Guillaume Ducret, Software Developer in Challes-les-Eaux, France
Guillaume Ducret

Software Developer in Challes-les-Eaux, France

Member since April 17, 2013
Guillaume is an independent consultant with ten years of experience working with small and large companies globally, focusing on Node.js and JavaScript architecture and development. As a technical lead, he facilitates the adoption of agile methodologies like Scrum.
Guillaume is now available for hire


  • Freelance
    Heroku, Redis, MongoDB, React, Node.js, Android, Flutter
  • UpliftNow
    React, Cloud Firestore, Flutter, Electron, Stripe, Agora, TypeScript
  • Performance Immo
    Gulp, Webpack, Redux, React



Challes-les-Eaux, France



Preferred Environment

Git, MacOS, VS Code

The most amazing... I've built is a call center application used by 500 agents which processes over 20,000 calls per day.


  • Software Architect | Full-stack Developer

    2015 - PRESENT
    • Developed a flutter package to display map tiles (Sterna—moving map for Flutter).
    • Created a dart package to sync data from a remote data source. Incremental sync is supported using a Git Repo as a data source (Hive-mirror, one-way sync for HiveDB).
    • Developed a react back end to generate PDFs (React-PDF kit, library to build PDFs using the React API).
    • Worked on both an Android application and an isomorphic web app, Livepeak—a live tracking app for outdoor enthusiasts.
    • Developed an Android application to monitor and control a life support device through a Bluetooth connection.
    Technologies: Heroku, Redis, MongoDB, React, Node.js, Android, Flutter
  • Lead Developer

    2019 - 2021
    • Helped the company to grow from the prototype stage to seed funding.
    • Developed a responsive web application from the ground up.
    • Formalized the development process and onboarded the first employees.
    • Developed a mobile app featuring chat and voice/video calls with Flutter.
    Technologies: React, Cloud Firestore, Flutter, Electron, Stripe, Agora, TypeScript
  • Lead Front-end Developer

    2015 - 2018
    Performance Immo
    • Developed a web app front-end from scratch with React.
    • Developed react-pdf, a React back-end to build PDF documents easily with the React API.
    Technologies: Gulp, Webpack, Redux, React
  • Front-end Developer

    2017 - 2017
    • Developed the front-end for a React Native app.
    Technologies: React Native
  • Lead Front-end Developer

    2015 - 2015
    Performance Consumer Groupe
    • Refactored an AngularJS application.
    • Managed two remote developers, defined coding guidelines, and approved pull requests.
    • Provided advice on the implementation of Scrum within the company.
    Technologies: Grunt, Bootstrap, Less, CSS3, HTML, AngularJS
  • Software Consultant

    2014 - 2014
    The Stack Holder Company
    • Defined the architecture and developed a scalable news monitoring application based on web crawling, content analysis, and entity extraction.
    • Set up a deployment process on AWS, using Git push hooks.
    • Defined and prioritized the product backlog with the product owner.
    • Hired and managed remote freelancers to develop web scrapers.
    Technologies: Amazon Web Services (AWS), AWS, MySQL, Elasticsearch, NLTK, Scrapy, Django, Python
  • Lead Front-end Developer

    2013 - 2014
    • Refactored an AngularJS application.
    • Made the application responsive to work on phones, tablets, and desktops.
    • Implemented a back-office application in AngularJS from the ground up.
    • Worked closely with the product owner to define and prioritize the backlog.
    Technologies: Grunt, Karma, Jasmine, Bootstrap, Less, Sass, CSS3, HTML5, AngularJS, CoffeeScript
  • Full-stack Developer

    2012 - 2013
    • Built a social platform inspired by Pinterest, with a focus on user collaboration.
    • Used PhantomJS to improve the SEO of the single-page application.
    • Integrated Google Maps to display location-based search results.
    Technologies: Backbone.js, Heroku, Solr, Redis, MongoDB, Node.js, JavaScript
  • Technical Lead

    2010 - 2012
    • Developed a content exchange platform with social features for this Singapore-based startup.
    • Improved productivity and managed business expectations by implementing Scrum methodology within the organization.
    • Managed three cross-functional teams of fifteen individuals, which included such tasks as running daily standup meetings, performing code reviews, and ensuring quality of delivery.
    • Designed and implemented key framework components, including a persistence layer on top of Cassandra and an event infrastructure.
    Technologies: Amazon Web Services (AWS), Linux, AWS, Apache JMeter, jQuery, RequireJS, Jetty, Spring, Jackson, Jersey, REST, HornetQ, Solr, Cassandra, JavaScript, Java
  • Software Architect

    2008 - 2010
    • Worked as a software architect on a new call center application used by 500 agents and processing over 20,000 phone calls per day for a French pension fund.
    • Wrote technical specifications with UML.
    • Provided expertise on OSGI.
    • Built a technical infrastructure on top of OSGI by integrating frameworks to support clustering, hot deployment, client-server communication, and functional scalability.
    • Deployed a build management infrastructure using Maven2 and Hudson.
    Technologies: Linux, Shell Scripting, ClearCase, Hudson, Maven, AVAYA, JTAPI, JMX, RMI, Eclipse RCP, Hibernate, JBoss Cache, Apache MINA, Spring, OSGi, Java
  • Software Engineer

    2007 - 2008
    • Designed and developed a messaging web application to facilitate the communication between employees located in two different offices for a tax collection agency in France.
    • Provided expertise on Hibernate and Quartz to solve design issues on a clustered web app.
    • Implemented Web Services using Axis2.
    • Successfully overcame a scalability issue by setting up a load test infrastructure and optimizing SQL statements.
    Technologies: Eclipse, CVS, Continuum, Maven, Apache JMeter, PostgreSQL, Apache Axis 2, Hibernate, Quartz, Apache Struts, jQuery, Ajax, CSS, JSP, Apache Tomcat, Jakarta EE, JavaScript, Java
  • Software Engineer

    2006 - 2007
    • Designed and developed automated non-regression test tools within the quality assurance department of a French travel software company.
    • Developed a Java layer on top of the C++ central system communication API with JNI.
    • Increased process efficiency by developing a tool to test back-end availability.
    Technologies: Eclipse, ClearCase, Microsoft SQL Server, Ant, XSLT, jQuery, JavaScript, JSP, JNI, WebLogic, Jakarta EE, Java
  • Software Engineer

    2004 - 2006
    • Developed and tested a business process management web app.
    • Wrote functional test plans and signed off releases.
    • Performed load testing and tuned application server accordingly.
    • Tested database compatibility.
    • Provided second-level support for customers.
    • Wrote how-to and code snippets for developer users.
    Technologies: OpenStack, Eclipse, Visual SourceSafe, Oracle, MySQL, BPM, JUnit, JBoss, Jakarta EE, Java


  • Flight Display

    A collection of EFIS (Electronic flight instrument system) components implemented with Flutter. This is a personal project to evaluate Flutter.

  • Livepeak

    Live tracking for your outdoor activities. Livepeak uses your phone's GPS to share your location in real time.

    This is a personal project, of which I performed 100% of the designing and programming.

  • AyStack

    Collaborative aggregation platform. It's always been challenging to discover and follow great content on the web that matches your interest. AyStack relies on a community of users to make it easier.

    This is a personal project, of which I performed 100% of the designing and programming.


  • Languages

    JavaScript, Java, Kotlin, CSS, XSLT, HTML, CSS3, Less, Python, CoffeeScript, HTML5, Sass, TypeScript
  • Frameworks

    Redux, Spring, OSGi, Hibernate, Flutter, Jersey, JSP, Apache Struts, Apache Axis 2, Apache MINA, JNI, JUnit, AngularJS, Bootstrap, Django, Scrapy, Jasmine, React Native, Electron
  • Libraries/APIs

    Node.js, React, Java RMI, JTAPI, RequireJS, jQuery, Backbone.js, Jackson, Quartz, JMX, NLTK, Stripe
  • Tools

    Maven, Eclipse IDE, Apache JMeter, Git, Eclipse RCP, Solr, IntelliJ, Jetty, Apache Tomcat, Continuum, CVS, Hudson, ClearCase, Visual SourceSafe, Grunt, Karma, Webpack, Gulp, VS Code, Agora
  • Paradigms

    Scrum, Test-driven Development (TDD), REST
  • Platforms

    Google App Engine, Android, Amazon Web Services (AWS), Heroku, MacOS, Jakarta EE, Eclipse, JBoss, Oracle, OpenStack, Linux
  • Other

    Architecture, HornetQ, AWS, Ajax, RMI, AVAYA, Shell Scripting, WebLogic, Ant, BPM, OpenSTA
  • Storage

    Elasticsearch, MongoDB, Cassandra, PostgreSQL, JBoss Cache, Microsoft SQL Server, MySQL, Redis, CouchDB, Cloud Firestore


  • SCRUM Master Degree in Agile Methodologies
    2012 - 2012
    ODD-E - Singapore
  • Master's Degree in General Education, Software architecture, and Integration of Systems Specialty
    1999 - 2004
    EPF - Paris, France

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