Diego Alisson Fernandes de Mendonca, Developer in Dublin, Ireland
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Diego Alisson Fernandes de Mendonca

Verified Expert  in Engineering

Software Developer

Dublin, Ireland
Toptal Member Since
October 15, 2021

Diego is a senior software engineer with over 15 years in software development across various industries, mostly following Agile principles, with a focus on UI working on different frameworks, browsers, and environments he's vast knowledge brings extra value to the project. Diego is a skilled hands-on developer who understands the client's expectations and knows how to translate the requirements into well-designed and scalable solutions.


JavaScript, React, Node.js, NoSQL, Accessibility, AngularJS, TestCafe, Karma...
JavaScript, HTML, CSS, React, TypeScript, Jest, Redux Thunk
React Native, Docker, Swagger, Redux, Redux-Saga, Android, iOS, GitHub, Jenkins...




Preferred Environment

MacOS, Linux, Slack, Visual Studio Code (VS Code), Jira, GitHub, Bitbucket

The most amazing...

...system I've developed is a web platform resulting in an outstanding development experience in a large-scale company in the insurance industry.

Work Experience

Software Engineer Manager

2021 - PRESENT
  • Developed with the team a design system and web platform (SAAS) for other companies in the insurance industry, heavily metadata-driven applications using React as bases for components rendering.
  • Used Jira and Aha! to manage the features, epics, stories, and triage meetings to address bugs and release priorities.
  • Developed an upgradable standard for the platform, moving the customers to the latest and greatest scenario with the minimum effort and downtime possible.
Technologies: JavaScript, React, Node.js, NoSQL, Accessibility, AngularJS, TestCafe, Karma, Webpack, Amazon DynamoDB, Express.js, Amazon Web Services (AWS), NPM, Artifactory, TeamCity, Artificial Intelligence (AI)

Software Engineer | Team Leader

2020 - 2021
  • Drove the development of the sustainable initiatives at Mastercard, the Priceless Planet Coalition.
  • Used Scrum as Agile methodology, tracked stories using Rally the scope of deliverables driven by priorities. I collected from the vice president of the initiative and distributed the work with the team, contributing coding.
  • Implemented The Planting Trees initiative which receives donations worldwide to plant new trees in the areas predefined by Mastercard.
Technologies: JavaScript, HTML, CSS, React, TypeScript, Jest, Redux Thunk

Architect UI Engineer

2019 - 2021
  • Maintained for a while the existing implementation of the platform and upgraded to the latest Angular versions.
  • Started the platform from scratch using React and React Native and reduced the page loading time from 15 seconds to one second on average.
  • Designed and implemented the multi-language (I18n) and themeable interfaces using CSS variables.
  • Applied high standards on quality of code delivered with the unit, code coverage above 70%, and E2E tests.
  • Delivered applications on Android and iOS platforms and the deliverables on web applications in an automated mechanism.
Technologies: React Native, Docker, Swagger, Redux, Redux-Saga, Android, iOS, GitHub, Jenkins, Jest, React Testing Library, Xcode

Staff Software Engineer | UI

2016 - 2020
  • Developed and delivered throughout the company and customers the component libraries that aligned the identity of the company and software development.
  • Implemented best practices and support on data-driven application and introduced accessibility compliance Level AA.
  • Supported and migrated the front-end frameworks to the latest cutting-edge technologies with training and workshops.
Technologies: AngularJS, React, TestCafe, Karma, Mocha, Node.js, Webpack, Grunt, Express.js, AWS Lambda, Amazon DynamoDB

Senior Software Engineer

2013 - 2016
Avenue Code
  • Learned Ruby on Rails and used the technology to implement the internal application.
  • Contributed my UI experience to define the application and worked on internal projects getting in touch with different technologies and guiding the UI/UX.
  • Oversaw the internal projects being consumed and managed internally, improving the HR's project requirements and time allocation.
Technologies: JavaScript, HTML, Cucumber, Backbone.js, Backbone.Marionette, RequireJS, Handlebars, Vagrant, Git, Grunt, jQuery, Java, Apache Maven

Senior Software Engineer

2013 - 2016
  • Maintained and evolved an eCommerce website with more than 30 million page views per day while working in a multi-country agile-driven team.
  • Followed Agile principles using the acceptance test-driven development philosophy. To support our workflow, we used unit and integration testing and code quality analysis tools.
  • Improved the user experience, SEO for searching engines, and payment integration.
  • Bootstrapped the prototype for the tablet version of the website, resulting in a whole new development workstream at Bloomingdale's and Macy's.
  • Worked on the lab team creating experiments to improve the user experience collecting data from A/B testing in shopping conversion.
Technologies: Node.js, Backbone.js, Backbone.Marionette, Handlebars, Jenkins, Mocha, CSS, HTML, Java, JavaScript, Jasmine, Cucumber, Vagrant, Grunt, RequireJS, YUI, Apache Tiles, Foundation CSS, Apache Maven, Test-driven Development (TDD)

SoMee Social

Developed web and React Native applications for social media, using React on both web and mobile. Implemented high-standard requirements and features to support a11y, i18n, testing, and automation. I also worked on microservices developed in Node.js and PHP for the back end.
2005 - 2009

Bachelor's Degree in Internet of Things

UniBH - Belo Horizonte, Brazil


React, Node.js, Redux-Saga, Backbone.js, Backbone.Marionette, Handlebars, RequireJS, YUI, jQuery, React Testing Library


Git, GitHub, Confluence, TeamCity, Jenkins, Redux Thunk, Cucumber, Vagrant, Grunt, Apache Maven, Karma, Webpack, Slack, Jira, Bitbucket, Xcode, NPM, Artifactory, Mocha


JavaScript, HTML, CSS, Java, PHP, Swift, TypeScript


REST API Architecture, Web Architecture, Test-driven Development (TDD)


NoSQL, Redis, Amazon DynamoDB


React Native, Redux, Detox, Cypress, Jest, Android SDK, Jasmine, Apache Tiles, Foundation CSS, AngularJS, TestCafe, Express.js, Swagger


MacOS, Linux, Amazon Web Services (AWS), Docker, Android, iOS, AWS Lambda, Visual Studio Code (VS Code)


Web Development, Accessibility, Artificial Intelligence (AI), Web Project Management, RTL

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