I had my first useful commit pushed before lunch. During my time at FashionTrade, I learned many things from more experienced consultants and had an amazing interaction working together with a talented UX designer who I later learned was also part of Toptal.
My involvement as their second front-end developer was to speed up the velocity of their Scrum board. From a minimal skeleton project, we took only a few months to turn it into software that would be taken to market.
I learned a lot about filling in the role as a hands-on consultant; I also took the opportunity to learn from more experienced consultants on how to write efficient, scalable, and developer-friendly code.
One of my biggest contributions to the team and project was my unique (before and after) experience working with the aforementioned UX designer from Toptal, elevating the design to new heights.
Skills
Libraries/APIs
React, Reselect, jQuery, Mantine, Parallax, Node.js, Backbone.js, Vue
Tools
Redux Thunk, Git, Redux Toolkit, Figma, After Effects CC, Microsoft Silverlight, Jira
Languages
HTML, CSS, JavaScript, Sass, Active Server Pages (ASP), HTML5, CSS3, ECMAScript (ES6), TypeScript, Kotlin, Perl, Java, Ruby, C#
Frameworks
Redux, React Native, Next.js, Material UI, Svelte, Ember.js, Apache Wicket, .NET
Paradigms
UX Design, Mobile Development, Mobile App Design
Platforms
Google Cloud Platform (GCP), Amazon Web Services (AWS), Azure
Storage
MySQL, PostgreSQL, MongoDB, Microsoft SQL Server, Google Cloud, Couchbase
Other
User Interface (UI), Front-end, Front-end Architecture, Front-end Design, Front-end Development, Minimum Viable Product (MVP), Styled-components, UI Animation, SvelteKit, Web Components, A/B Testing, Multivariate Testing, User Experience (UX), Gears, Leadership, Live Chat, Video Streaming, Lottie, eCommerce, Discord
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