Sean Roennau-Wergen

Front-End Developer

Salary / Daily rate

Paris, France

Mobility: Paris

Freelance, open to permanent contract

Can come onsite

Skills

JavascriptTypescriptTailwind CSSReactAngularWeb DesignGitHubHTMLBootstrapNextVercelGitJenkinsRESTful APIsSassNodeCSSReduxMongoDBBitbucketPostmanSwagger/OpenAPIWebpackA/B TestingScrumConfluenceUser ResearchJiraSEODesign SystemFigmaWorkday

Languages

English (Native)FrenchGerman

About me

Intro

Previously a language teacher, now a front-end developer with expertise in React, HTML/CSS, and JavaScript, with recent experience developing reactive interfaces at Abeille Assurances. Specialised in pixel-perfect UI/UX integration, Design System management, and performance optimisation. I deliver cross-platform consistent solutions with strong focus on accessibility and responsive design.

Links

Work experience

Frontend Developer

Abeille Assurances

Oct 2023 - Oct 2025

2 years 1 month

92270 Bois-Colombes, France

UI Component Creation: Development of reactive interfaces using HTML, CSS, JavaScript, and Angular, with a constant focus on performance, accessibility, and cross-platform consistency. Design System Evolution: Updating and enriching the internal Design System following the creation or modification of components. Pixel-Perfect Integration: Faithful translation of UX/UI mockups into HTML/CSS code, with fine-tuned styling adjustments based on functional or responsive needs. Technical Collaboration: Regular exchanges with back-end developers and product teams to ensure proper implementation of mockups and overall coherence. Debugging & Optimization: Identifying and resolving integration issues, particularly those related to responsiveness or unexpected behaviors. A/B Testing: Continuous improvement of user journeys through targeted DOM manipulations in JavaScript as part of A/B testing campaigns.

Business English Trainer

ÉLYSÉES LANGUES

Sep 2019 - Mar 2023

3 years 7 months

Paris, France

Teaching one-to-one or in a group of corporate personnel at the centre, at the clients' place of work or via videoconference. Levels: Absolute beginner to advanced. Pedagogy prioritised on grammatical precision, oral practice and targeted situations.

TOEIC English Teacher

Supméca – Institut supérieur de mécanique de Paris

Feb 2020 - May 2021

1 year 4 months

Teaching a group of aspiring engineering students in preparation for their TOEIC exams. Self-developed interactive pedagogy that was suitably adapted to both the physical and virtual classroom. Marking and grading of assignments.


Education

OpenClassrooms

RNCP Niveau 6

2023 - 2025

2 years 1 month

Nottingham Trent University

Bachelor of Arts - BA

2013 - 2017

5 years

Beijing Language and Culture University

Graduated

2016 - 2016

1 year

University of Potsdam

2015 - 2016

2 years


Licenses & certifications

Responsive Design

Issued: Aug 2023

Certified by FreeCodeCamp

Portfolio

Refonte du Design System interne chez Abeille Assurances

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