Senior UI Frontend Developer
Aktualisiert am 20.11.2025
Profil
Freiberufler / Selbstständiger
Remote-Arbeit
Verfügbar ab: 01.12.2025
Verfügbar zu: 80%
davon vor Ort: 0%
CSS
JavaScript
ReactJS
Graphical User Interface
User Experience Designer
User Experience Design
User Interface Designer
User Interface Design
User Interface Entwicklung
ReactJS
Adobe Photoshop
Adobe Illustrator
Sass
German
Limited
English
Native
Portuguese
Native
Spanish
Good

Einsatzorte

Einsatzorte

remote (+200km)
möglich

Projekte

Projekte

3 Jahre 8 Monate
2022-01 - 2025-08

Design and Development of On-Chain AI Chat Platform

Senior Frontend Engineer
Senior Frontend Engineer
  • Led the design and development of the first on-chain AI chat platform, enabling 10k+ users with end-to-end encryption and immutable audit trails.

  • Optimized Svelte-based frontend, reducing latency by 35% for LLM-driven interactions.

  • Partnered with product/security teams to integrate privacy-preserving AI workflows, increasing enterprise adoption.

OnicAI
remote
1 Jahr 7 Monate
2020-06 - 2021-12

Pioneering Generative UI Prototypes and Advanced Data Visualizations

Research Engineer
Research Engineer
  • Pioneered generative UI prototypes, influencing blockchain frameworks later adopted in 3 products.
  • Developed advanced data analysis dashboards, delivering insights for decision-making
  • Conducted UX research, shaping product roadmaps with data-driven insights
Forward Research
remote
6 Monate
2018-10 - 2019-03

Architected data processing platform

Full Stack Engineer graphQL Handlebars.js npm ...
Full Stack Engineer

  • Architected data processing platform handling millions of records daily, improving analytics speed by 40%.
  • Developed ML-driven UI reducing manual effort by 30%.
  • Enhanced enterprise UI speed with Python & Apache Spark integration.

webstorm
graphQL Handlebars.js npm Git D3 JavaScript JavaScript jQuery JSON REST Sass npm webpack
Allianz SE
Munchen
1 Jahr 5 Monate
2017-05 - 2018-09

tech strategy, scaling infrastructure and ensuring platform resilience.

CTO
CTO
  • Directed tech strategy, scaling infrastructure and ensuring platform resilience.
  • Cut downtime by 40% with CI/CD practices and optimized hosting environments.
  • Reduced infrastructure costs by 20% via vendor partnerships.
on request
6 Monate
2017-12 - 2018-05

Implemented mobile app

Senior Frontend Developer html css jsp ...
Senior Frontend Developer

  • Implemented mobile app rebrand with optimized real-time flight workflows, reducing response time by 20%.
  • Boosted mobile performance scores by 25% through iterative testing & tuning.

webstorm
html css jsp sass less jquery javascript git confluence jira JSP
Lufthansa ? Cologne, Germany
10 Monate
2016-09 - 2017-06

UI Frontend Developement

Senior UI Frontend Developer NPM GULP Grunt ...
Senior UI Frontend Developer

  • Redesigned sign-up flow, boosting conversions by 18% and reducing abandonment by 25%.
  • Introduced modular JS structures and automation, enhancing maintainability.

NPM GULP Grunt JavaScript jQuery Handlebars CSS3 BEM HTML5 SASS
EnBW (Yello) ? Cologne
6 Monate
2016-01 - 2016-06

O2online portal

Senior UI Frontend Developer Scrum JADE SASS ...
Senior UI Frontend Developer

  • Developed multiple O2online portal modules, ensuring user-friendly cohesive experience.
  • Enhanced release quality with 99% bug-free launches via agile collaboration.

WEB STORM
Scrum JADE SASS NODE.JS jQuery
Telefónica Germany GmbH & Co. OHG
Munich, Germany
4 Monate
2015-09 - 2015-12

UI Design & Developement

UI Design & Developer HTML5 CSS3 jQuery ...
UI Design & Developer

  • Led UI rebrand for Uniper online energy-purchasing platform, aligning branding & boosting usability.
  • Reduced customer support requests by 15% through improved workflows.

IntelliJ Scrum
HTML5 CSS3 jQuery JavaScript Sass grunt compass Photoshop Scrum git bower Foundation
E.ON Energie Deutschland GmbH
Munich, Germany
2 Monate
2015-07 - 2015-08

E-learning

Web Designer / Digital Designer Photoshop wireframing after effects ...
Web Designer / Digital Designer
In this project I helped building the user interface, user experience and web design for an E learning platform where the sales department get in contact with the company new products.
adobe creative cloud
Photoshop wireframing after effects Axure
Huawei
7 Monate
2014-12 - 2015-06

Software design and development

Frontend Developer
Frontend Developer
  • Software design and development (incl. testing) for the ShareXell Software Suite
  • Global Job Mapping (T2)
Binder Consulting GmbH
Munich, Germany
6 Monate
2014-10 - 2015-03

Siemens Human resources

Frontend developer Scrum bootstrap HTML5 ...
Frontend developer

In this project I was responsible for the implementation of the application frontend.

Working in close contact with the UI/UX designers I was receiving design and usability files to implement using frontend technologies for a full responsive software application.

IntelliJ Git
Scrum bootstrap HTML5 CSS3 Sass Photoshop jQuery JavaScript
Siemens AG
1 Jahr 1 Monat
2013-04 - 2014-04

Senior Frontend Developer

Wearable Technologies AG
Munich
8 Monate
2012-08 - 2013-03

Digital Designer

CDM Munich
Munich
4 Monate
2010-09 - 2010-12

Frontend Developer

Ciant
Prague
9 Monate
2009-11 - 2010-07

TV Graphics Operator

wTVisio
Dubai
4 Monate
2009-03 - 2009-06

User Interface Designer Frontend Developer

University of Coimbra
Coimbra
6 Monate
2008-10 - 2009-03

FX Assistant + Video Editor

Aved Producciones
Barcelona
6 Monate
2008-02 - 2008-07

3D Modeler + Animator

Pedro Nunes Institut
Coimbra

Aus- und Weiterbildung

Aus- und Weiterbildung

2004 - 2009

M.Sc. Visual Information Technologies

University of Coimbra


Key Focus:

Focus on image analysis, computer vision, and large-scale data processing.


Certification

Data Science and Big Data Analytics, MITx on edX:

  • Training in ML, big data frameworks, and distributed analytics

Kompetenzen

Kompetenzen

Top-Skills

CSS JavaScript ReactJS Graphical User Interface User Experience Designer User Experience Design User Interface Designer User Interface Design User Interface Entwicklung ReactJS Adobe Photoshop Adobe Illustrator Sass

Schwerpunkte

html

Produkte / Standards / Erfahrungen / Methoden

BEM
bower
compass
Foundation
Git
Grunt
GULP
Handlebars
HTML5
IntelliJ
NPM
REST
Scrum
webpack
webstorm

Profile

Senior Frontend Engineer with 14+ years of experience building high-performance, user-centric applications across AI, blockchain, and enterprise platforms. Proven track record leading product launches from concept to production, driving adoption and scalability. Combines technical depth in modern JavaScript frameworks with design and strategic vision to deliver secure, intuitive, and future-ready digital experiences.


Web3 & Blockchain

Collaborated with startups and hackathons on blockchain/AI solutions. Developed prototypes and production-ready applications for Bitcoin, Ethereum, and Dfinity Internet Computer. Specialized in LLM integration with decentralized systems.


Core Technologies

Next.js, React, Vue, Svelte, Angular, JavaScript, TypeScript, Python, Go, C++, CSS, SASS, Webpack, D3.js, Highcharts, Tableau, GraphQL, MySQL, PostgreSQL, AWS (EC2, S3, CloudFront), Docker, GitHub, CI/CD, Cypress, Jest, Mocha, Figma, Adobe Creative Suite, Web3/Blockchain, LLMs, Vector Databases.


Soft Skills

Proven team leadership with cross-functional collaboration. Strong communication for bridging technical/non-technical stakeholders. Problem-solver with proactive mindset in fast-paced environments.


Career Goals

Seeking a senior leadership role (Head of Product / CPO) to drive the development of secure, multilingual, and scalable AI-powered products. Focused on streamlining complex regulatory processes, enhancing operational efficiency, and enabling global adoption within large, innovation-driven enterprises.


Programmiersprachen

css
css3
D3.js
Foundation framework
Handlebars.js
Highcharts
html 5
JADE
JavaScript
jQuery
JSON
jsp
less
sass
Vue vue.js

Datenbanken

graphQL

Design / Entwicklung / Konstruktion

After Effects
Illustrator
inDesign
Miro
Photoshop
Premiere
Sketch

Managementerfahrung in Unternehmen

confluence
jira
Product Owner
Scrum
Project Management

Branchen

Branchen

  • Insurance
  • Energie
  • Telecommunications
  • Aviation
  • Television

Einsatzorte

Einsatzorte

remote (+200km)
möglich

Projekte

Projekte

3 Jahre 8 Monate
2022-01 - 2025-08

Design and Development of On-Chain AI Chat Platform

Senior Frontend Engineer
Senior Frontend Engineer
  • Led the design and development of the first on-chain AI chat platform, enabling 10k+ users with end-to-end encryption and immutable audit trails.

  • Optimized Svelte-based frontend, reducing latency by 35% for LLM-driven interactions.

  • Partnered with product/security teams to integrate privacy-preserving AI workflows, increasing enterprise adoption.

OnicAI
remote
1 Jahr 7 Monate
2020-06 - 2021-12

Pioneering Generative UI Prototypes and Advanced Data Visualizations

Research Engineer
Research Engineer
  • Pioneered generative UI prototypes, influencing blockchain frameworks later adopted in 3 products.
  • Developed advanced data analysis dashboards, delivering insights for decision-making
  • Conducted UX research, shaping product roadmaps with data-driven insights
Forward Research
remote
6 Monate
2018-10 - 2019-03

Architected data processing platform

Full Stack Engineer graphQL Handlebars.js npm ...
Full Stack Engineer

  • Architected data processing platform handling millions of records daily, improving analytics speed by 40%.
  • Developed ML-driven UI reducing manual effort by 30%.
  • Enhanced enterprise UI speed with Python & Apache Spark integration.

webstorm
graphQL Handlebars.js npm Git D3 JavaScript JavaScript jQuery JSON REST Sass npm webpack
Allianz SE
Munchen
1 Jahr 5 Monate
2017-05 - 2018-09

tech strategy, scaling infrastructure and ensuring platform resilience.

CTO
CTO
  • Directed tech strategy, scaling infrastructure and ensuring platform resilience.
  • Cut downtime by 40% with CI/CD practices and optimized hosting environments.
  • Reduced infrastructure costs by 20% via vendor partnerships.
on request
6 Monate
2017-12 - 2018-05

Implemented mobile app

Senior Frontend Developer html css jsp ...
Senior Frontend Developer

  • Implemented mobile app rebrand with optimized real-time flight workflows, reducing response time by 20%.
  • Boosted mobile performance scores by 25% through iterative testing & tuning.

webstorm
html css jsp sass less jquery javascript git confluence jira JSP
Lufthansa ? Cologne, Germany
10 Monate
2016-09 - 2017-06

UI Frontend Developement

Senior UI Frontend Developer NPM GULP Grunt ...
Senior UI Frontend Developer

  • Redesigned sign-up flow, boosting conversions by 18% and reducing abandonment by 25%.
  • Introduced modular JS structures and automation, enhancing maintainability.

NPM GULP Grunt JavaScript jQuery Handlebars CSS3 BEM HTML5 SASS
EnBW (Yello) ? Cologne
6 Monate
2016-01 - 2016-06

O2online portal

Senior UI Frontend Developer Scrum JADE SASS ...
Senior UI Frontend Developer

  • Developed multiple O2online portal modules, ensuring user-friendly cohesive experience.
  • Enhanced release quality with 99% bug-free launches via agile collaboration.

WEB STORM
Scrum JADE SASS NODE.JS jQuery
Telefónica Germany GmbH & Co. OHG
Munich, Germany
4 Monate
2015-09 - 2015-12

UI Design & Developement

UI Design & Developer HTML5 CSS3 jQuery ...
UI Design & Developer

  • Led UI rebrand for Uniper online energy-purchasing platform, aligning branding & boosting usability.
  • Reduced customer support requests by 15% through improved workflows.

IntelliJ Scrum
HTML5 CSS3 jQuery JavaScript Sass grunt compass Photoshop Scrum git bower Foundation
E.ON Energie Deutschland GmbH
Munich, Germany
2 Monate
2015-07 - 2015-08

E-learning

Web Designer / Digital Designer Photoshop wireframing after effects ...
Web Designer / Digital Designer
In this project I helped building the user interface, user experience and web design for an E learning platform where the sales department get in contact with the company new products.
adobe creative cloud
Photoshop wireframing after effects Axure
Huawei
7 Monate
2014-12 - 2015-06

Software design and development

Frontend Developer
Frontend Developer
  • Software design and development (incl. testing) for the ShareXell Software Suite
  • Global Job Mapping (T2)
Binder Consulting GmbH
Munich, Germany
6 Monate
2014-10 - 2015-03

Siemens Human resources

Frontend developer Scrum bootstrap HTML5 ...
Frontend developer

In this project I was responsible for the implementation of the application frontend.

Working in close contact with the UI/UX designers I was receiving design and usability files to implement using frontend technologies for a full responsive software application.

IntelliJ Git
Scrum bootstrap HTML5 CSS3 Sass Photoshop jQuery JavaScript
Siemens AG
1 Jahr 1 Monat
2013-04 - 2014-04

Senior Frontend Developer

Wearable Technologies AG
Munich
8 Monate
2012-08 - 2013-03

Digital Designer

CDM Munich
Munich
4 Monate
2010-09 - 2010-12

Frontend Developer

Ciant
Prague
9 Monate
2009-11 - 2010-07

TV Graphics Operator

wTVisio
Dubai
4 Monate
2009-03 - 2009-06

User Interface Designer Frontend Developer

University of Coimbra
Coimbra
6 Monate
2008-10 - 2009-03

FX Assistant + Video Editor

Aved Producciones
Barcelona
6 Monate
2008-02 - 2008-07

3D Modeler + Animator

Pedro Nunes Institut
Coimbra

Aus- und Weiterbildung

Aus- und Weiterbildung

2004 - 2009

M.Sc. Visual Information Technologies

University of Coimbra


Key Focus:

Focus on image analysis, computer vision, and large-scale data processing.


Certification

Data Science and Big Data Analytics, MITx on edX:

  • Training in ML, big data frameworks, and distributed analytics

Kompetenzen

Kompetenzen

Top-Skills

CSS JavaScript ReactJS Graphical User Interface User Experience Designer User Experience Design User Interface Designer User Interface Design User Interface Entwicklung ReactJS Adobe Photoshop Adobe Illustrator Sass

Schwerpunkte

html

Produkte / Standards / Erfahrungen / Methoden

BEM
bower
compass
Foundation
Git
Grunt
GULP
Handlebars
HTML5
IntelliJ
NPM
REST
Scrum
webpack
webstorm

Profile

Senior Frontend Engineer with 14+ years of experience building high-performance, user-centric applications across AI, blockchain, and enterprise platforms. Proven track record leading product launches from concept to production, driving adoption and scalability. Combines technical depth in modern JavaScript frameworks with design and strategic vision to deliver secure, intuitive, and future-ready digital experiences.


Web3 & Blockchain

Collaborated with startups and hackathons on blockchain/AI solutions. Developed prototypes and production-ready applications for Bitcoin, Ethereum, and Dfinity Internet Computer. Specialized in LLM integration with decentralized systems.


Core Technologies

Next.js, React, Vue, Svelte, Angular, JavaScript, TypeScript, Python, Go, C++, CSS, SASS, Webpack, D3.js, Highcharts, Tableau, GraphQL, MySQL, PostgreSQL, AWS (EC2, S3, CloudFront), Docker, GitHub, CI/CD, Cypress, Jest, Mocha, Figma, Adobe Creative Suite, Web3/Blockchain, LLMs, Vector Databases.


Soft Skills

Proven team leadership with cross-functional collaboration. Strong communication for bridging technical/non-technical stakeholders. Problem-solver with proactive mindset in fast-paced environments.


Career Goals

Seeking a senior leadership role (Head of Product / CPO) to drive the development of secure, multilingual, and scalable AI-powered products. Focused on streamlining complex regulatory processes, enhancing operational efficiency, and enabling global adoption within large, innovation-driven enterprises.


Programmiersprachen

css
css3
D3.js
Foundation framework
Handlebars.js
Highcharts
html 5
JADE
JavaScript
jQuery
JSON
jsp
less
sass
Vue vue.js

Datenbanken

graphQL

Design / Entwicklung / Konstruktion

After Effects
Illustrator
inDesign
Miro
Photoshop
Premiere
Sketch

Managementerfahrung in Unternehmen

confluence
jira
Product Owner
Scrum
Project Management

Branchen

Branchen

  • Insurance
  • Energie
  • Telecommunications
  • Aviation
  • Television

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