Julio Marquez, Full-stack Developer in Buenos Aires, Argentina
Julio Marquez

Full-stack Developer in Buenos Aires, Argentina

Member since August 16, 2019
Julio has been a passionate full-stack developer for eleven years. He's architected complex web apps, led teams, and spoken at conferences in his field. Julio loves developing open-source projects and has +2,600 GitHub stars (JavaScript). He enjoys freelancing because it allows him to bring his expertise to new clients, discover challenging projects, and meet new people in the industry. Julio thrives in distributed teams and always emphasizes commitment, quality, and clear communication.
Julio is now available for hire




Buenos Aires, Argentina



Preferred Environment

GitHub, Git, MacOS, Ubuntu, GitLab, VS Code

The most amazing...

...thing I've built is Mapset, an innovative online tool for managing screens in different mainframe coding languages, 15x faster than any other tool available.


  • Co-founder | Full-stack Developer

    2015 - 2019
    • Co-founded a web development agency with the primary focus of standing out from the crowd by executing high-performance websites and mobile apps combining an eye toward transparency, inspection, and adaptation.
    • Contributed to bringing together an extraordinary experience by leveraging knowledge and ideas to build processes around quality and passion while working with exceptional people.
    • Executed, as a team, more than 42 projects including dynamic web and mobile apps, eCommerce sites, and corporative sites.
    • Drew upon a combination of a strong passion and continuous innovation and recognized that we can always be better to create products and open source projects to improve the web developer community.
    • Grew from two to 14 employees in eleven months and landed contracts with small and large companies.
    Technologies: Jest, Firebase, Vuex, TypeScript, AWS S3, GitHub, React, NativeScript, HTML, Pandas, Express.js, Django ORM, NPM, Sass, Django, REST APIs, Git, Python, Node.js, CSS, JavaScript, Serverless, Open Source, Vue.js, Nuxt.js, Bootstrap, jQuery, Back-end, HTML5, Front-end, Full-stack, Next.js, CSS3, PHP
  • Full-stack Developer

    2008 - 2016
    • Created a front-end admin template that earned +4.7 stars (out of 5) on Themeforest; it was fully responsive and cross-browser with Bootstrap and jQuery. Included easy-to-use components and a huge collection of plugins.
    • Built more than 20 high-performance websites, including dynamic web applications, eCommerce sites, and corporative sites.
    • Developed the initial layouts and built the front ends with HTML, CSS, JavaScript, jQuery, Ajax, and Angular/React.
    • Developed a back end using PHP, Python, MySQL, and PostgreSQL.
    • Integrated various third-party APIs including Google Map APIs, Google Analytics, Facebook APIs, and more.
    Technologies: Jest, Vuex, TypeScript, GitHub, React, HTML, Pandas, Express.js, Django ORM, NPM, Sass, Django, REST APIs, Git, Python, Node.js, CSS, JavaScript, Serverless, Open Source, Vue.js, Nuxt.js, Bootstrap, jQuery, Back-end, HTML5, Front-end, Full-stack, Angular, CSS3, PHP
  • Scientific Programmer

    2014 - 2015
    Geochemical Research and Engineering, Inc.
    • Worked on a research team of computational expertise to solve problems in the areas of reservoir simulation and fluid/gas injection.
    • Helped to create a unique-and-innovative product in the oil industry that perform complex computational simulation for aqueous speciation and mineral precipitation, based on the extensive and patented multi-year research of the company's founder.
    • Worked in a high-performance team focused on computer simulations to solve the most outstanding and difficult engineering calculations and computing processes in the oil industry.
    Technologies: REST APIs, Git, Python, Back-end, C#, MATLAB
  • Research Assistant

    2010 - 2015
    Satellite Geodesy and Seismotectonics Laboratory
    • Researched and developed computational simulations in the area of seismotectonic.
    • Planned, executed, processed, and analyzed georeferenced data from GPS measurements.
    • Adjusted geodetic control networks using satellite techniques and computational models and analysis.
    • Publish multi-year research findings in the Geophysical Journal International, a scientific journal published by Oxford University Press.
    Technologies: Pandas, Jupyter, REST APIs, Git, Python, JavaScript, Back-end, CSS3


  • Statusfy | A Marvelous Open-source Status Page system

    Statusfy is a status-page system that's easy to use and deploy to a variety of hosting services. The goal is to lower costs and complexity by providing a more straightforward and versatile open-source alternative.

    It was designed to generate a system that works as a progressive web application with the JAMstack architecture in mind and fast static generation. With these approaches, I wanted the users to enjoy a status-page system that gives better performance, higher security, cheaper hosting, and better user experience.

    I'm the author of this tool. I created the original project architecture, the back end, front-end code, and the visual identity, as well as an easy to use CLI (command-line interface) that improves the interaction and the building process of the system.

  • Mapset

    A new, innovative, and dynamic tool designed for managing screens in different mainframe coding languages. Mapset makes designing the mainframe screens commonly used in the banking industry less painful. Mapset became 15x faster than conventional methods or any other tool available.

    It's a cloud-based, inexpensive, very easy to use, and users don't need to be experts in the industry.

    I created the project architecture as well as the back-end code and led the front-end development while constantly communicating with the mainframe engineers who were experts in the banking and insurance industry. We discovered that the core of the product had to be a web application with a dynamic interface using the power of modern web browsers for the main tasks of the process.

    Besides, the serverless execution for the file conversion tasks was the best choice for reducing the overhead of servers: on-demand implementation, parallelism, and lower costs.

    Everything about the project was tested and documented to ensure the security and stability of the management of customer information.

  • Nuxt Optimized Images

    I created a Nuxt.js module to automatically optimizes images (JPEG, PNG, SVG, WebP, and GIF).

    Module Features:
    • Reduce image sizes by up to 60%.
    • Improve loading speed by providing progressive images and converting JPEG/PNG images to WebP on the fly for an even smaller size.
    • Resize images or generate low-quality image placeholders (LQIP) and extract the dominant colors of it.
    • Content hash to the file name so images can get cached on the CDN level and in the browser for a long time.
    • Inline small images to save HTTP requests and additional roundtrips.

  • The North Andes and the Caribbean and South American Plate Interaction

    When I was at college, I worked as a research assistant in the Satellite Geodesy and Seismotectonics Laboratory of the Simon Bolivar University (Caracas, Venezuela). We worked for four years in a very interesting project: finding the interaction of the North Andes plate with the Caribbean and South American plates in northwestern South America from GPS geodesy and seismic data.

    The work done on this project taught me many things: statistics, data analysis, interpretation of third-party research in addition to the importance of teamwork, great communication, and the commitment to your boss/supervisor and to the community to whom you're trying to give a scientific outcome.

    This research was carefully executed and went through a rigorous review process to be published in the Geophysical Journal International, a scientific journal published by Oxford University Press on behalf of the Royal Astronomical Society and the Deutsche Geophysikalische Gesellschaft.


  • Languages

    HTML5, HTML, JavaScript, Python, CSS3, Sass, CSS, TypeScript, GraphQL, PHP, C#
  • Frameworks

    Nuxt.js, Bootstrap, Django, Next.js, Tailwind CSS, Express.js, Jest, Vuetify.js, NativeScript, Flask, Redux, Angular
  • Libraries/APIs

    Vue.js 2, jQuery, Vue.js, Node.js, React, Pandas, REST APIs, Django ORM, Vuex, Matplotlib, NumPy, SciPy, OpenCV
  • Paradigms

    Clean Code, Testing, REST, Unit Testing, Test-driven Development (TDD), Serverless Architecture
  • Tools

    Pytest, Jupyter, Git, NPM, Gulp.js, GitHub, Sketch, VS Code, GitLab, MATLAB
  • Platforms

    Firebase, Docker, Amazon Web Services (AWS), Ubuntu, MacOS
  • Storage

    AWS S3, MongoDB, PostgreSQL, MySQL
  • Other

    Team Leadership, Teamwork, Open Source, GPS, Serverless, Georeferencing, Front-end, ESLint, Full-stack, Back-end, Code Architecture, Scientific Computing, University Teaching, Research, Challenge-based Learning, Team Building, Geophysics, Applied Research, English-Spanish Translation, Material Design, AWS, PWA, Progressive Web Applications (PWA), eCommerce, eCommerce Platforms
  • Industry Expertise

    Project Management


  • Bachelor's degree in Geophysical Engineering
    2006 - 2014
    Simon Bolivar University - Caracas, Venezuela


  • Latin America Representative
    MARCH 2014 - PRESENT
    American Association of Petroleum Geologists
  • Student Chapter Excellence Award
    Society of Exploration Geophysicists
  • Leadership Symposium Travel Grant Award
    Chevron and the Society of Exploration Geophysicists

To view more profiles

Join Toptal
Share it with others